Build Thread- Bridgeport Boss 3 upgrade

[HawkJET]

I don't know that I'm technically a newbie, I have been automating machinery for years. But I have not used Linux at all and have only recently become interested in EMC2.

I have a Bridgeport Boss 3 Series I mill. I have read the articles in Home Shop Machinist that go through the steps of removing the old controls and preparing the machine for new electronics. I am at the stage where I am cleaning all the goo and grime from the machine.

I have Compumotor Zeta Stepper Motor drivers and have 'exercised' the axes using a single axis indexer. This way I have confirmed that I know how to wire the motors and they work.

A computer has been ordered and should be here in about a week.

I am wondering about a Break Out Board and how much 'extra' controls I can get. If this works well, I have another application that will need as many as six or eight relays (or equivalent) controlled with M codes.

I have seen the ModIO products at Homann Designs and I am confused as to what ModIO is and how it is connected to the computer.

Can someone give me a primer on controlling I/O with EMC2, BOBs, etc?

Oh, and a little background on me... I am a mechanical engineer, mold maker, owner of a small machine shop and sometimes an electronics technician. I understand stepper motors well (I used to design and build them when I worked for Compumotor about 30 years ago). I am fairly well versed in things computer (Windoze though) and am just ignorant in the realm of Linux, EMC2 and I/O control.

I appreciate any help you may have!

[kanton]

HawkJET.

Which issues of Home Shop Machinist have the articles that you referred to?

Thanks.

[HawkJET]

Originally Posted by kanton Which issues of Home Shop Machinist have the articles that you referred to?

HSM Sep - Oct 2004
HSM Nov - Dec 2004
HSM Jan - Feb 2004

You can get pdf copies of them at:

http://www.mgertech.com/cnc/cncmachining.htm

Under "-BRIDGEPORT CNC RECLAIM"

[samco]

Hello. Don't be afraid!

Depends on what you are looking at doing.. Are you planning on just using a printer port? Or 2 or 4? There are many ready made Bobs that work great with emc. (I don't know of any as I make my own when needed) You will be limited by step speed and such. Do you know what step frequency you are going to require? Most computers running emc can do anywhere from 20-40khz+.

there are also quite a few inexpensive interfaces that give you a lot more abillity - like Pico, mesa and such. They move the step generation/ encoder counting to the hardware so emc's load is reduced.

http://wiki.linuxcnc.org/cgi-bin/emc...orted_Hardware

(both mesa and pico are very involved in emc)

Also - as far as modbus - emc seems to support it through the classic ladder interface - but I have not played with it.
http://www.linuxcnc.org/docs/2.3/htm...der.html#r1_10

Classic ladder is integrated within emc allowing you to do ladder logic also.
http://www.linuxcnc.org/docs/2.3/htm...ic_ladder.html

read read read
http://www.linuxcnc.org/docs/2.3/html/

Are you planning also to be able to rigid tap?

sam

[HawkJET]

Originally Posted by samco Are you planning on just using a printer port? Or 2 or 4?

Probably two at the most. I don't know what is available from just one.

Originally Posted by samco There are many ready made Bobs that work great with emc. (I don't know of any as I make my own when needed)

I'm interested in what you have done. Do you have any build threads for building BOBs? Do you opto isolate? Buffer? Use relays? I'm interested in what you have done.

Originally Posted by samco You will be limited by step speed and such. Do you know what step frequency you are going to require? Most computers running emc can do anywhere from 20-40khz+.

I haven't yet experimented with step resolution so I don't know for sure. I suspect 20-40khz should do it.

Originally Posted by samco there are also quite a few inexpensive interfaces that give you a lot more abillity - like Pico, mesa and such. They move the step generation/ encoder counting to the hardware so emc's load is reduced.

I quickly glanced at one of these. They look very cool! I'll be looking into it further.

Originally Posted by samco Are you planning also to be able to rigid tap?

No.

