Sarit's Blog

Configuring IPv6 on pfSense Behind an AT&T BGW210 Gateway

noreply@blogger.com (Sarit) — Mon, 10 Nov 2025 00:02:00 +0000

How I Configured IPv6 on My Home Network Using pfSense and an AT&T BGW210 Gateway

Introduction

IPv6 adoption has been steadily growing, and configuring it correctly in a home network can improve gaming, streaming, and overall connectivity. In this post, I’ll walk through how I set up IPv6 on a pfSense router behind an AT&T BGW210 gateway. This setup provides fully functional IPv6 for all devices on the LAN while keeping the network secure.

Network Overview

ISP: AT&T U-verse
Gateway/Modem: AT&T BGW210 (model 700 series)
Router: pfSense 2.7.2-RELEASE
LAN Devices: Mix of macOS, Windows, and smart home devices
IPv6 Goal: Enable full IPv6 connectivity for LAN devices, including gaming and VoIP, with minimal configuration and proper inbound/outbound traffic control.

Key IPv6 Challenges with BGW210

The BGW210 is a typical AT&T gateway, which presents a few unique challenges:

It provides only a single /64 IPv6 subnet to downstream routers in IP Passthrough mode.
It does not support full prefix delegation to multiple LAN subnets.
The WAN interface of pfSense receives a single IPv6 address, and the delegated prefix is “virtual” — pfSense cannot track it automatically.

As a result, a standard Track Interface setup won’t work. Instead, we assign a static IPv6 to the pfSense LAN interface and use Router Advertisements (RA) to let clients auto-configure their own addresses.

pfSense IPv6 Configuration

WAN Interface

IPv6 Configuration Type: DHCP6
Do Not Wait for RA: Checked (required for AT&T)
Prefix Delegation Size: 60 (ignored by AT&T, still recommended)
Send IPv6 Prefix Hint: Checked
IPv4 as Parent: Checked
Firewall Consideration: Allow ICMPv6 inbound (all types recommended for proper connectivity)

LAN Interface

IPv6 Configuration Type: Static IPv6
IPv6 Address: 2600:xxxx:xxxx::1/64 (redacted example)
Router Advertisements (RA) Mode: Assisted
DNS via RA: Enabled, mirrored from DHCPv6

Notes:

Prefix length /64 is required.
Clients receive addresses automatically via SLAAC.
Temporary privacy addresses are generated automatically by macOS, Windows, etc.

Firewall Rules

LAN (Outbound)

Rule Type: Pass
Address Family: IPv4 + IPv6 (combined)
Protocol: Any
Source: LAN net
Destination: Any

WAN (Inbound)

Allow ICMPv6: Protocol ICMP, Type: any (ensures RA, NDP, and PMTU work)
Optional: Specific TCP/UDP ports for gaming or VoIP

NAT is not required for IPv6; firewall rules handle inbound/outbound traffic.

Client Verification (macOS Example)

Open Terminal and run:


ifconfig en0 | grep inet6

Expected output:


inet6 2600:xxxx:xxxx::abcd prefixlen 64 autoconf
inet6 2600:xxxx:xxxx::ef12 prefixlen 64 autoconf temporary
inet6 fe80::xxxx prefixlen 64 scopeid 0xf

Global IPv6 addresses (2600:…) are assigned via RA/SLAAC.
Temporary addresses are for privacy.
fe80:: is the link-local address.

Test connectivity:


ping6 google.com

Additional Settings

I found out also through this page that the AT&T gateway has limited states so we should limit the number of states on pfSense to not go over it.

Set the pfSense state limit in Advanced -> Firewall & NAT -> Firewall Maximum States

to 7500 as suggested

Why This Setup Works

All LAN devices automatically receive a global IPv6 address from the pfSense LAN /64.
ICMPv6 rules ensure proper Neighbor Discovery, Path MTU, and RA messages.
Games and VoIP apps that support IPv6 can connect directly without NAT.
Minimal configuration is required — no manual IP assignment on each device.

Conclusion

Even with AT&T’s BGW210 gateway, which only provides a single /64 and limited prefix delegation, it is possible to configure a fully functional IPv6 LAN using pfSense. The key is to assign a static IPv6 on the LAN interface, enable RA in Assisted mode, and allow ICMPv6 traffic on the WAN.

This setup ensures modern devices get the benefits of IPv6 automatically while keeping your network secure and accessible for gaming and VoIP.

How to download photos from an Amazon Photos Album

noreply@blogger.com (Sarit) — Mon, 11 Mar 2024 00:09:00 +0000

Option 1: To download all the photos in the album

Click on the vertical 3 dots icon on the top right. A menu should open allowing you to download all of them.

Option 2: To download a single photo

Open the photo you want to download so you can see the big version of it. Then click on the horizontal 3 dots icon on the top right to expand the menu with the download option.

Getting my old Logitech Quickcam Pro 4000 to work on Octoprint

noreply@blogger.com (Sarit) — Sun, 20 Nov 2022 00:56:00 +0000

The library that Octoprint uses to connect to a webcam and stream images to the octoprint window is called mjpg-streamer. It works for many webcams, but of course not my trusty Logitech Quickcam Pro 4000. Upon further investigation it turns out my camera only supports the Y12 format but that library can support just the YUV version of that format (there's even a pull request to add support for it). Luckily someone has made their own service called PICS which can read that format and it works pretty well. I forked the project and added some helpful code to allow you to automatically run PICS at boot. Clone the repo, follow the steps to build and run in the Readme, then scroll to the end and follow the steps to "Creating a service to start PICS on boot". This creates a stream that can be viewed at http://octopi.local:8080/dev/video0 which is the URL you can use in the Octoprint WebCam config.

Connecting the Raspberry Pi to the Robin Nano via GPIO pins

noreply@blogger.com (Sarit) — Mon, 31 Oct 2022 09:13:00 +0000

Since the Robin Nano board is mounted such that the USB port is only accessible outside the printer, I had to snake the USB cable out through one of the holes and around the printer to reach the port. For a clean installation, I need a way to let the Raspberry Pi connect to the nano using the GPIO pins.

USB port can only be reached from the outside

Currently, however, most of the easily accessible pins are already taken on my board as part of enabling SPI communication on the TMC2209 drivers.

Most easy to access pins are used

So I went hunting for pins that I could use and it turns out most of the pins on the TF connector can at least be used for SPI freeing up the pins on the WIFI connector that are most commonly used for RPI communication. So the plan now is to rewire the 5 SPI wires into a single 9-pin JST-XH connector and then use the WIFI pins for RPI.

Establishing Common Grounds

Before we can hookup I/O pins between separate devices, we need to ensure that they all have a common I/O ground. This is different from grounding the printer (which you should do as well). What I mean is that the negative terminal on the DC side of all the power supplies should be connected together. This ensures that the 24v line from the 24v PSU is actually 24 volts above any of the DC grounds and the 5v line from the 5v PSU is actually 5 volts above the same ground lines. When I had the USB cable connected, there was a ground wire that joined the PSU's together. Although, I could have added a ground wire as part of the wires connecting the RPI with the Robin Nano, its usually better practice to join the PSUs directly to minimize any current going over the ground GPIO pins.

In the end, I connected the GPIO pin14/15 (which are pins for a serial port) on the RPi4 to pins PA10/PA9 on the Robin Nano, respectively. Note that you must cross the wires so that the TX from one boards goes to the RX pin on the other board and vice versa.

Klipper/RPi Configuration

Next, I had to build a new klipper firmware so that it would know to listen on the correct pins.

I ran through make menuconfig as per the klipper installation instructions being sure to use the same settings described in the top of my printer.cfg regarding booloader size, startup pins, etc. The difference this time, is I picked the serial connection to match the new pins we're using.

