Electrical Musings

Apache2 configuration for embedded PHP in HTML files

2011-05-21T16:38:00.000-07:00

If you want to use PHP scripts on your web server it is a simple thing to add a script inside a page and save it as a .php file extension.

Listing of phpinside.php
<?php

echo "Hello PHP World!"

?>

When this file is browsed if looks like this:
Hello PHP World!

With the default installation of Apache2 and PHP, however, Apache2 does not know to render an html file as a PHP script. If you name the above file phpinside.html, you will instead see elements of the PHP code when you view the file in a browser.

There are thousands of (old) posts for Apache configuration of PHP by editing the httpd.conf file to include HTML as an application/x-http-php type. However, few make note that Apache2 has a new config file structure for Debian (Ubuntu). Refer to the page that I found for a better explanation: Control Escape - Configuring Apache2 on Debian, Ubuntu

Now the "AddType application/x-http-php" directive is in the php5.conf file in the "etc/apache2/mods-enabled" directory.

Edit the file:
sudo gedit /etc/apache2/mods-enabled/php5.conf

Edit the line to include html and htm:

   AddType application/x-httpd-php .php .phtml .php3 .html .htm
   AddType application/x-httpd-php-source .phps

After you have saved the file you then have to restart Apache2.
   sudo /etc/apache2/apache restart

Free CAD/CAM Options

2011-03-16T14:58:00.000-07:00

There was a time when CAD and CAM software was simply not available for anyone without paying a substantial sum of money. The version of AutoCAD 10 (which came on 10 floppies) that I used for a year at MFJ Enterprises to do product documentation cost almost $1000.

Even low quality programs cost upwards of $99 or more. However, in the past few years there have been many new free versions of software available that are high and even professional quality.

Sketchup
Arguably the first really free CAD software that was good quality was Sketchup. Sketchup was written by a company called @Last Software which sold the software for $495. The company wrote a plug-in for Google Earth and soon afterward Google bought the company. In 2006 at Google Developer Day the developers of Sketchup were there presenting the software and giving away free Sketchup socks.

An important feature of Sketchup is that users can write short snippets of code in Ruby to configure or extend the application. This helps get by limitations of the free version of Sketchup like not being able to export to DXF. There are plenty of plug-ins but the quality and features may vary.

AutoCAD WS
Recently AutoDesk came out with a free version of AutoCAD called AutoCAD WS that exists as a web application or browser app in Google Chrome. It is just like AutoCAD (yech!) However by using the download menu files can be saved as DWG or DXF without added plug-ins.

DraftSight
The last newest free 2D CAD package to arrive is called DraftSight from Daussault Systemes (the company that makes Solidworks). This is a stand alone application that has a small footprint and can be downloaded quickly. Unfortunately this software is much like AutoCAD and not like Solidworks. However it is just as capable as AutoCAD WS and does not exist in the cloud. It also allows loading and saving to MANY different versions of AutoCAD file types. Again, unfortunately it is just like AutoCAD. I wish it more like Solidworks. Hopefully sometime soon there will be a parametric CAD package offered for free.

Note on AutoCAD and Daussault Systemes: AutoDesk has a policy of changing the native file type that AutoCAD uses ever few versions to make users upgrade to the newest version. Daussault Systemes has helped AutoCAD users by releasing software that allows conversion of files from one file type to the other. They also released the Solidworks part modeler as a free plug in for AutoCAD. This software makes AutoCAD work like Solidworks except for creation of assemblies. Let me tell you it is hard to go back to AutoCAD after using the Solidworks part modeler.

InkScape
I have to add Inkscape in here even though it is not really a CAD package. There are now good plug-ins for writing DXF files from Inkscape. The added features inherent to a vector graphics program make InkScape valuable even beyond traditional CAD software.

However work needs to be done on the program to make accurate sizing of objects. Presently the size of an object includes the outline.

Python and MySQL

2011-03-13T00:14:00.000-08:00

Although PHP is used a lot for SQL scripts, Python is a fine alternative.

The commonly used SQL library in Python is MySQLdb. MySQLdb is an thread-compatible interface to the popular MySQL database server that provides the Python database API. (from the documentation)

An example showing the guts of a Python MySQL script.

import MySQLdb

conn = MySQLdb.connect (host = "localhost", user = "root", passwd = "admin", db = "databasename")

db = conn.cursor()

db.execute ( "SELECT * FROM table1")

data = db.fetchall()
#do something with the data

db.close ()

conn.commit ()

conn.close ()

Looking over the code example:

After the import is a connect request to an SQL database. The database in on the localhost and has the default username and password. The the actual database name must be specified. MySQL databases can have multiple databases on one host.

Note that on all the code accessing data or running commands on the database should be inside an exception or "try except" statement. A standard form follows:

import MySQLdb #added import for exit

import sys #added import for exit

try:

some MySQL command

except MySQLdb.Error, e:

print ";Error %d: %s" % (e.args[0], e.args[1])

sys.exit (1)

The next MySQL command is the cursor method which creates a cursor object. Most people like to make the db object the connection and the cursor object as such. But I like to think of the connection as a connection and the cursor as the db itself so I name them appropriately. I'm not sure what else the cursor is used for.

To run a SQL statement you use the execute method. The parameter is a string with the standard string print formating such as "%s %f" %(string,float). However you must use the SQL VALUE keyword. An example follows:

db.execute ("INSERT INTO incident (incident_type, session, lat, lon, alt) \
VALUES (%d, \"%s\", \"%s\", \"%s\", \"%s\")" % \(incident_type[i],sessions[i],locations[i][0],locations[i][1],locations[i][2]))

So basically you can see that use of MySQLdb ends up being an exercise in string creation in SQL command format. Note that in the above example the SQL keywords are in all caps. That is by tradition.