[BobWarfield]

Here is an introduction to Breakout Boards:

http://www.cnccookbook.com/CCBreakoutBoards.htm

The main reason to use a ModIO is the limit on the number of I/O lines available with a parallel port. If you can get by with what's available, you won't need one. You can also use a 2nd parallel port to increase the number of lines.

Alternatively, you could use a motion controller, like a Smoothstepper. Not familiar with what EMC supports or doesn't there.

Cheers,

BW

[HawkJET]

Originally Posted by BobWarfield The main reason to use a ModIO is the limit on the number of I/O lines available with a parallel port. If you can get by with what's available, you won't need one. You can also use a 2nd parallel port to increase the number of lines.

This is basically what I had assumed. I guess I don't have the 'big picture' with I/O in general. What do people generally use? Does a control console with keypad and various control switches take the I/O from the parallel port? Does a second parallel port add a significant amount of capability? Is a second parallel port easy to get? (it has been years since I had to deal with printer port cards and parallel has given way to USB....)

Originally Posted by BobWarfield Alternatively, you could use a motion controller, like a Smoothstepper. Not familiar with what EMC supports or doesn't there.

I understand Mach3 is the only software to support SS.

[BobWarfield]

The real bottleneck is inputs. With parallel, you generally get 11 outputs and 5 inputs. You can go through those inputs in a hurry by the time you've got home/limit switches and now want a bunch of control panel functions.

Another approach is to use a key simulator. This is a little box you can plug between your keyboard and your control panel. It adds a bunch of inputs. You close and input and it sends a keycode as though you had typed it on the keyboard. So, for example, you could use a game controller joystick to simulate pressing the arrow keys to jog.

This works pretty well, so long as the key pulses don't come to close together. You could do a lot of pushbuttons on a panel that way, for example.

So your choices would be one or more of:

- Add an additional parallel port card, pick up 11 outputs and 5 more inputs. I'd probably only do this if I wanted to run my MPG this way.

- Add a key emulator. Probably the cheapest and easiest way to get a bunch of buttons going on a panel.

- Use a touch screen. That works great for buttons too!

- Use a ModIO. BTW, Homann makes a real cool pendant that works via ModIO that I am building for my mill.

- Use a motion controller that has a lot of inputs like a Smoothstepper.

The input problem is what got me to buy an original GRex. It's a nuisance. These days I am inclined to go with a touch panel and a ModIO-based pendant with an MPG. Easy to set up and lots of bang for the buck.

Cheers,

BW

[HawkJET]

Originally Posted by BobWarfield So your choices would be one or more of: - Add an additional parallel port card, pick up 11 outputs and 5 more inputs. I'd probably only do this if I wanted to run my MPG this way.

I may do this too.

- Add a key emulator. Probably the cheapest and easiest way to get a bunch of buttons going on a panel.

This looks like the way to go.

- Use a touch screen. That works great for buttons too!

This could be really cool also.

- Use a ModIO. BTW, Homann makes a real cool pendant that works via ModIO that I am building for my mill.

This would be my second choice - only if I can't get the I/O I need from other methods.

- Use a motion controller that has a lot of inputs like a Smoothstepper.

Since SmoothStepper isn't supported by EMC2, I found this from one of the links in samco's post (above):
http://pico-systems.com/univstep.html

It looks like it is similar to SS, but for EMC2.

[HawkJET]

Does anybody have experience with Pico Systems Universal Stepper Controller?

[jmelson]

Originally Posted by HawkJET Does anybody have experience with Pico Systems Universal Stepper Controller?

You will find a lot more users on the EMC-users group on sourceforge than here. (see
emc-users@lists.sourceforge.net ) I've sold 99 of them so far, so it is a bit of a niche product, but has been on the market since 2002, so it was the first external step generator for EMC (back before there WAS an EMC2.)

Jon

[HawkJET]

Enough of my questions have been answered that I got enough background to understand what I have been finding from web searches. Thanks to all.

I am now planning on making my own BreakOut Board. Although I know just enough electronics to be dangerous, this is a fairly simple task for my electronics skills. I'll post the progress.