After this I:

saved the config
ran "make" to build the image
used the mks script to convert the image to one compatible with robin nano
used Filezilla to get the file onto my computer
copied image to sd card
booted robin nano with sd card (the image file will get renamed with a *.CUR extension)

Next I had to configure printer.cfg to use the correct serial port. Klipper docs don't document this correctly. They assume you are using USB. Instead of using their command, use "ls /dev/serial*" but at this point the serial ports are not configured correctly. This doc proved helpful: https://docs.google.com/document/d/1kFasg5H_YDpIwc0PZpKph6RTX4BPROkNgTojQ0RWks8/edit

Basically, I first need to configure RPi to disable bluetooth, enable serial ports, disable shell on serial ports. This was done with a combination of editing /boot/config.txt and running raspi-config.

After all was set and done, I had 2 serial interfaces /dev/serial0 and /dev/serial1 with serial1 mapped to /dev/ttyS0 which is the one that corresponds to the GPIO pin 14/15.

Finally, in printer.cfg under the [mcu] section, I set the "serial" to "/dev/ttyS0". Restarted everything and then it all worked.

Crashplan Scripts on QNAP

noreply@blogger.com (Sarit) — Wed, 17 Aug 2022 16:21:00 +0000

Looks like QNAP will delete/recreate many directories like /root when it reboots so you can't keep your crashplan scripts there. You can get around this by creating a shared directory. I made one called scripts which can be access by /share/scripts.

I put the update scripts there too so now I can ssh into the QNAP, cd to /share/scripts and run update_crashplan.sh.

Refuting the Chinese Room Argument

noreply@blogger.com (Sarit) — Mon, 27 Jun 2022 01:15:00 +0000

This post assumes you already know about the Chinese Room Argument developed by John Searle.

Before I refute it, let's begin with a simple explanation of what the experiment entails:

A person who understands Chinese writes down a message using Chinese characters and places it into the mail slot of a room. The person cannot observe anything about the room's contents including what is going on inside of it.
Inside the room is John Searle, he has buckets of Chinese symbols and a book that describes for each combination of Chinese symbols, English instructions on how to arrange the Chinese symbols in the buckets onto a piece of paper which he send back out through the same mail slot. Searle, himself has no understanding of Chinese, he blindly follows the instruction in the book.
The person outside the room, reads the message from Searle and because it's content and the fact that it is written in Chinese is then convinced that there must be a person who understands Chinese in the room.
Because Searle never understands Chinese, he is only performing syntactic symbol manipulation. There is no semantics going on. Without semantics there can be no strong AI.

Let me now write the steps of the thought experiment down so it's clear before I make changes to them:

Chinese speaker writes down message, places it in mail slot
Searle looks at message, thumbs through book to find matching page
Searle follows the instructions on the page to form a response
Searle places the response back through the mail slot
Chinese speaker reads Searle's message and concludes Searle understands Chinese

Now suppose we make a small alteration to the experiment, but in a way that you shall see is immaterial to the experiment itself.

Suppose that the room has a 2nd mail slot on the back wall that leads to a 2nd room. Just as the Chinese speaker cannot see into Searle's room, Searle cannot see into the 2nd room. Additionally, to the Chinese speaker, the original room and this room are identical (conceptually the original room is divided into 2 rooms internally).
The book that Searle uses is also different. It still contains all the same Chinese symbols except now, the place where there were English instructions is blank.
Searle however can now tear out that page from his book and place it into the 2nd mail slot and within a negligible amount of time, the page will be returned through the same slot with the previously missing English instructions. Assume these instructions match the instructions in the original experiment.

So now let's write these new steps down:

Chinese speaker writes down message, places it in mail slot
Searle looks at message, thumbs through book to find matching page

Searle tears out the page and places it into 2nd mail slot
The page is returned with the instructions on it
Searle puts the page back into his book

Searle follows the instructions on the page to form a response
Searle places the response back through the mail slot
Chinese speaker reads Searle's message and concludes Searle understands Chinese

As you can see, the additional steps we added are inconsequential to the experiment. Whether the page already had the instructions on it or whether Searle performs an extra step using purely syntactical operations to get that instruction, the result is the same. Searle still doesn't understand Chinese, so we must conclude there is no Chinese understanding going on and thus strong AI is false.

But wait! I haven't told you what was in the 2nd room

Inside the 2nd room was a person who understands both Chinese & English. He/she used their understanding of Chinese to formulate a response in Chinese, then used their understanding of English to create the necessary instructions for Searle to construct that response.

So what's the problem?

The Chinese room is an analog for a Turing Machine (aka digital computer). By having Searle in essence "be the computer", the idea is that if Searle never understands Chinese, then all computers for which he is an analog for would never understand Chinese either. The test requires that if Chinese understanding were to exist in the Chinese room, then it must be within Searle. Is that true though? Because, didn't we just show that understanding could definitively be in the Chinese room and entirely separate from Searle?

A test that fails to detect what it's meant to detect, shouldn't be used to infer anything.

Systems Reply?

Some may point to Searle's systems reply as a rebuttal. Namely that Searle could internalize the content of the book (with the instructions). However doing so results in the same conclusion that he made --> Searle doesn't understand Chinese and that's precisely the point. In this case, where we know Chinese understanding exists, we'd want Searle to then understand Chinese (not only that the same understanding of Chinese as the person in the 2nd room).

I don't believe the 2 experiments are truly identical, surely their difference is consequential

Okay, lets have the same person from the 2nd room go through the entire book filling out the instructions, then and only after doing all of them, he places the book in Searle's original room and leaves. The Chinese room starts off indistinguishably from the original. The room, book, people are all the same. The only difference being the author of the book. In the original it's a programmer, in the 2nd it's the person who understands Chinese and English.

[3D Printer Series] AC powered heated bed and safety

noreply@blogger.com (Sarit) — Mon, 31 Jan 2022 08:37:00 +0000

A normal 24v DC heated bed usually takes a while to come up to temp, especially if you want to print with higher temperature filament. Not only does it take a long time, but it also consumes a lot of the PSU power. That's why if you want to heat up your bed faster, you'll want an AC powered unit.

I purchased this:

Which perfectly fit my new cast aluminum plate and it's mounting holes. Since we can no longer use the Robin Nano controller board to feed this 120V AC and 750 watts is much more than my PSU can handle, I also got a 40amp solid state relay (SSR). You'll want an SSR so that the Robin Nano can still control the heater with a PWM signal. The SSR needs to support a control input of 24V DC and be able to switch 120V AC. For our needs a good quality 10A SSR would suffice but since I don't trust these off brand models I went with a 40A model for extra insurance.

DC to AC 40A SSR

Thermal Runaway

Even good SSRs can fail and the worst way for it to fail is if they fail with the circuit closed (i.e. permanently on) which would mean there's nothing stopping the AC power from flowing to the heater until it catches on fire.

First line of defence: Thermal Fuse

To prevent this, I added a thermal fuse in series with the wire for the heater power. If the temperature exceeds a certain level, the fuse should blow and the heater should get disconnected. To attach the thermal fuse, I used RTV silicone sealant, which seems to be the adhesive of choice for this task among the Voron crowd. Then to insulate the bottom, I added a self stick foil faced insulated pad used on automobiles. The adds another layer of insurance to keep the thermal fuse in contact with the heater pad.

Thermal Fuse

Insulated Pad

RTV Silicone Sealant

2nd Line of defense: Pi controlled relay

Relying just on the thermal fuse might be okay if you plan to continuously monitor your printer but I don't want to monitor my prints so closely. So for an added measure of safety, we want to make sure our heater bed remains disconnected at all times except when the bed is heating. A regular relay can do this for us if we connect the wires leading to the SSR through our relay using the relay's NO (normally open connection). This is nice because we have to actively supply power to the relay to keep the power flowing to the heated bed. The relay I used is the Elegoo 4 relay module. It's nice because the inputs can be isolated from the power used to energize the relay coils.

Elegoo 4 relay module

Why do we need to electrically isolate?