After a SQL statement executes there is usually some output besides updating of the database. To get the output into our Python program we need one of the 3 read methods. In the above example fetchall() is used. The other read methods are fetchone() and rowcount.

The fetchall method grabs all the results in a list which is easy to use in Python. The fetchone method grabs the "next: row in the output. Rowcount is a read only count of the rows in the output. The last two methods are probably not used much as it is easy to iterate a list in Python.

What is with the Ls??? You may see data that should be "60" appear as "60L" after you read it out of a database. When MySQLdb converts a value from SQL unsigned integer to Python it must use a long integer to avoid overflows. To show this conversion an "L" is appended to the value.

Also note that the data read from the database is not in the order that it was entered. Use the ORDER BY keyword in your SQL statements to sort data appropriately.

Next in the example the cursor object is closed. This is important when doing server side scripts so it is included although in this example it is a bit superfluous.

Next comes the important commit statement. Without a commit all the changes you make and records you add will be lost when the database connection is closed. Note that if you wish to do several operations and not lose your original data, the rollback method can be used. The format would be as follows:

db.rollback()

Lastly we close our connection to the database with the close method.

Note that the commands executed are all standard SQL statements. For a primer on SQL statements install the MySQL package and run the MySQL Command Line Client. After you create a few tables and run a few queries you will be on your way.

Another great resource if it is installed on your SQL server is phpMyAdmin, The package is installed on some ISPs servers such as 1and1's Linux hosting packages. Using phpMyAdmin it is easy to build tables and populate them with data. After the tables are created there is an option to get the complete SQL statement to replicate the tables with the data which is handy if you need to send a copy of a test database to a friend without giving him access to your database server.

Setting up a Python CGI Sandbox on Windows

2011-02-21T14:13:00.000-08:00

It makes sense sometimes to set up a sandbox for development of CGI. By sandbox I mean a computer isolated from the web running all the programs needed to develop for CGI. If you have a Windows machine there are fewer resources available online for setting up Apache, etc than for a Linux box.

Note that installing a Apache server does take some resources but I noticed no difference on the 3 GHz Pentium D machine with 1 Gb RAM that I was using. follow these steps in setting up a windows machine:

Install Python
If you are going to put scripts on a server at an ISP such as 1and1 or GoDaddy you should be aware of the version of Python available to your hosting package. For 1and1 I installed Python 2.5. Also be aware that neither 1and1 nor GoDaddy use modpython at this time.
Install ApacheUse a standard install of Apache. It should take only a few minutes to install and configure. When you are setting up make it "localhost".
Add python as a CGI by modifying the following:
Options Indexes FollowSymLinks ExecCGI
AddHandler cgi-script .cgi .py
Install Eclipse or equivalent IDEEclipse is the best full featured IDE to use with Python. Although there is no standard build with Python as the default language, you can install the Java version of Eclipse and then install PyDev easily. Other good Python IDEs include Boa Constructor, Wing, or Idle.
Install MySQL (optional)Building scripts that access a MySQL database in Python is trivial in complexity but extremely useful and powerful. I would suggest installing MySQL even if you don't intend to use it immediately. The resources used are minimal.

There are some tips to getting Python working in CGI.
1. Always browse the pages through Apache.
Note that viewing files in the filesystem through a browser works for most things on an html page but will not work for CGI. For scripts to work they must be opened through the htdocs file system. The address line of your browser should look like:
\\127.0.0.1\index.html or
\\localhost\index.html

If you open a file up through the file system the CGI will not work.
c:\Apache\htdos\index.html

2. Convert end of lines of scripts to Unix format:
Most editors have options to "show end of lines" and then a checkbox to convert from Unix to PC format. you must have the end of lines set to Unix format.

3. State the path to the Python interpreter on the first line of the CGI script:
You must have one of the following lines as the first line of your Python CGI script:
   #!C:\Python25\Python.exe
   #!/usr/bin/python
The top line is used when you are debugging on a PC and the bottom is for a server such as 1and1. I leave the lines as shown and then edit them once they are up on the server by deleting the first line.

4. Print a content type specifying HTML before printing any other output:
This can be done simply by adding the following line somewhere very early in your script:
print "Content-Type: text/html\n\n"
Note that the 2 end of lines are required.

5. Setup Python scripts to give debugging information:
Import the following to get detailed debugging information.
import cgitb; cgitb.enable()
An alternative if cgitb is not available is to do the following:
import sys
sys.stderr = sys.stdout

6. On the server the python script permissions must be set to execute.
After uploading your files be sure to edit the first line and set the permissions for the file to execute.

A short debugging program for your CGI
(Remember most hosts DO NOT USE modpython)
This program will show what is entered on a form (both the keys and the values).

#!C:\Python25\Python.exe
#!/usr/bin/python

#4 things for python CGI
#Open file through the server not from filesystem
#file must be have linux end-of-line characters
#Must have the appropriate python line as first line of the file
#Print a "content-type" before any output

import cgi
import cgitb; cgitb.enable()
print "Content-Type: text/html\n\n"
form_data = cgi.FieldStorage()
print form_data.keys();
print form_data.values();
for name in form_data.keys():
   print "Key: " + name + " Value: " + form_data[name].value + "<BR>"

CamSoft System CS-209 - $1991.00

2011-02-19T19:33:00.000-08:00

When I bought my Bridgeport CNC Mill, it came with a CNC CS-209 control package made by CamSoft.

Here is a description from the CamSoft Website:

CNC Lite software, AS3000 3D CAD/CAM system, USB Jog Stick Handheld Controller, CS 14000 - 4 axes stepper motion board, cables with user provided computer.

CNC Lite Software

AS3000 Cad/Cam System

USB Jog Stick

Motion Boards

Limited time special offer starting at $1,991

I was excited about using this to retrofit the mill. Considering the kit had never been installed I thought that it should be pretty easy to get the mill up and running. The kit even comes with CAD software which is a big expense for CNC machining.

