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Author Topic: Bridgeport Romi lathe retrofit with csmio ipa  (Read 4939 times)

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Bridgeport Romi lathe retrofit with csmio ipa
« on: February 27, 2017, 03:39:00 PM »
Toying with retrofitting a Romi lathe with a csmio ipa,threading module and handwheel, and using the existing hardware. Totally new to this,but have seen a similar build on here. No doubt I will ask numerous,seemingly stupid questions, but please bare with me
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #1 on: March 04, 2017, 11:34:31 PM »
Hi Johnny,

I don't have any experience with lathe retro-fitting but I can help with some general information based on my IP/A mill retrofit:

I'm using windows 7 (32 bit version) and my PC is NOT connected to the internet. Like you I was fearful of the "automatic updates". Mach 3 is running fine on this config. All gcode gets to the mill via a USB thumb drive. Admittedly old school but I like that my mill is safe from all the internet distributed virus and malware crap.

As for running the lathe with a VFD....I run my manual lathe (Southbend 16 x 6) with a VFD because it's 3-phase and I don't have 3-phase in my home shop. Threading is not an issue since the lead screw or cross feed still runs at a fixed fraction of the spindle irregardless of motor RPM. The head on my lathe is belt drive so I'm a big fan of using the VFD to get the spindle speed I want. I find I run on the middle pulley and I almost never use the back-gear. My work is usually 6061 or A36 and I'm not ever trying to mass produce anything...

As for your particular retro-fit... I'd encourage you to go for it if you have a known good lathe (minimal backlash) with an antiquated CNC control. You should verify that your servos, encoders and servo amps are in good working order before proceeding with the IP/A. If you find you need to update your servo amps this this may lead you down a path towards going step/dir rather than analog... Also, encoders should be 500line or better.

Hope this helps!
Mike




Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #2 on: March 05, 2017, 12:36:59 AM »
Thanks for your reply Mike.  Still in the process of trying to get it fired up with the old controls to ascertain whether or not the servos and drives are any good. Unfortunately,this machine hails back to the advent of the Elf and Safe Tea movement in the Uk. Had to have all the safety relays etc fitted by Bridgeport before they could sell it in the Uk market. There are very few around,and information is minimal.  It's got an overly complex arrangements of guards and interlocks on it,so that,coupled to a very poor copy of a wiring diagram,is really hampering my efforts at the moment . Chaosengineering,on here,is also doing a csmio ipa retrofit,and, he has said he has a wiring diagram.

Found out yesterday the bridge rectifier in the 24v psu is blown. Have fitted a 500w 24v psu temporarily. Seem to be getting closer to getting it running.  On the subject of running the bed,slideways etc seem to be in excellent condition. That,coupled to the paint on the bed directly underneath the chuck hardly been worn off,,leads me to believe it's seen little use.  A previous owner has obviously spent a fair amount on boards and harnesses. Think this might have been plagued by electrical gremlins from the outset.Having done a fair amount of internet research,i still have to find a single thread where someone hasn't had an electrical problem.

I think it is an ideal candidate for a retrofit,has ballspindles etc already fitted.  Would like to fit a vfd to it, not to run it on single phase,but to be able to control the spindle speed and hopefully get constant cutting speed set up.

How user friendly did you find the whole csmio ipa wiring up and configure when you did your mill, Mike?  I haven't any experience with anything like this. No formal electronics or electrical training,but can find my way around a wiring diagram and can do basic fault finding.

Thanks again
Johnny
« Last Edit: March 05, 2017, 12:38:51 AM by Johnny Bravo »
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #3 on: March 06, 2017, 12:25:18 AM »
I found the csmio-ip/a docs to be quite good. You need a basic understanding of how a closed loop servo control system works. You will need electrical schematics for your machine that show servo, encoder and servo amp wiring. Lastly, you will need a VOM to do basic continuity testing along with perhaps taking voltage measurements. Sounds to me like you have the skills necessary to complete the retrofit....

As for running the lathe with a VFD... I don't see why it shouldn't work. The spindle will have an encoder/tachometer that tells the control how fast it's turning. The control should care less about how the spindle gets to that RPM.

Hopefully Hood will chime in here. I think he's done a lathe retrofit with the CSMIO-IP/A control.

Good luck!
Mike


Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #4 on: March 06, 2017, 01:31:13 AM »
Thanks Mike

I have a decent Fluke digital multimeter. Have a wiring diagram and have sussed out pretty much what would need to stay and what's redundant.  Whilst the wiring diagram isn't the greatest, it's a copy of a folded original, at least the fold isn't through the bit I would need to keep
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #5 on: March 06, 2017, 11:43:18 PM »
Good luck Johnny, Sounds like a fun project. Let us know how it goes... I can't find the " Chaosengineerings build thread" that you mention?

Mike
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #6 on: March 07, 2017, 12:06:23 AM »
Will do. Thanks Mike .

Chaosengineering' s build thread is in "The General Mach Discussion", section,under the heading of ,"Novice to Mach3,may be asking too much??"
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #7 on: March 11, 2017, 01:04:28 AM »
Last ditch attempt this weekend to see if I can get this up and running with its original controller. Being based in the Uk, these Bridgeport Romi lathes are few and far between,, and parts availability pretty much zero. I am loathe to spend any money on spares for it from the states, given its reputation for being plagued with electrical gremlins from the start.  So, its decisions time.

It's basically a low mileage 16,5x40" engine lathe,fitted with ballscrews anda pc based controller from Bridgeport.140v dc servo motors,the one on the x axis showing signs of being rebuilt at some point,( rebuilding company's sticker embedded in a thick coat of paint).  Given it's unreliable status,and showing signs that the previous owner had thrown a fair amount of money at it,coupled to me not being able to test if the servo drivers and servo boards are any good,makes me think he best way forward would be to rip it all out and start again. Financially ,at this point,it would make sense to use a controller that would drive these existing servos,hence my thinking of using a csmio IPA.  If it turns out that the servo or drivers are shot, I need a cost effective solution.  I do like the look of the ac servos,they would make fir a very clean and tidy installation.Here in lies the problem...

Being totally new to this and having never done anything like this,how do I size the ac servos? I want to use servos,not stepper motors. These most likely will be sourced from China.Having read up a bit,there are calculators out there, but not knowing the weight of the saddle ,etc, they seem pretty useless
« Last Edit: March 11, 2017, 01:07:56 AM by Johnny Bravo »
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #8 on: March 11, 2017, 10:41:06 PM »
Hey Johnny,

Mike here again... Have you seen this thread from CNCZone: http://www.cnczone.com/forums/bridgeport-romi-lathes/289634-cnc.html

If I were in your shoes I'd at least try and use the DC Servos that came with the machine. My thinking is that if Bridgport/romi did a good job engineering the machine then the servos should be well matched to the machine. As per the post above, the Gecko drives are reasonably priced. If you go Gecko you'd want to go with the IP-S step/dir.

Mike
 
Re: Bridgeport Romi lathe retrofit with csmio ipa
« Reply #9 on: March 11, 2017, 11:27:35 PM »
Hi Mike. No,I hadn't seen that,will look now
« Last Edit: March 11, 2017, 11:44:28 PM by Johnny Bravo »