The logic/GPIO pins on the RPi operate at 3.3V but the coils on the relay work on 5V. To make this work we need to separate the relay's logic voltage from the relay's coil voltage. According to the documentation this can be done by removing one of the jumpers:

Remove the jumper to allow mixed voltages

Then you can wire up the module like so. (Note only the top pin under the jumper should be supplied with 5V)

Luckily, the RPi has some 3.3V pins close to some GPIO pins so I chose the first 3 pins since I knew I wanted to control 2 relays, but you can choose the ones that work for you.

I chose these pins (green), but you do you

For the 5V and ground connections, you can either use the same 5V PSU connections as the RPi or daisy chain it from the header pins (pins 4 & 6).

Configuration

In OctoPrint, I first used the GPIO Control plugin which is good if you want to manually control the relay. The thing to remember is that you need to configure the "Active" dropdown to "LOW" to indicate that activating the relay requires the GPIO pin to be connected to ground (0V). That's usually how these relays work. If you see the relay light come on when you command the pin to be "ON" then it's configured correctly. If the light doesn't come on then you might have a relay that's configured for active "HIGH". If the light works correctly, but the relay itself is opposite, then you've likely wired the output of the relay to the "NC" (normally closed) pin instead of the "NO" (normally open) pin which we want for passive safety. The "GPIO" number should match the label in the pic above.

Active should be set to "LOW" for most relay modules

Advanced Configuration

Using GPIO Control is relatively straight forward, but you'll have to remember to turn on your heatbed before every print and then turn it off after. I'd rather have Klipper do that for me automatically. Additionally, since Klipper has temperature safety checks, that will shutdown the printer when it detects a temperature abnormality, I want that to also shutdown the relay controlling the heat bed. But how can you get it to trigger a GPIO pin on the RPi? Answer: RPi microcontroller

You can add the RPi to Klipper as a secondary microcontroller (mcu) and use it's GPIO pins as if it was just another driver board. To do so, follow the instructions in the link above and in the end you should have added something similar to the following lines to the klipper printer.cfg:

[mcu pi]
serial: /tmp/klipper_host_mcu

In my case, I named the RPi mcu as "pi" but you can name it whatever you like, just remember it.

At this point your config doesn't do anything, it just establishes the RPi as something klipper can control. To have it turn on the heated bed when the bed is active we can use the [controller fan] configuration which essentially enables the configured pin when the specified heater is active. Just make sure we keep the speed at 1.0 (ie 100%) since we don't want to pulse the pin on/off. Luckily the default config is just that.

[controller_fan heater_relay]
pin: !pi:gpiochip0/gpio3
heater: heater_bed

Notice that we include a "!" in the pin configuration. That inverts the logic of the pin just like how we set active to "LOW" using GPIO Control. The rest of the pin configuration is explained in the klipper docs.

Now I just start my prints as normal and the heater bed relay turns on automatically, sweet!

[3D Printer Series] Understanding how to set z_offset on Klipper

noreply@blogger.com (Sarit) — Wed, 19 Jan 2022 07:28:00 +0000

Z-Offset is a general name for telling the printer how far the nozzle is from some reference point. The reference point can be either a z end stop or the probe position of a bed probe like a BLTouch. The confusing bit is what happens when you have both an end stop and a probe. In that case you'll want to use the end stop to move the z-axis to a fixed position and then rely on the bed probe only for bed leveling/compensation.

Klipper doesn't explain how the different options interact with each other making this process very confusing. Additionally, following their calibration guide will lead you down the wrong path if you are using a similar configuration as me. Here's how I do it and why:

Offset for z end stop/probe for bed mesh

We will essentially be using the z end stop as our absolute reference, but when we add bed mesh leveling there's an important config that makes our bed mesh work relative to the z end stop, and that is the key. You don't need to do PROBE_CALIBRATE as we never try to use the probed position for absolute positioning.

Use the [bed_screws] and [screws_tilt_adjust] configuration to define where the bed level screws are on the xy plane. While you're at it, create an OctoPrint macro/button to move the nozzle above the first screw, this will come handy later.
Next, tighten all the bed screws so the nozzle doesn't crash into the bed.
Use your macro to move the head above the first screw and home the z-axis.
Adjust the first bed screw so that the nozzle is about 1-2 mm above the bed.
Use the SCREWS_TILT_CALCULATE command to level the other 3 screws, repeat till you get it pretty close
ACCEPT when you are done
SAVE_CONFIG
Preheat the bed to your normal print temp
Run Z_ENDSTOP_CALIBRATE but use a feeler gauge to get a precise gap between the nozzle and bed, then subtract out the thickness of the gauge. We do this instead of the paper test because the bed is now heated and the gauge is an accurate thickness. This is your effective z offset. If you get an out of bounds error, you will need to configure the min z position with a small negative number.
ACCEPT when you are done
SAVE_CONFIG
Add a [bed_mesh] config, but be sure to include a relative_reference_index that corresponds to the first screw position.
Run BED_MESH_CALIBRATE
SAVE_CONFIG, if you look at your printer.cfg, see if you can find the bed mesh values at the end. The value for the relative_reference_index should be 0 if you've configured it correctly.
Do a single layer test print. I use calipers measure the thickness of the layer. I'll then manually change the [stepper_z] position_endstop to tweak the first layer until I get a thickness that matches the thickness specified in the gcode.

[3D Printer Series] Updating Octoprint/Klipper for Python 3

noreply@blogger.com (Sarit) — Tue, 18 Jan 2022 08:43:00 +0000

After upgrading/resurrecting my Sapphire Plus with a new cast aluminum build plate, 750 AC silicone bed heater, SSR, relay board, magnetic textured PEI build surface, I was prompted to update OctoPrint since it was going to stop supporting Python 3. Unfortunately, if you use OctoPrint w/ Klipper the update steps are a lot more involved than explained.

After you update your Raspberry Pi, you basically have to reinstall Klipper as well and installing Klipper on the Sapphire has a lot of special steps that are unique to the Robin Nano 1.2 board that we use.

You need to follow the klipper install guide: https://www.klipper3d.org/Installation.html , but during the make menuconfig section you need to match this:

Then the make command failed for me. Previously, when running one of the earlier scripts I got a message that looked more like a warning than a true error:

InRelease' changed its 'Suite' value from 'stable' to 'oldstable' N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.

This turned out to be important and you need to run: sudo apt update --allow-releaseinfo-change

Which then allows you to update all the packages. The subsequent errors to make can be resolved by installing the missing packages using apt-get install <package>.

Once make can run successfully, you still need to run (do not attempt to flash the mcu):

./scripts/update_mks_robin.py ./out/klipper.bin ./out/Robin_nano35.bin

Then you can use something like Filezilla to SFTP the Robin_nano35.bin file to your computer and then onto a microSD card to put in the Robin nano. If the LCD screen never goes blank, you will likely have to repeat the process starting from make, but before you do run:

make clean

If the screen does go blank, it means the update succeeded so you should remove the SD card and restart the MCU

Fixing my Blogger Theme

noreply@blogger.com (Sarit) — Tue, 18 Jan 2022 06:35:00 +0000

I figured out why I didn't have the same configuration options in my theme as others. Turns out blogger has a completely customizable theme configuration engine (mind blown). You can define variables and metadata about them in your HTML code and then blogger will scan the code and build a dynamic UI for you to tweak it.

Details are here: https://www.freshtechtips.com/2021/09/blogger-blogspot-template-custom-variables.html

My issue was that there was no way to style the fonts for the different heading types in blog posts:

The lesser headings turned out to be bigger than the major ones. This turned out to be a bad CSS rule, but still its good to be able to change it.