The CAD software is called Advanced System 3000 and requires a hardware key (I think). The software was on the computer that came with the mill but it was not very intuitive. I have used AutoCAD and Solidworks extensively so I was surprised that I could not really just start drawing.

The package also comes with CNC software. This software did not seem to be installed on the computer so I can not say anything about it. The manual is very complete but did not seem to have any information on how to install the system into a mill.

The package is supposed to come with a USB Game/Joystick which I did not get. The last owner said that his kids played with it and lost it. Seems to be the only part of the kit that was ever used.

The last piece of the package that I did receive was a small circuit board in a plastic enclosure that interfaces the computer to the milling machine. This package is for steppers so there are terminals for xyz step and direction.

There are also terminals for:

EStop

Lim

Pause

Home X, Y, Z, and A

MST ? not sure what most of these are

FID ?

CW and CCW ?

OUT ?
PWM ?

Needless to say there are a lot of terminals that need some documentation to hook up. At least the ESTOP is connected to ground with a jumper so I assume that when the connection is broken the card will enter an ESTOP condition.

I can estimate the parts on the board cost less than $40. Basically a processor, oscillator, 3 terminal blocks, a 7805 regulator, and a DB-9 plug for what I assume is a serial port. Not sure how a serial port would work for CNC unless the device is really an indexer that you send a command to serially. This is different than the idea of most CNC retrofit packages for stepper motors as they use the PC as the indexer and have a dumb opto-isolation interface/breakout board that connects to the parallel port.

So you might ask why I have nice pictures of the kit after my machine is retrofitted and running. Even before I got the Bridgeport in the garage I had called the company and requested some information on hooking up the kit.

Their response was to give me a $1000 quote for support. Even though the kit had never been installed and the only thing I needed was a hook-up diagram, they wanted to charge me $1000 to answer my question.

This got me so angry I put the kit back in the box and vowed never to use it.

I was thinking about this situation the other day and remembered my experience with Gecko. Since I also got 3 Gecko 201s with no paperwork I called that company for info and talked to Maris. He spent over an hour with me and helped me decide exactly how to use their drives and how to build a power supply for them. He even suggested that I get the first repair free if I burned one (as long as I was honest about what I did). Gecko drives cost less than $40 each ($120) when mine were bought but they still spent a long time helping me even though I was not the original purchaser. The CamSoft package cost more than 10X as much and they wanted 50% more to even talk to me.

You also might be curious as the what software and hardware I did use.

CNC Software : Enhanced Machine Controller - EMC2
Price : Free
Equivalent to CadSoft CNC lite which lists at $1995

Interface Board : CNC4PC C11G Breakout Board for Gecko Drives
Price : $109
Equivalent to CamSofts Step Motor Control Card - CS14000 which lists at $395

At the time there was no good free CAD/CAM software. I wrote a Python library to create G-Code. Maybe someday I will release it. However now there is a good free CAD/CAM software package.

CAD/CAM Software : HeeksCAD / HeeksCNC

Price : Free

Adequate option to CadSoft Advanced System 3000 which lists at $1295

Simple User Settings in a C# Windows Forms Application

2011-02-09T12:40:00.000-08:00

There is a lot of confusion and long programming blog posts on application settings for a Windows Forms Application in C#. I needed a quick and simple way to save a few user specific settings such as com port settings and names of labels on a customizable GUI.

I have used the Python config package written by Vinay Sajip in a previous project. The nice thing about the package was that it opened a config file and made an object which could be accessed as config.ports.baudrate. Since Python is not typed the config file, which is simply Python code without any punctuation marks, is flexible, fast and easy to create.

I had hoped that C# would have an easy way to build something similar. I found an post early on suggesting using app.config. After reading MANY posts on configuration and trying a lot of code that would not work on Visual Studio 2011 I had about given up and started writing my own.

Luckily I found a simple solution. A settings file is already included in a Windows Forms Application.

In the Solutions Explorer window expand Properties.
Double click the Settings.settings file and an editor will open.
Type the name of the setting, choose a type for the data, choose "Users Setting" in scope if you want the setting to be changed at run time, and enter a default value.
To access the variable in code use Properties.Settings.Default.yoursettingname.
To save new settings at run time use Properties.Settings.Default.Save which will create a new file. Note that when you change a setting the default value will not change in setting file editor.

Setting up Ubuntu for Automatic Turn-on in Emc2

2011-02-05T00:46:00.000-08:00

After booting Ubuntu, logging in, and starting up Emc2 for the past year, I am getting lazy. So I setup Ubuntu to automatically log in to my main account and start the EMC2 program. It is different than doing the same thing on Windows but possible (all thing that are possible in Windows are so in Linux usually with MANY more options...)

Setting up the computer to automatically log in to an account:
NOTE: This should probably not be done if the machine is on a network.

This one is simple and easy to find with a Google search:

Click on System -> Administration ->Login Window
Click on Security
The click on "Enable Automatic Login"
And select the name of your user in the box below it.

Setting up the machine to run a program like Windows "Start Menu"

My first thought was to modify the .login file which is the old school way to start programs outside of a windowing environment (back in 1987...)

With Ubuntu you have to start a program after the windowing environment has started. To do this you edit Sessions.

Click System -> Preferences -> Sessions
Click Add and enter a name and for the command enter something like
emc /home/username/emc2/configs/yourmachine/yourmachine.ini

Probably a good time to turn off a bunch of things that automatically start up that is not needed for a cnc machine (like the update which will break emc2).

C# Textbox - Enter to go to next control

2011-01-27T03:32:00.000-08:00

I was building a Windows Form Application in Visual C# Express 2010 and had a problem that needed a lot of searching to figure out. I could not get a value to "enter" and tab to the next textbox when I hit the Enter key.