So now my headings look like this:

Major Heading

Heading

Subheading

Minorheading

Paragraph

Normal

Source code syntax highlighting on Blogger

noreply@blogger.com (Sarit) — Tue, 18 Jan 2022 05:53:00 +0000

Making code look nice on blogger is pretty hard. Most of the time we use a fancy IDE with syntax highlighting to write the code, but once we want to talk about it here on blogger, all we can show is mono-space text... yuck! The best thing I've found so far is to add hightlight.js as part of the theme HTML. Then whenever you add HTML in the form of:

<pre><code>YOUR CODE GOES HERE</code></pre>

it will highlight it. However if you have HTML in the code, you will still need to escape it first using something like https://www.freeformatter.com/html-escape.html. Also highlight.js will try to figure out the language that you're code is in, but if you want to force it, you can by adding a class="language-<ALIAS>" attribute to the <code> element. For instance, to do Typescript:

<pre><code class="language-typescript">class MyClass extends SubClass {
  private field;
  constructor() {}
}</code></pre>

And you'd get something like this:

class MyClass extends SubClass {
  private field;
  constructor() {}
}

Configuration

Blogger doesn't allow <link> elements in the post template so we have to edit the whole theme HTML to add the CSS styles. Goto the dashboard and click on "Theme" then click on the down arrow next to "Customize"

Then click on "Edit HTML"

And paste in the following code somewhere in the <head> section of the HTML

<link href='https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@latest/build/styles/stackoverflow-dark.min.css' rel='stylesheet'/>
<script src='https://cdn.jsdelivr.net/gh/highlightjs/cdn-release@latest/build/highlight.min.js'/>
<script>hljs.highlightAll();</script>

Like this:

You can find other themes on the highlight.js site, but make sure you use the CDN path like I did so you will always get the latest version.

Automating Crashplan Updates

noreply@blogger.com (Sarit) — Sat, 25 Dec 2021 02:08:00 +0000

In my previous post, I showed the run command I used to get Crashplan running on my QNAP device. Fast forward a few months and Crashplan stopped working because it looks like they have updated their app. Unfortunately, the container image cannot update itself so I wrote a script that goes through the same process described here: https://github.com/jlesage/docker-crashplan-pro#docker-image-update

#!/bin/sh

echo "========================"
echo "Updating container image"
echo "========================"

docker pull jlesage/crashplan-pro

echo "=================="
echo "Stopping container"
echo "=================="

docker stop crashplan-pro

echo "======================"
echo "Removing the container"
echo "======================"

docker rm crashplan-pro

echo "================="
echo "Run the container"
echo "================="

docker run -d --name=crashplan-pro -e USER_ID=0 -e GROUP_ID=0 -e CRASHPLAN_SRV_MAX_MEM=12G -p 5800:5800 -p 5900:5900 -v /share/docker/appdata/crashplan-pro:/config:rw -v /share:/share:ro jlesage/crashplan-pro

Be sure to chmod +x the file so you can run it.

Crashplan on QNAP

noreply@blogger.com (Sarit) — Sat, 25 Dec 2021 01:52:00 +0000

Turns out there's a nice docker image that can run on QNAP, but to really use it to its full potential you can't use Container Station because it won't let you map the /share drive into the container.

I use the https://github.com/jlesage/docker-crashplan-pro image and it works wonderfully. This issue really helped: https://github.com/jlesage/docker-crashplan-pro/issues/8

The solution is to SSH into your QNAP, and manually run the docker command. Container Station will then be able to "see" your running container so you can manage it afterwards.

The command to run is:

docker run -d \
--name=crashplan-pro \
-e USER_ID=0 \
-e GROUP_ID=0 \
-e CRASHPLAN_SRV_MAX_MEM=12G \
-p 5800:5800 \
-p 5900:5900 \
-v /share/docker/appdata/crashplan-pro:/config:rw \
-v /share:/share:ro \
jlesage/crashplan-pro

[3D Printer Series] Calibrating a cheap high temp thermistor for accuracy

noreply@blogger.com (Sarit) — Mon, 15 Mar 2021 08:11:00 +0000

If you want to start printing with more functional filaments like ABS, Nylon, Polycarbonate, and even some PETGs you'll definitely want to upgrade to an an all-metal hotend and keep that PTFE tube from getting over 250C where it will start to burn/breakdown. Even with that out of the way you might still run into an issue where your thermistor can't reliably read high temperature either.

In Klipper, I was getting a "Requested temperature out or range" error when trying to print higher than 250C. After updating my printer.cfg to support higher temps, I then started to get:

MCU 'mcu' shutdown: ADC out of range.

Turns out my stock thermistor starts throwing out invalid numbers once it goes out of the temperature range. To fix this I purchased the WINSINN 3D Printer HT-NTC100K Thermistor for Sensor Heater Block Hotend Extruder - 3x15 3950 Wiring Female 2Pin XH2.54 (Pack of 5Pcs) . Installing it is pretty easy, but I do recommend that you take the time to attach your own connectors if the ones that come with aren't your typical ones.

The hard part however was configuring it in Klipper. There is a built-in config for "NTC 100K beta 3950" which is technically what this thermistor is however, I would recommend people stay away from using it. It turns out that these kind of thermistors work by a property where their resistance changes due to heat. The change though is not linear but curved and the "beta 3950" part of that description is a mathematical description of that curve. Unfortunately, that curve only applies to a very narrow temperature range at the lower end of the spectrum, totally useless for our needs. The Klipper algorithm assumes this beta is correct for the whole range and, in the end, your thermistor will be about 15-20C off at the upper range which is pretty bad.

The best way to configure a thermistor is to actually use it's resistance to temperature table found in the thermistor's datasheet. The one I bought didn't provide one, but I found one that's pretty much the same here: https://www.makeralot.com/download/Reprap-Hotend-Thermistor-NTC-3950-100K.pdf

Armed with the table, I then had to configure Klipper to use a custom [adc_temperature custom_name] section. The name you put for custom_name becomes the "sensor_type" parameter under the [extruder] section. As you can see I used "winsinn_ht_ntc100k" below. You can copy and paste the code at the bottom anywhere in your printer.cfg as long as it is above the [extruder] section.

Results: Using a thermocouple equipped multimeter, I got consistently no more than 1C difference between this custom config and the thermocouple wedged in the slot of the dragon hotend heatblock where the heater cartridge is. I waited till the temps stabilized before comparing. I also used the klipper command QUERY_ADC NAME=extruder PULLUP=4700 to verify the resistance at various temps and they were in fact matching the table in the datasheet very closely.

[adc_temperature winsinn_ht_ntc100k]