After much trial and error (most of which would work but I still got a bell when I hit Enter) I found this.

Enter this as the KeyDown Event. Note that KeyPress uses KeyChar return types.

private void textbox1_KeyDown(object sender, KeyEventArgs e)
{
//checks for Enter, suppresses it and sends a tab
if (e.KeyCode == Keys.Enter && e.Modifiers == Keys.None)
    {
   e.SuppressKeyPress = true; //eliminates the enter key *BELL*
SendKeys.Send("{TAB}"); //changes focus to the next control
    }
}

DIY CNC Milling Machine Control Panel for EMC2

2010-03-29T20:37:00.000-07:00

This is meant to be an addition to a regular industrial style alphanumeric keyboard with trackball. It contains the most widely used functions as far as I now know. Since I am using a CNC4PC C11G I only have 5 inputs. All these functions are available on the keyboard within EMC2 and will not require a separate input. This panel will require a keyboard encoder either bought, ripped from an old keyboard, or made with a custom pcb. Keyboard encoders are available from Hagstrom, Ultimarc ($40) and Vetra.

Beyond Logic has all the information for rolling the code for your own keyboard controller which has some advantages. If you code your own then you can include functions for rotary switches (that include one-shots) and analog inputs.

This control panel is meant to be a cheap way of controlling the machine before or in conjunction with an MPG. This panel can be made for less than $200 which is a lot cheaper than an MPG.

One of the things this is missing is indicators/blinken lights. The power button is meant to be lit when on. Suggestions?

Machine Functions

Emergency Stop - with an added contact for drivers/vfd input
Machine On - Lit - with an added contact for machine functions/relay/contactor/etc
Coolant toggle
Spindle toggle (Turns the spindle on CW, could be more advanced as my Bridgeport has 2 speeds for Hi/Lo. But when do you need a button to control the spindle speed otherwise?)
Touch Off

Program Functions

Run
Stop
Feed Hold/Pause
Resume

Jog Functions

X increase / X decrease
Y increase / Y decrease
Z increase / Z decrease
A increase / A decrease
Jog Feed rate increase / decrease
Continuous Jog
Incremental Jog increase / decrease (first press selects incremental and second moves in 0.001,0.01,0.1)
Limits Override

Display Functions

DRO/Path Preview Toggle
Jog (Jog keys do not work in MDI so this button selects the jog page. MDI can be selected by the track ball or keyboard but will not have a button as it is a keyboard function)

Expansion

3 buttons without functions.

I would like to have a feed override but EMC2 does not have an easy buttons for this function. Instead EMC2 uses the number keys to select a percentage. I think that a potentiometer would be the most useful for feed override but that would require an analog input into the computer which I do not have.

For your reference here is the list of keyboard commands for EMC2 from the Axis Quick Reference help page.

Sparkfun Freeday - A Bust

2010-01-07T10:10:00.001-08:00

So many people on the net know about Sparkfun. It is a quirky website out of Boulder Colorado that sells electronic kits/gadgets/pcbs/components for building your own whatever. They concentrate on Ardunio type single board computers.

Today was "Freeday" where they gave away $100 to the first 1ooo customers. But before today they made a big deal about how they tuned up their servers to handle the load. Maybe they were a bit optimistic but MANY people who tried to participate (including myself) spent 2 hours hitting "refresh" when all we had to do was click "confirm order."

Now I (and many other people) have a huge level of frustration that because the site wouldn't let us through, we lost out. In other words the "free" offer was not played fairly because their servers slowed to a crawl. I would totally accept having the money go quickly (in something like 5 minutes) and I just missed out. But clicking refresh for 2 hours (literally) makes it unacceptable. Who are they anyway to waste 2 hours of my (and MANY other peoples) time?

So for "Freeday" Sparkfun got almost unlimited FREE advertising. Much more than $100,000 could have bought in traditional channels. They are #1 for google Search and twitter is "all a twitter" about Sparkfun.

But people all over the world got up early, or zoned out of work to click refresh for 2 hours. What was the real cost of Freeday in lost time and frustration? A quick estimate of 2 hours of $7.50 an hour for 100,000 people (probably many more) is 1.5 million. But I wonder what the statistics will show about how many people really tried to get in on Freeday. It may be better for Sparkfun if they don't publish the results.

Update: the site had 70,000 unique visitors that day. 70,000 * $15 = $1,050,000.

(Notice that they are no links in this message. Sparkfun got enough of my free advertising already)

Rotation Around a Point

2010-01-05T23:36:00.000-08:00

There are lots of code example that show rotation or a 2D point around the origin but what about around some arbitrary point? This is important if you are translating airfoils into G-Code...

To do a rotation around a point without matrix math you translate the point to rotate around the origin (0,0,0), then rotate the point, and translate it back.

So basically you subtract the location of the rotation point from the x coordinate, rotate the new point, and add the location of the rotation point back.

Here it is in Python

from math import *
def rotate2d(degrees,point,origin):
"""
A rotation function that rotates a point around a point
to rotate around the origin use [0,0]
"""
x = point[0] - origin[0]
yorz  = point[1] - origin[1]
newx = (x*cos(radians(degrees))) - (yorz*sin(radians(degrees)))
newyorz  = (x*sin(radians(degrees)))   (yorz*cos(radians(degrees)))
newx  = origin[0]
newyorz   = origin[1]

return newx,newyorz

Parabola in G code

2009-12-09T22:14:00.000-08:00

The following Python script produces a parabola in G-code.

#This code produces g-code for a parabola using the equation
#(y - k)2 = 4a(x - h). The parabola is open to positive x.
#a = x coor of focus
#k = x coor of back of parabola
#h = y coor of focus
#r = resolution
#ymax, ymax = limits of iteration
a = 2.0
k = 0.0
h = 0.0
ymax = 5.0
ymin = 0.0
resolution = 0.1
lastx = 0.0
lasty = h
def frange3(start, end=None, inc=None):
"""
A range function, that accepts float increments...
http://code.activestate.com/recipes/66472/
"""
import math

if end == None:
end = start + 0.0
start = 0.0
else: start += 0.0 # force it to be a float

if inc == None:
inc = 1.0
count = int(math.ceil((end - start) / inc))

L = [None,] * count

L[0] = start
for i in xrange(1,count):
L[i] = L[i-1] + inc
return L

#top half
for ystep in frange3(ymax+resolution,ymin,-resolution):
x = ( ((ystep - k)*(ystep - k)) + 4*a*h ) / (4*a)
print "G01 X"+str(x) +" Y"+str(ystep)#+"\n"
print "G01 X"+str(lastx) +" Y"+str(lasty)#+"\n"
#bottom half
for ystep in frange3(ymin,-(ymax+resolution),-resolution):
x = ( ((ystep - k)*(ystep - k)) + 4*a*h ) / (4*a)
print "G01 X"+str(x) +" Y"+str(ystep)#+"\n"

Repost: Summary of the Retrofit

2009-09-28T12:07:00.000-07:00

In a response to Where the heck? What the he11? HUNH? on CNCZone I posted the following. I realized later that it is a good summary of my retrofit so I will repost it here.

I am in the process of doing the same thing (a Bridgeport Boss CNC Retrofit). I have the gecko drives working, a Automation Direct GS2 VFD, and a power supply built with T1 (the 240 v to 120v transformer tapped at 40v). I already had Gecko 201s but the 203s would be better because of the auto short circuit protection circuitry.

Just remember that "common" on the Gecko 201s is 5 volts to power the opto-isolator LED. Also just wire 2 windings of 4 of the stepper motors because the windings are in bifilar (which means that 2 windings are wound together). There are jumpers on the motors that show which terminals are the ends of the windings and then wire to the other side. I have 1 sigma and 2 superior and the geckos work fine so far.

I used a C11G breakout board from CNC4PC which has some extras AC relays for coolant etc and is set up for direct wiring to a Gecko drive with opto isolators.

I am using the original limit switches and wired both NC and NO contacts for a separate e-stop and enable circuits. X and Y are set up as "both limits" in EMC2 and the Z has an upper, lower and a home switch. You can actually move the deceleration switch past the upper limit if you loosen the bracket screws and use it as upper limit. Then the screw adjustable switch can be a home switch.

All this fits in the back cabinet on the mill. Mine had no side cabinet.

For software I am using EMC2. It was probably the easiest part of the project. It has a nice wizard for setting up your mill which lets you check feed rates/limits/etc. They only problem that I had was a non compatible graphics card. Otherwise it was pretty straight forward to install on a empty HDD on a Dell GX240 computer (pent 4, 512 MB RAM, NVIDIA graphics card).

I got most of this information from this forum except for explicit directions on modifying the transformer which I just figured out after reading the suggestion on this forum.

I also had an hour long talk with Mariss at Gecko tech support who has probably forgotten more about Boss retrofits than I will ever know.

Basically my costs were:
Gecko drives - Free (came with the mill)
Stepper power supply parts
transformer - Free (came with mill)
bridge rectifier - 5$ at digikey
6800 uF capacitor - Free (I had one)
VFD from Automation Direct - $260 with shipping
C11G - ~$100 from CNC4PC
EMC2 - Free
Computer (GX240 MB on ebay $40 to put in old case I got surplus)

It is really not that big of a deal to do a retrofit using the original steppers once you get your head around it.

Angle Tight II Precision CNC Machine Vise at Enco

2009-09-26T11:56:00.000-07:00

I have frequently bought from Enco because their prices are much better than other places especially if you shop from the Enco flyer. Recently a machinists vise came up on sale. It is a presumably Chinese copy of a Kurt vise and seemed a good deal. However, while all the "good" vises such as Kurt or Parlec gave some kinds of specs for repeatability, flatness or parallelism the Angle Tight II ads listed nothing but holding force.

So I emailed Enco...

to EncoTechandParts@use-enco.com
date Thu, Sep 24, 2009 at 2:49 PM
subject Angle Tight II Precision CNC Machine Vise PN SU327-5893 Questions

I am interested in the Angle Tight II Precision CNC Machine Vise PN SU327-5893 that is on sale right now for $159.95.

I want to use it as an inexpensive CNC vise but there are no specs published in the flyer or the catalog.

What are the specs for accuracy, flatness or parallelism of the jaws? Is the bed ground to flatness?

Also, do Kurt style soft jaws fit the vise?

I am sure with some of this information on the ads the product would sell better.

Thanks,

Very quickly I did get a reply:

from Enco Parts
date
Thu, Sep 24, 2009 at 3:25 PM
subject
RE: Angle Tight II Precision CNC Machine Vise PN SU327-5893 Questions
Hello Gary

Unfortunately I do not have any specs on the vise you are looking at. We would have to measure the vise jaws and the kurt jaws to see if they will fit properly.

XXXXXXX XXXXXX
Enco Tech.
400 NV Pacific Hwy
Fernley, NV 89408
Ph. 800-873-3626 xXXXXXX
Fax 800-965-5857

Note that I have removed the person's name and extension.

This floored me. Enco Tech support doesn't have any information on their product? Why would there not be manuals or spec sheets sitting on the tech support person's desk describing what I think is a staple product for a machinist supply company?

Based on this I bought a Parlec off Ebay NIB even cheaper than what Enco had it for on sale.

But I felt I should communicate my dissatisfaction with the (non) Tech Support...

to Enco Parts
date Sat, Sep 26, 2009 at 12:51 PM
subject Re: Angle Tight II Precision CNC Machine Vise PN SU327-5893 Questions

Based on not having any specs and not getting my questions answered I bought a Parlec vise from another company.