temperature1: -30

temperature2: -29

temperature3: -28

temperature4: -27

temperature5: -26

temperature6: -25

temperature7: -24

temperature8: -23

temperature9: -22

temperature10: -21

temperature11: -20

temperature12: -19

temperature13: -18

temperature14: -17

temperature15: -16

temperature16: -15

temperature17: -14

temperature18: -13

temperature19: -12

temperature20: -11

temperature21: -10

temperature22: -9

temperature23: -8

temperature24: -7

temperature25: -6

temperature26: -5

temperature27: -4

temperature28: -3

temperature29: -2

temperature30: -1

temperature31: 0

temperature32: 1

temperature33: 2

temperature34: 3

temperature35: 4

temperature36: 5

temperature37: 6

temperature38: 7

temperature39: 8

temperature40: 9

temperature41: 10

temperature42: 11

temperature43: 12

temperature44: 13

temperature45: 14

temperature46: 15

temperature47: 16

temperature48: 17

temperature49: 18

temperature50: 19

temperature51: 20

temperature52: 21

temperature53: 22

temperature54: 23

temperature55: 24

temperature56: 25

temperature57: 26

temperature58: 27

temperature59: 28

temperature60: 29

temperature61: 30

temperature62: 31

temperature63: 32

temperature64: 33

temperature65: 34

temperature66: 35

temperature67: 36

temperature68: 37

temperature69: 38

temperature70: 39

temperature71: 40

temperature72: 41

temperature73: 42

temperature74: 43

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temperature76: 45

temperature77: 46

temperature78: 47

temperature79: 48

temperature80: 49

temperature81: 50

temperature82: 51

temperature83: 52

temperature84: 53

temperature85: 54

temperature86: 55

temperature87: 56

temperature88: 57

temperature89: 58

temperature90: 59

temperature91: 60

temperature92: 61

temperature93: 62

temperature94: 63

temperature95: 64

temperature96: 65

temperature97: 66

temperature98: 67

temperature99: 68

temperature100: 69

temperature101: 70

temperature102: 71

temperature103: 72

temperature104: 73

temperature105: 74

temperature106: 75

temperature107: 76

temperature108: 77

temperature109: 78

temperature110: 79

temperature111: 80

temperature112: 81

temperature113: 82

temperature114: 83

temperature115: 84

temperature116: 85

temperature117: 86

temperature118: 87

temperature119: 88

temperature120: 89

temperature121: 90

temperature122: 91

temperature123: 92

temperature124: 93

temperature125: 94

temperature126: 95

temperature127: 96

temperature128: 97

temperature129: 98

temperature130: 99

temperature131: 100

temperature132: 101

temperature133: 102

temperature134: 103

temperature135: 104

temperature136: 105

temperature137: 106

temperature138: 107

temperature139: 108

temperature140: 109

temperature141: 110

temperature142: 111

temperature143: 112

temperature144: 113

temperature145: 114

temperature146: 115

temperature147: 116

temperature148: 117

temperature149: 118

temperature150: 119

temperature151: 120

temperature152: 121

temperature153: 122

temperature154: 123

temperature155: 124

temperature156: 125

temperature157: 126

temperature158: 127

temperature159: 128

temperature160: 129

temperature161: 130

temperature162: 131

temperature163: 132

temperature164: 133

temperature165: 134

temperature166: 135

temperature167: 136

temperature168: 137

temperature169: 138

temperature170: 139

temperature171: 140

temperature172: 141

temperature173: 142

temperature174: 143

temperature175: 144

temperature176: 145

temperature177: 146

temperature178: 147

temperature179: 148

temperature180: 149

temperature181: 150

temperature182: 151

temperature183: 152

temperature184: 153

temperature185: 154

temperature186: 155

temperature187: 156

temperature188: 157

temperature189: 158

temperature190: 159

temperature191: 160

temperature192: 161

temperature193: 162

temperature194: 163

temperature195: 164

temperature196: 165

temperature197: 166

temperature198: 167

temperature199: 168

temperature200: 169

temperature201: 170

temperature202: 171

temperature203: 172

temperature204: 173

temperature205: 174

temperature206: 175

temperature207: 176

temperature208: 177

temperature209: 178

temperature210: 179

temperature211: 180

temperature212: 181

temperature213: 182

temperature214: 183

temperature215: 184

temperature216: 185

temperature217: 186

temperature218: 187

temperature219: 188

temperature220: 189

temperature221: 190

temperature222: 191

temperature223: 192

temperature224: 193

temperature225: 194

temperature226: 195

temperature227: 196

temperature228: 197

temperature229: 198

temperature230: 199

temperature231: 200

temperature232: 201

temperature233: 202

temperature234: 203

temperature235: 204

temperature236: 205

temperature237: 206

temperature238: 207

temperature239: 208

temperature240: 209

temperature241: 210

temperature242: 211

temperature243: 212

temperature244: 213

temperature245: 214

temperature246: 215

temperature247: 216

temperature248: 217

temperature249: 218

temperature250: 219

temperature251: 220

temperature252: 221

temperature253: 222

temperature254: 223

temperature255: 224

temperature256: 225

temperature257: 226

temperature258: 227

temperature259: 228

temperature260: 229

temperature261: 230

temperature262: 231

temperature263: 232

temperature264: 233

temperature265: 234

temperature266: 235

temperature267: 236

temperature268: 237

temperature269: 238

temperature270: 239

temperature271: 240

temperature272: 241

temperature273: 242

temperature274: 243

temperature275: 244

temperature276: 245

temperature277: 246

temperature278: 247

temperature279: 248

temperature280: 249

temperature281: 250

temperature282: 251

temperature283: 252

temperature284: 253

temperature285: 254

temperature286: 255

temperature287: 256

temperature288: 257

temperature289: 258

temperature290: 259

temperature291: 260

temperature292: 261

temperature293: 262

temperature294: 263

temperature295: 264

temperature296: 265

temperature297: 266

temperature298: 267

temperature299: 268

temperature300: 269

temperature301: 270

temperature302: 271

temperature303: 272

temperature304: 273

temperature305: 274

temperature306: 275

temperature307: 276

temperature308: 277

temperature309: 278

temperature310: 279

temperature311: 280

temperature312: 281

temperature313: 282

temperature314: 283

temperature315: 284

temperature316: 285

temperature317: 286

temperature318: 287

temperature319: 288

temperature320: 289

temperature321: 290

temperature322: 291

temperature323: 292

temperature324: 293

temperature325: 294

temperature326: 295

temperature327: 296

temperature328: 297

temperature329: 298

temperature330: 299

temperature331: 300

resistance1: 1733200

resistance2: 1630408

resistance3: 1534477

resistance4: 1444903

resistance5: 1361220

resistance6: 1283000

resistance7: 1209327

resistance8: 1140424

resistance9: 1075949

resistance10: 1015588

resistance11: 959050

resistance12: 906011.7

resistance13: 856288.3

resistance14: 809650.6

resistance15: 765886.5

resistance16: 724800

resistance17: 685650.7

resistance18: 648892.9

resistance19: 614364.9

resistance20: 581916.9

resistance21: 551410

resistance22: 522690.8

resistance23: 495667.4

resistance24: 470228.6

resistance25: 446271.4

resistance26: 423700

resistance27: 402056

resistance28: 381665.8

resistance29: 362448.8

resistance30: 344330.1

resistance31: 327240

resistance32: 311039.7

resistance33: 295750.6

resistance34: 281315.7

resistance35: 267682

resistance36: 254800

resistance37: 242582.7

resistance38: 231032.1

resistance39: 220108

resistance40: 209772.4

resistance41: 199990

resistance42: 190557.8

resistance43: 181631.9

resistance44: 173182.2

resistance45: 165180.4

resistance46: 157600

resistance47: 150425.3

resistance48: 143623.4

resistance49: 137172.6

resistance50: 131052.8

resistance51: 125245

resistance52: 119658.2

resistance53: 114355.9

resistance54: 109322.1

resistance55: 104541.5

resistance56: 100000

resistance57: 95819.1

resistance58: 91839.2

resistance59: 88049.4

resistance60: 84439.5

resistance61: 81000

resistance62: 77623.8

resistance63: 74409.1

resistance64: 71347.2

resistance65: 68430.1

resistance66: 65650

resistance67: 62983.8

resistance68: 60442

resistance69: 58018.1

resistance70: 55706

resistance71: 53500

resistance72: 51370.8

resistance73: 49339.1

resistance74: 47399.8

resistance75: 45548.3