This vise may be a good deal as many of your Chinese tools are. But for a vise which sets the precision of all parts made in it machinists have to know what the specs are. And you should know the dimensions of your products and have at least the manual to refer to. Maybe you will sell these to hobbyists but machinists need specs.

Based on this I would rate Enco low on customer service although I have bought from you in the past.

A lot of people complain about Enco in the web for both quality and service. Price wont last as a good selling tool. Service is very important especially when you are known for selling inexpensive foreign made equipment.

Thanks and just my 2 cents.

Have a good day.

Power Supply for CNC

2009-08-10T10:35:00.000-07:00

One of the first things that one needs to retrofit a Bridgeport Boss CNC machine is a power supply for the steppers. That is assuming that one has drives which I do in the form of Geckodrive G201s. The original Bridgeport power supply for the steppers put out 56 volts dc so most people use this voltage although some use 60 or even higher voltages. As far as current goes most people use 6-7 amps, 7 amps being the maximum that G201s will source.

While researching stepper power supplies I found a great reference on Gecko's website. http://www.geckodrive.com/upload/Step_motor_basics.pdf

This document not only shows how to wire the drives but gives a good example of a power supply with sample component values. Basically a power supply (unregulated) only needs a transformer putting out a desired voltage that is rectified by a full diode bridge and filtered by a big capacitor.

To get 56vac you need un-rectified 39vac. (56 v /1.414 = 39.6 v)

For a capacitor value C = (80000 uF x I) / V = 80000 uF x 5 amps / 56 volts = 7142 uF.
The closest standard value to 7100 is 6800.

For a bridge there are several high amperage bridges that are rated at a couple hundred volts. I found the MB352 made by Diodes Inc at Digikey that is rated 200 vac and 35 amps and only costs $4.50.

I designed a power supply using the suggested circuit but wanted some verification so I called Gecko tech support and had a very useful conversation with Mariss Freimanis from Geckodrive. After talking to Mariss I decided to run the motors at 56 volts and 6 amps. The motors are rated near/at 6 amps so giving myself 1 amp as a safety measure seems like a good idea.

It was suggested by Gecko that I first test my setup at 24v and about 5 amps. The drives are "hard to kill" at this voltage. After one maxes out the IPM at 24vdc the ratio of desired IPM is used to calculate the voltage needed compared to 24vdc. I will be happy with the IPM that I get at 56vdc which should be 150-180 IPM. I have decided to check out the drives and the motors at 24vdc first though however to get everything right.

It is suggested at CNCzone by a few people that one of the transformers (T1) in the control cabinet makes a great stepper power supply transformer. Also there are computer grade capacitors and a big heatsink in the computer cabinet that can be used. I did not have a computer cabinet so I had to provide my own.

T1 is a 240v transformer that provides 120v for the original setup. From the the CNCzone forum it is supposed to be rated at 1000va although I could not find this information on my own. The problem with T1 is that it does not have a tap at 39vac although a few people either rewind the secondary winding 0r cut a few windings out to make a 39 vac tap. The examples on CNCzone of this procedure have been with a 110vac input to the transformer.

It seems to me that using 120vac is not neccesery when you have 240 vac (which the machine needs to run anyway) already in the cabinet. The 240 is required if one is using a VFD to create the 208 three phase for the motor. Not having 3 phase in my shop this is a requirement for my installation. So with a single input of 240 vac I plan to run the VFD and T1 which will produce 120vac for the fans and the lube system (and coolant eventually) and 39vac for the stepper power supply.

According to the forum the secondary of T1 is 3 windings of 19 turns. So quickly I can estimate that 120vac/(3 x 19) turns or 120vac/57 turns or 2.10 vac / turn. So to get 39 vac 39vac / 2.10 vac/turn = 18.5 turns.

Hmmm... This is awful close to 1 winding. So if I put in a "tap" on the top of the second winding (or simply 19 turns away from X1) then I should get 39 vac. This is simple to test by plugging T1 into 240 and using a meter to look for a 39vac potential from X1 to one of the windings. By pressing (hard) the meter probe through the varnish on the winding you can find the magic spot and get the right voltage.

My test was a success but it was even easier than I thought. 39.6 vac (exactly) exists inside the core of the transformer but 40 vac (39.9) is on the top of the FIRST winding right below the terminals for X1 and X3. This is VERY simple. All I had to do was pull out the top winding and scrape off the varnish to solder on a new tap for the transformer. I made a new terminal from an extra contact from the 240 plug that I bought for the machine and connected it with a scrap of solid wire. The winding seemed to be 10awg which should handle the current just fine.

(Note that the schematics from Bridgeport show T1 as having multiple taps so there are probably multiple flavors of T1 and some may not be as easy to modify.)

Tooling and Retrofit Status

2009-07-21T12:32:00.000-07:00

Before I go much further I should note that I am new to CNC and machining in general. Which means I have no tooling. I do have a good set of import drills and a set of inexpensive end mills but no test indicator, to tool holders, etc.

One of the first things I looked at when I got the machine was the taper. These machines came with 2 types of Quick Connect tapers, either QC#30 or Kwik Switch 200. My machine has Kwik Switch 200 which according to users of CNCZone is far superior to R8. Unfortunately tool holders are not as common as R8 or as inexpensive.

The first tool holding device I acquired (or am acquiring) is a keyless chuck and a 1JT Kwik Connect 200 adapter.

This is what the one that I won in auction looks like. Although I did win the auction a while back, I have still not received the adapter. I first bought a 1JT adapter but plan on getting a 2JT and 3JT adapters. I also bought a 5/15" keyless chuck for the 1JT and will get a 3/8" for a 2JT but for the 3JT I will get a Jacobs 14N as they come highly reviewed.