resistance76: 43780

resistance77: 42055.5

resistance78: 40409.2

resistance79: 38836.9

resistance80: 37335

resistance81: 35899.9

resistance82: 34616

resistance83: 33385.5

resistance84: 32205.9

resistance85: 31074.8

resistance86: 29990

resistance87: 28905.3

resistance88: 27866

resistance89: 26870

resistance90: 25915.3

resistance91: 25000

resistance92: 24109.9

resistance93: 23256.5

resistance94: 22438.1

resistance95: 21653.1

resistance96: 20900

resistance97: 20174.1

resistance98: 19477.4

resistance99: 18808.7

resistance100: 18166.6

resistance101: 17550

resistance102: 16945.9

resistance103: 16365.9

resistance104: 15808.9

resistance105: 15273.9

resistance106: 14760

resistance107: 14281.3

resistance108: 13820.6

resistance109: 13377.4

resistance110: 12950.7

resistance111: 12540

resistance112: 12134.7

resistance113: 11744.7

resistance114: 11369.4

resistance115: 11008

resistance116: 10660

resistance117: 10324.3

resistance118: 10001

resistance119: 9689.5

resistance120: 9389.3

resistance121: 9100

resistance122: 8817.1

resistance123: 8544.4

resistance124: 8281.6

resistance125: 8028.3

resistance126: 7784

resistance127: 7553.8

resistance128: 7331.6

resistance129: 7117.2

resistance130: 6910

resistance131: 6710

resistance132: 6526.5

resistance133: 6349

resistance134: 6177.2

resistance135: 6010.9

resistance136: 5850

resistance137: 5683.2

resistance138: 5522.1

resistance139: 5366.3

resistance140: 5215.6

resistance141: 5070

resistance142: 4929.1

resistance143: 4792.8

resistance144: 4661

resistance145: 4533.4

resistance146: 4410

resistance147: 4290.6

resistance148: 4175.1

resistance149: 4063.2

resistance150: 3954.9

resistance151: 3850

resistance152: 3741

resistance153: 3635.7

resistance154: 3533.8

resistance155: 3435.3

resistance156: 3340

resistance157: 3255

resistance158: 3172.6

resistance159: 3092.7

resistance160: 3015.2

resistance161: 2940

resistance162: 2863.4

resistance163: 2789.3

resistance164: 2717.3

resistance165: 2647.6

resistance166: 2580

resistance167: 2514.4

resistance168: 2450.7

resistance169: 2389

resistance170: 2329.1

resistance171: 2271

resistance172: 2213.5

resistance173: 2157.7

resistance174: 2103.5

resistance175: 2051

resistance176: 2000

resistance177: 1951.3

resistance178: 1904

resistance179: 1858

resistance180: 1813.4

resistance181: 1770

resistance182: 1731.9

resistance183: 1694.7

resistance184: 1658.6

resistance185: 1623.3

resistance186: 1589

resistance187: 1552

resistance188: 1516

resistance189: 1481.1

resistance190: 1447.1

resistance191: 1414

resistance192: 1381.2

resistance193: 1349.4

resistance194: 1318.4

resistance195: 1288.3

resistance196: 1259

resistance197: 1230.1

resistance198: 1201.9

resistance199: 1174.5

resistance200: 1147.9

resistance201: 1122

resistance202: 1095.6

resistance203: 1069.9

resistance204: 1044.9

resistance205: 1020.6

resistance206: 997

resistance207: 975.7

resistance208: 955

resistance209: 934.8

resistance210: 915.1

resistance211: 896

resistance212: 875

resistance213: 854.7

resistance214: 834.9

resistance215: 815.7

resistance216: 797

resistance217: 780.6

resistance218: 764.6

resistance219: 749

resistance220: 733.8

resistance221: 719

resistance222: 702.9

resistance223: 687.3

resistance224: 672.1

resistance225: 657.4

resistance226: 643

resistance227: 630.2

resistance228: 617.7

resistance229: 605.5

resistance230: 593.6

resistance231: 582

resistance232: 571.7

resistance233: 561.7

resistance234: 551.9

resistance235: 542.3

resistance236: 533

resistance237: 522.5

resistance238: 512.2

resistance239: 502.2

resistance240: 492.5

resistance241: 483

resistance242: 473.3

resistance243: 463.9

resistance244: 454.7

resistance245: 445.7

resistance246: 437

resistance247: 428.4

resistance248: 420

resistance249: 411.8

resistance250: 403.8

resistance251: 396

resistance252: 388.4

resistance253: 381

resistance254: 373.9

resistance255: 366.8

resistance256: 360

resistance257: 353.3

resistance258: 346.7

resistance259: 340.3

resistance260: 334.1

resistance261: 328

resistance262: 322

resistance263: 316.1

resistance264: 310.4

resistance265: 304.8

resistance266: 299.3

resistance267: 294

resistance268: 288.8

resistance269: 283.6

resistance270: 278.6

resistance271: 273.7

resistance272: 268.9

resistance273: 264.2

resistance274: 259.6

resistance275: 255.1

resistance276: 250.7

resistance277: 246.4

resistance278: 242.2

resistance279: 238

resistance280: 234

resistance281: 230

resistance282: 226.2

resistance283: 222.3

resistance284: 218.6

resistance285: 215

resistance286: 211.4

resistance287: 207.9

resistance288: 204.5

resistance289: 201.1

resistance290: 197.8

resistance291: 194.6

resistance292: 191.4

resistance293: 188.3

resistance294: 185.3

resistance295: 182.3

resistance296: 179.4

resistance297: 176.5

resistance298: 173.7

resistance299: 171

resistance300: 168.3

resistance301: 165.6

resistance302: 163

resistance303: 160.4

resistance304: 157.9

resistance305: 155.5

resistance306: 153.1

resistance307: 150.7

resistance308: 148.4

resistance309: 146.1

resistance310: 143.9

resistance311: 141.7

resistance312: 139.6

resistance313: 137.5

resistance314: 135.4

resistance315: 133.4

resistance316: 131.4

resistance317: 129.5

resistance318: 127.5

resistance319: 125.7

resistance320: 123.8

resistance321: 122

resistance322: 120.2

resistance323: 118.5

resistance324: 116.8

resistance325: 115.1

resistance326: 113.4

resistance327: 111.8

resistance328: 110.2

resistance329: 108.6

resistance330: 107.1

resistance331: 105.6

[3D Printer Series] Volumetric Flow

noreply@blogger.com (Sarit) — Sun, 21 Feb 2021 11:14:00 +0000

To see the max speed at which you can print you need the volumetric speed at which you can print.

The max volume for the Dragon w/ SUNLU Red PLA is 20mm^3/s. The true max speed is actually a bit higher but I step it back a fair amount to make sure I get good repeatability.

First set your extruder temp (mine is 205C)

Gcode to test various extrusion speeds:

G91
; Run the following multiple times until the extruder
; starts skipping. Increase the F# by 100 each time
G1 E250 F300 ; extrude 250mm at 300mm/min

My max was F600, but I back it down to F500.

To calculate volumetric flow we take feedrate (500) x filament cross sectional area pi * (1.75mm/2)^2 = 2.405 => 20mm^3/s.

[3D Printer Series] Hotend cooling

noreply@blogger.com (Sarit) — Mon, 18 Jan 2021 06:48:00 +0000

Hotend Cooling and Testing

The hotend on the Sapphire Plus is supposedly pretty bad but so far I haven't experienced any clogging that wasn't my own fault (didn't push the PTFE tube all the way in) even on an 8 hour print. This is with PLA so perhaps the hotend is sufficient for the low temps (205C). My plan was always to start printing some higher temp filament like PETG/ABS/ASA and perhaps even PC and Nylon so I knew I would need an all metal hotend at some point. I decided on the Triangle Labs Dragon, specifically the high flow version. This seemed like a good compromise between performance and price.

The Mount

To use it I would need to print a bracket to be able to use it on the Sapphire Plus. I chose The Mint Mount by 3D-One. This mount was fairly recently developed to be compatible with the dragon. After printing out the mount and installing the dragon, I did notice some gaps around the hotend which in my mind seemed like wasted cooling air flow so I embarked on a test to see what configurations would yield the best performance.

Mount seems to have gaps that may waste cooling airflow

The test rig

I purchased the Kaiweet Multimeter because it came with one of those tiny glass bead thermistors and I needed a better meter that could do things like true RMS and could measure PWM signals. For the price this is a really good deal. One simple feature that I love is that it has a built in stand!

Next I transferred the components from the original hotend to this mount. For the cooling fan, I purchased the Anvision 40mmx10mm 24v fan (currently sold out on amazon) because it seemed like they made fairly quiet fans. I connected the fans by crimping on some JST-SM connectors (the connector I use for all my hotend connections).

I then placed the thermistor from my multimeter fairly deep into the hotend. I used my fingers to gauge exactly how far the thermistor should go as you can see in the photo below.