I would also like to have some collet holders and collet sets. The machine came with 2 Universal collet holders with 3/4" collets. This disappointed me some to have such a big size collet until I learned that many types of tooling come with a 3/4" shank such as fly cutters. There are quite a few sets on Ebay with 3/4" shanks fairly cheap (<$40). But one of the first things I did when I got the machine was research collets sets. For Kwik Switch 200 there are 2 collet types that are available commonly. Universal had a Double Taper type that is the same as the tooling that came with the machine. Then there is a Acura-Flex type that is also common. Actually there are a few Acura collet types (Acura-Flex, Acura-Mill, Acura-Grip, and Acura-Tap) but the flex seems to be the most common. Shortly after I bought the machine 3 complete sets of collets came available on Ebay. Two sets of 3/8" collets and a set of 3/4" collets. I was able to win all three. I immediately bought the 2 available Kwik Connect 200 3/8" collet holders off Tools and Gizmos.

Since I will be working in small tool sizes at first I put off buying the 3/4" tool holders as they seem more common anyway. I will buy another couple 3/8" collet chucks when they are available. The pic below is the 3/4" collet set. The owner claims to have used the 3/4" collet only once and lists the set as "New".

The 3/8" sets are also still in the "box" but have had use.

Next stop will be a purchase at Enco for assorted items and some Vactra #2 Way Lube which is on sale. One thing that I am purchasing are Mason Neoprene Mounts in the 500-1000 lb range. I am unsure how to get the machine off the floor to install them however. I have seen some nice mobile bases at Grizzly but nothing that would do 2600lbs. It would be nice to have a base with casters that could be moved around in the garage.

I am looking at the Automation Direct GS2 Variable Frequency Drive for the spindle motor. It is well documented at least and can be purchased new. Also, the installation manual for EMC2 lists a driver for the device. A 2hp GS2 lists for $241.

I tried EMC2 in the computer that came with the machine. With only 256Mb of memory and a 800 MHz Duron the computer scored >5,000,000 in latency in the EMC2 test so it looks like I need to find a bit faster machine to use for CNC control.

Software Options

2009-07-17T07:44:00.000-07:00

CNC Software is something that I have researched for many years. I actually have a set of three stepper drivers, a couple good NEMA 23 motors and a small XY table that I bought from Grizzly. What was always missing was the software (both CNC and CAD/CAM). Over the last few years I have searched and collected demos and free software.

The best option for free software for CNC control is EMC2. http://www.linuxcnc.org/
Although the software runs on Linux it is a very good option for CNC work.

The Bridgeport actually came with software and a computer running Win 98. The software is made by CamSoft and is both a CNC control package and a CAD/CAM package.

A while back I downloaded a CAM program demo from MecSoft called VisualMill. I have not yet installed it but will try it out. My interest in VisualMill was because of a plug in for Rhino. A friend's husband uses Rhino to design hulls of hydrofoil assisted catamarans, very cool technology. He suggested that he program is a good value to it's capabilities.

EMC2
To try out EMC2 it is as simple as downloading a live CD and burning it to a disk. A live CD is a bootable disc that you can run on your computer without changing your operating system or loading anything onto your hard drive for that matter. You simply install the CD in your drive, shutdown and reboot the computer, and the software will load (as long as you allow booting from CD in your BIOS settings). After you are done evaluating the software, you remove the live CD and reboot the machine. There are no changes whatsoever to your machine or operating system.

The EMC2 live CD works well. It is based on Ubuntu 8.04 which is a capable and recent distro of Linux. It is not the most recent version but will be supported for at least 3 years which is why the EMC2 team selected it.

After EMC2 has booted you get a standard Ubuntu desktop. Select Applications, then Linux CAM and then the EMC setup utility. You select the the machine you have and then setup parallel port settings. Even though there is no CNC machine connected to the computer the software will run. (If you are playing with the port setup and specify limit switches the software may not run because it is looking for certain inputs on the port which will not be present.) The software seems simple enough and the setup shows just how trivial setting up a parallel port stepper motor CNC machine can be.

CamSoft
When I took inventory of the software that came with the machine I found 2 cds, 2 floppy discs, a hardware key (dongle), 2 large manuals, and a card in a black enclosure that has labels for limit switches and stepper motors. The software is older versions of CNCLite for CNC Control and AS4000 for CAD/CAM. The card turned out to be a Step Motor Control Card model CS14000. I also found a receipt that listed the total cost for the software packages, card and a controller (PS2 type joystick) for $1991 in the system CS-209 package.

From the website:

CNC Lite software, AS3000 3D CAD/CAM system, USB Jog Stick Handheld Controller, CS 14000 - 4 axes stepper motion board, cables with user provided computer.

Limited time special offer starting at $1,991

A big part of what I noticed that I am missing is the installation/integration manual so I called the company. Actually when I registered to for a chance for a free software package contest I received a cold call from the company so actually I was returning a phone call. I talked to Gary in sales who told me that to get technical support and upgrades to the software I should buy a maintenance package which could cost from 0$ to 1000$. Otherwise it seems that I can not get technical support or help installing the software which was old enough that even his techs would have a hard time installing.

This made me curious so I tried installing the CNC Lite software. When the CD boots I get a big menu of operating systems from Win95 to Win XP. I chose 98 and went through the process as much as I could figure out. There is a second screen and 5 or 6 options but the only one that would work is the 1 - Install Graphical Interface option. After installing the software and trying to run it I got a password screen but have no idea of what the password is. I will try to call the company and try to find a forum for installation help.

I have decided that I will definitely try to get the CamSoft software installed and post a record of that process here.

Maintenance of a 30 Year Old CNC Milling Machine

2009-07-08T16:17:00.000-07:00

One of the big questions that I have about the new milling machine is maintenance and cleaning.

Cleaning the ways
I was almost tempted to get out the Foamy Engine Clean and spray down the machine and let all the sludge drip onto the floor. However I avoided cleaning anything that may contain grease or lube with any degreaser. On the painted surfaces I used a version of "Orange Clean" (which I could not find locally). It is called "Greased Lightning Blast" with orange oil. It made short work of most of the grease on the machine grey paint.

The machine after a bit of cleaning. Anyone have a source for cans of enamel spray paint that matches?

Way Wipers
A quick Google search shows that many people want to sell you exotic and probably expensive way wipers. But on Ebay a couple sellers offer felt way wipers specially for Series 1 Bridgeport. I still haven't decided what to do about the wipers. It is suggested that they are changed out yearly so I am guessing I need to replace them before running the machine. I will probably pull mine out and see if they can be cleaned and lubed for now.

Way Lube
The automatic lubrication system reservoir had some liquid oil in it but also had a sludge at the bottom. I removed the tank and cleaned the whole assembly. The maintenance manual suggests Sunoco Waylube 80 (or equivalent) for the automatic lube system. This is a bit hard to find. But http://www.metalwebnews.com/howto/chart/lube.html actually is a chart of way oil equivalents. In this list is suggests that ISO VG 68 is a replacement. Enco lists a Hangsterfer's ISO VG 68 Way Oil for $24 a gallon (#319-3925).

OK, recently found page 2-5 which lists MANY approved way lubes. Some notables:
Mobile Vactra Oil No. 2 (available at Grainger in 5 gallon pails for $100)

Another link with equivalent way oils: http://www.idahomachinery.com/PDFFiles/MachineLubricantCrossReference.pdf. I guess everything crosses to Hangsterfer's.

Other Oiling
There is a nice plaque on the head with suggested oiling procedures. I need to find the oiling points and a source for appropriate oil. More Later...

Belt Drives
There are timing belts on each of the axis and a belt in the head to change speeds (I think). I will need to inspect these belts and find a replacement source. Also it may be that a newer type material may be quieter/faster.

Other Machining Information
I actually found some good introductory videos on the MIT Tech TV website. The videos are for training students in building prototypes in the MIT robotics lab. The milling machine videos start at #4 http://techtv.mit.edu/videos/127-machine-shop-4.

New Project - Bridgeport Boss CNC Retrofit

2009-07-07T08:19:00.000-07:00

I have a new project. Recently a series 1 Bridgeport BOSS CNC milling machine was posted on Craigslist. The machine was in the process of being retrofitted as the control went down and a previous owner threw it away. It came with a couple tool holders, some Gecko stepper drivers, some software packages and all the manuals. I contacted the seller to ask about its availability. It was available so after a discussion with the fiancee I made arrangements to go inspect the machine.

In the meantime I learned a little about Bridgeport BOSS CNC milling machines. Basically they are similar to manual Bridgeport milling machines but have ball screws and big stepper motors that drive the screws on the X, Y, and Z axis. They do not run manually. Also they have pretty obsolete controls that were quite capable for their time. The stock controls have a resolution of 0.001 and have 200 step per revolution motors with 1:1 pulleys. But basically they are VERY capable machines when retrofitted and a similar ball screw CNC mill with that rigidity and capability is not available for less than $7000. They are also reported to be fairly easy to retrofit.

So YES, we decided to get it. I drove up to the seller's residence and viewed the machine. under a coat of old grease was a machine with little apparent wear. The grease was dry and sticky though and would need to be removed. The motor data plate showed that it was 3 phase 208. I knew that with a phase converter you can make 3 phase out of 2 phase.

The seller was pretty knowledgeable about machines and had a CNC machining center that he uses to make decorative western belt buckles and "real" spurs. He didn't have time for the retrofit and had a full shop already. In the Craigslist ad he listed that he could deliver the mill.

I paid him for the machine and arranged delivery. He had a trailer and could load the machine and I would get rent a skid steer to unload the machine. I briefly had looked at using a tilt trailer and rollers to move the machine but after talking to a local machinist, Tony at Knick's Machine, decided that lifting it would be easier. Since the seller had moved machines before, I trusted him to be knowledgeable about moving the machine.

The next step for me was to make space in the garage. This is where an able and supportive fiancee really helps. It took us only 12 hours to get the garage all moved and arranged and about 5 cubic yards of garage sale stuff out on the porch. I gave the machine an open area 9'x10' since I would be working on the machine. Also this machine only has one control cabinet on the back and is missing the tape drive box.

The seller brought the machine down to Bozeman on a big flatbed trailer. He tied it down with chains and a nylon lifting strap. He used the knee to tighten up the nylon strap (later I found that the one Y limit switch stop was bent slightly). I rented a skid steer (Bobcat) with pallet forks to lift the mill off the trailer. When the seller and I went to pick it up he noted that the Bobcat probably wasn't rated to lift the mill. We changed the rental to a fork lift with 4 wheel steering which had 5000 lbs rating. The price for a 2 hour fork lift rental, a trailer, and a gallon of fuel was less than $100.

We got the machine off the trailer and into the garage with no mishaps. By lowering the mill almost to the floor we were able to get the fork lift into the garage. Once the mill was down we were able to spin it slightly to get it straight. The machine has no leveling feet so it will spin if two people push hard enough.

to		EncoTechandParts@use-enco.com
date		Thu, Sep 24, 2009 at 2:49 PM
subject		Angle Tight II Precision CNC Machine Vise PN SU327-5893 Questions

from	Enco Parts
date		Thu, Sep 24, 2009 at 3:25 PM
subject		RE: Angle Tight II Precision CNC Machine Vise PN SU327-5893 Questions

to		Enco Parts
date		Sat, Sep 26, 2009 at 12:51 PM
subject		Re: Angle Tight II Precision CNC Machine Vise PN SU327-5893 Questions