Here's what it looks like with the thermistor inserted. Its a fairly snug fit so I doubt it will move during my tests.

Here's my mess and my full testing setup.

Test Parameters

I tested fan pull and push as well as with and without gaps, 4 total combinations. To fill the gaps I just stuffed some small pieces of tissue into the gaps between the cage and the mount. Since I knew the replacing of fans and the insertion/removal of tissue might move the thermistor, I figured the best way to verify it didn't was to just repeat the first test and see if I got the same results.

The room temp was 70F (my meter was in F). For each test run, I set the hotend temp to 205C (Klipper uses C) and I waited till the temp on my meter to stabilize (~ 5min) and then set a timer for 5 more minutes to confirm the temp didn't change. After each test I turned off the heater and setup the hotend for the next and waited for the temps to get down to the low eighties F before starting up the heater again.

Test Results

	Gaps Open	Gaps Filled
Fan Push	99F	95F
Fan Pull	90F	93F

Conclusion

It looks like for my particular setup Fan Pull with the gaps open proved to be the winner. What's interesting is that there's no consistency between whether you should have gaps filled or not. That's why it's important to do your own tests. Your hotend geometry, the fan you use, and the mount are all variables that affect cooling performance. Changing any one of them and you could very well get different results.

Choosing a 3D Printer

noreply@blogger.com (Sarit) — Tue, 29 Dec 2020 15:37:00 +0000

Key Factors

It's important to get a list of factors that are relevant to you when deciding on what printer to by. Here are mine:

Price < $1000
Speed, can print accurately at relatively high speeds
Quality
Large build plate
Serviceability
Support/Community support

For me, based on some reviews on YouTube and Facebook, I decided to go with the TwoTrees Sapphire Plus. It seemed to have the best hardware for a machine with a 300+mm build plate. Because it’s a coreXY printer with linear rails it has the potential to move swiftly and accurately. The biggest downside is that it’s not beginner friendly nor is there any support from TwoTrees except from their Facebook Group, which in most cases is community support not manufacturer.

I also considered the ender 5 plus but learned that it’s not a true corexy printer. I also looked at the SecKitGo but that felt like a bigger project and the developer had stopped taking orders.

Multiple versions floating around

If you want to order one, I don’t suggest you use my amazon affiliate link, instead you can get the same one I got from 3dprintersonline.com which is much cheaper. If you do so be aware that you might not be getting the true 'latest' version that at the time of this writing supposedly has a glass bed and a synchronization belt between the 2 z-axis motors. The latest one according to other accounts can be got from gearbest (pay more) and/or ordering from the china warehouse. I didn't feel like waiting or paying more so I went with 3dprintersonline.com.

3dprintersonline.com

This site seems a little sketchy to me but searching the net revealed they are legitimate. For the purposes of their relationship with TwoTrees, they are more like a marketplace that takes orders for them and funnels those orders directly to the TwoTrees warehouses for fulfillment. My order seemed to be delayed getting out the door so it took a couple of emails to 3dprintersonline who then emailed their rep at TwoTrees to check on the shipment. Bear in mind this was after the Black Friday sale so your experience might be better.

Would I choose the Sapphire Plus again?

Knowing what I know now, I probably would but for the first time 3d printer owner who doesn't want to tinker with one I would 100% not recommend it. If you just want something that works, you're better off with a Prusa ($$$) or something like an Ender 3 V2 (affiliate link) which has much larger community support. I have a lot of technical experience setting up machines for accuracy and can read code/program software. If you're someone like me, this is a good route to take and should reward you with a good foundation to build a fast reliable and accurate machine. If you're ready to take the red pill and join me, please continue reading my blog series.

Affiliate links

I'm not paid to promote any of these products, but if you'd like to support me, please use my amazon affiliate links below. You don't even need to purchase the item listed. As long as you purchase something after using the link, I will get something out of it. Also note that using the link does not change how much you pay (no cost to you).

3D Printing - Having an Opinionated way of doing things

noreply@blogger.com (Sarit) — Tue, 29 Dec 2020 09:43:00 +0000

In land of consumer grade (read cheap) 3d printers, there's quite a lot of information and while it's fairly good and accurate, being objective about the information given will lead many down the road of bad choices based on their previous (possibly good) choices.

To give some context a lot of this technology is a potpourri of tech from all over the place. It comes from 3d printer companies, open source developers, and component hardware companies from both the west and the east. Each one adding new features all the time. So when you get your 3d printer, and assuming you want to get the most out of it, you'll have to pick and and choose which features from which components you will leverage. This task becomes monumentally huge when you consider how the various bits of hardware and software play together (and more importantly when they don't play together).

Most content I find on Youtube and the web tends to be objective on this matter. They will go through all the features of whatever component they are reviewing, but that doesn't really help the common 3d printer user that has a particular machine, setup a particular way, used in their particular workflow.

I will try to document my highly opinionated 3d printer journey and explain the reasons for the choices I made so that others can gain a better context of how they should setup and use their printers.

Why your SawStop riving knife still isnt aligned

noreply@blogger.com (Sarit) — Mon, 09 Oct 2017 05:25:00 +0000

My SawStop PCS tablesaw has a pretty fussy riving knife adjustment system. You have to crank the blade up to check alignment and then crank it back down to be able to adjust the bolts and of course every time you tighten the bolts you move the knife out of alignment. So back and forth you go crank, loosen, align, crank, tighten, crank, loosen, align,... Then once you’ve got it just right, and you crank the blade back down to a reasonable height to cut some 3/4” plywood the knife seems out of alignment. What gives!?

Turns out that the knife holder isn’t exactly tilted in the same plane as the saw blade. It’s off by the slightest half of a degree. That doesn’t sound like much, but when the difference between the kerf and the riving knife is measured in .001”, that’s huge. If you have this problem it will seem like either you have to push harder to push the workpiece past the riving knife or the workpiece seems to want to drift away from the fence and cause burns along the cut. I had the latter problem. SawStop surprisingly has no mechanism to adjust the tilt. What I did to fix this was to add a couple of pieces of tape as shims to tilt the knife in the opposing direction as in the photos below.

Adding blue tape to the upper clap area

Adding blue tape to the lower clamp area on the opposite side

My new favorite pen: OfficeDepot 1.0mm Ballpoint

noreply@blogger.com (Sarit) — Sun, 29 May 2016 01:01:00 +0000

Seems a bit strange to most people to review a ballpoint pen, but I've been keeping track of the different pens I've used over the years and thought I had settled on the Uni-ball brand of pens. Especially their JetStream line of pens, but they always had a bit of a scratching feel as you run the tip across the paper. The OfficeDepot pen however seems to glide effortlessly across the page. They are also pretty cheap at less than $5 for a pack of 36. I would say the only drawback is the thinness of the pen itself. It needs a chunkier body with a grip to make writing comfortable.

Is Appleseed: Alpha's Deunan modelled after Divergent's Shailene Woodley?

noreply@blogger.com (Sarit) — Sun, 22 Nov 2015 06:28:00 +0000

What do you think?

Installing a phone holder in my S2000

noreply@blogger.com (Sarit) — Mon, 07 Sep 2015 06:48:00 +0000

The Problem

Anyone with a Honda S2000 will tell you there's practically no logical place to mount a phone in it other than on the windshield with suction cups. Sure there are solutions that allow you to mount a phone down by the gear shift, but if I have look down that far to see my screen, I might as well leave my phone in the cupholder. I also don't like having the phone obscuring part of the windshield nor the possibility that suction cups might fail as I'm making a high G turn. What I really want is a way to mount the phone on the vast emptiness of the dash. Turns out there's a company that's figured out how to do just that with only minor modifications in hidden areas to my S (all of which can be visually returned back to stock).

The Goods

Modifry is a company that makes cool custom stuff just for the S2000. They have a custom bracket, that attaches between the bezel of my console and the dash. The other end of the bracket has hole patterns for various mounting solutions. I opted for the ProClip holder which, although a bit pricey, had the most convenient way of inserting and removing my phone (the phone just slides in like a holster for a gun).

ProClip iPhone5 holder (left) and Modify S2000 Dash Bracket (right)

Installation

Blue painter's tape protects the dash while I
remove the hidden inner lip of plastic

There's a very detailed sheet of instructions that come with the bracket. I was able to follow them pretty easily, however someone on youtube posted a howto which helped immensely with the process. I was able to put several layers of tape over a '"5 in 1 painter's tool" and use that instead of a professional pry bar they recommended. Cutting the hidden plastic wasn't nearly as scary as others had mentioned on forums. I pretty much cut away all I needed on my first try. I did take several scoring passes with my utility knife until it finally went completely through the plastic. I did cover the areas I was protecting w/ blue painter's tape, but I'm not sure how much protection that really provided since my knife could have easily pierced through both it and the vinyl dash. I also had to scrounge around my nuts & bolts organizer for something that would fasten the ProClip holder to the bracket. I'm just using some nuts and bolts w/o any thread locking compound so we'll have to see if any of them get loose over time.

Final thoughts

The whole setup looks like the picture below. As you can see, the bracket puts the phone in just the right position without obstructing any view of the windshield. The ProClip seems like a good fit for my phone, but the level of effort they put into telling you that you can't return it once you use it, is a bit off putting, especially for such a relatively expensive product. I could understand that being the case for cheap low margin knockoffs, but ProClip seems to be marketing itself as a premium solution. As such, I would expect a much more liberal return policy. Just my 2 cents.

ProClip mounted to the Modifry Dash Br

BaconFest 2015 in San Jose

noreply@blogger.com (Sarit) — Sun, 06 Sep 2015 00:11:00 +0000

I love bacon, but I don't think I'll go to the BaconFest again. The food was overpriced, the quantities were too small, and the lines were way too long. There were very few creative uses of bacon available from the food truck vendors. Most offered your standard fair food truck foods with just the addition of some bacon on top. We picked up some bacon peanut brittle, a bacon bouquet (a few strips of bacon wrapped in paper), porky fries, Vietnamese bacon bah mi sandwich, and the stuff you see below. I would have tried some bacon icecream or bacon maple cupcakes, but the kids opted for fruit popsicles instead and I didn't want to wait in yet another long line.

They also showed some pro wrestling which I got some good photos of below.

California Roll with bacon on top

Takoyaki with bacon on top

Real World Tony Stark needs his Real World Arc Reactor

noreply@blogger.com (Sarit) — Wed, 20 May 2015 08:41:00 +0000

If you had to pick a modern equivalent to Iron Man's Tony Stark, I don't think you could do better than Tesla founder Elon Musk. Musk used his success in PayPal to create his own electric car company Tesla Motors, a space company SpaceX, and is involved in a new revolutionary new highspeed train project. Essentially if there's something technological that should be done but nobody dares to do it, you can can bet that Musk is up to the challenge.

Elon Musk

Musk has stated that one of his goals is to make human life multi-planetary. This has led to him start SpaceX and create revolutionary rocket systems cheaper and better than anyone else. People said electric cars couldn't be done so he started Tesla. Others said solar would never be economical, so he helped start SolarCity. If anything could be profitable, then Musk was going to find a way to do it.

Despite all these great achievements, Musk will never realize human life on another planet, nor a completely fossil fuel free economy unless he can find his own version of an arc reactor. It will take an extremely long time until solar becomes economically viable on a country scale (let along global scale) to complete with coal & natural gas prices. You would need fairly high carbon taxes or other subsidies to make fossil fuel based power competitive with renewables. This is why I believe, we can't have a bright future without a significant increase in nuclear power.

I know nuclear scares a lot of people, but bear in mind that we've been using primarily first generation 1960's nuclear reactor designs up until now, and those were the ones that have caused all the problems we've seen in nuclear. Now, all these 1st gen plants are reaching their end of life, and it really would be a lost opportunity if we replaced it with the same thing with the same sets of problems. What we really need is a nuclear renaissance in the development of next generation nuclear reactors.

It wasn't until recently when I discovered a forgotten type of nuclear reactor that was radically different from the light water reactors (LWR) we see today. It's known as the liquid fluoride thorium reactor (LFTR, pronounced like "lifter") and it's design may be the key to safe, cheap, low waste, proliferation resistant power. In this design, the nuclear fuel is an element known as thorium instead of uranium, and it is formed into a fluoride salt and melted into a liquid in the reactor. In typical solid fueled reactors, the nuclear decay and fission products build up inside the fuel pellets. This contamination, prevents all the energy in the pellet from being released. In fact, at most about 3% of the energy in the fuel pellet gets used before it is replaced. In LFTR, the liquid fuel can be chemically separated, allowing the thorium to be burned up completely as energy. This drastically reduces the waste generated and managing waste is a significant portion of the cost of nuclear. Additionally, since the fuel is designed to be in the melted state, there is no worries about nuclear meltdown (its already, and should be melted).

Thorium, itself is pretty interesting. Apparently, mining companies and countries around the world are desperate for a source of rare earth elements (REE) used in high tech equipment. A large subset of these REE's (the more expensive heavy ones) exist predominately in a type of rock known as monazite which we get as a byproduct of mining for other elements like iron, titanium, etc, and this monazite often has thorium in it. Unfortunately, in the 50's, thorium was classified as a nuclear source material which made handling, storing, transporting, and disposal of it so much of a burden that thorium rich byproducts were being dumped back into the ground from which they were mined. That meant that the production of REE's was drastically reduced as only very low thorium bearing byproducts would be processed for REE extraction.

China, on the other hand, did not fear the thorium content and eventually became the sole supplier of the heaviest REE's for the world, purely by refining their byproducts of iron mining. Today, companies that depend on a stable supply of certain REE's must relocate their manufacturing to China. China has even stated that they do not wish to be the sole provider of the world's REE and may begin severely limiting or even eliminating its exports.

A thorium fueled, reactor would create not only a demand for thorium, but an escape from the environmental and legal burdens that come with processing thorium and REE rich byproducts. A nice win-win solution.

What Musk needs, is a cheap, clean energy solution. And wouldn't it be great bonus if you could load it on a spaceship and use it on another planet? Amazingly, the LFTR design, with its passive safety, would weigh much less than a typical reactor. Thorium too can be found on the moon and Mars and satellites can easily scan the surface for rich deposits. So Elon, what are you waiting for?

Fixing my Fridge for Free

noreply@blogger.com (Sarit) — Sun, 12 Apr 2015 07:06:00 +0000

My fridge started acting up recently. The fridge compartment was warm but the freezer compartment was working fine. Searching online, it seems that most common reason for this is a faulty defrost system that causes the evaporator coils in the freezer to frost up with ice until no more air can be diverted to the fridge section. This wasn't the case for me since the evaporator coils looked fine to me. Placing my hand next to the vent that lets the cold air from the freezer into the fridge, I didn't notice any cold air, even though the fan in the freezer was still blowing air around. This led me to believe that there might be something wrong with the venting that controls how much cold air to let into the fridge.

Luckily, you can lookup you fridge model and get the parts list. The part I needed was this:

Also known as a "diffuser". Too bad its almost $90. You might be able to find other places a little bit cheaper, but no much.

If you search on youtube with the part number, you can sometimes get lucky and get a video of some guy replacing the exact same module. This time, I got super lucky, and found a guy who figured out why these diffusers fail, and sold an improved metal replacement part to fix it for far less money.

Removing and opening up my own diffuser revealed that it has suffered the same fate:

Too bad, this guy's in the UK and my food in the fridge wasn't gonna last that long so I needed an alternative. What I ended up doing, was epoxying a bent paperclip around the loop at the bottom and breaking off and filing down the little nubs that were now in the way of the paperclip. I then taped it up (apparently masking tape works well for this) and reinstalled it into the fridge. Time will tell if this hack works.