Advice on Hardinge CHNC retrofit

[rkdygert]

My CHNC is on it's last leg with its AB 7370 controller and I am looking to retrofit it. Almost everything I am reading here indicates that any of the commercially available retro kits are crappy so I am looking to build my own PC-based controller. I am thinking about using Gecko drives with Mach software. My concern is that the motion of the axis will not be fluid enough due to the step pulse output of the software. Is this a valid concern and if so, what other options do I have?

Also, does anyone know if the Mach software can handle the automatic turret on the lathe?

Any advice/info is appreciated. Thanks.
-Ryan

[DennisCNC]

Take a look here there are a few people that are working on CHNC's:
http://www.machsupport.com/forum/ind...267&board=27.0

[Drew]

If you can go with digital servo the motion should be smooth.
It will show up most when changing direction of the tool path.
My hnc ran with AH-HA soft/hardware and did all of the original functions.
I changed to stepper motors but servos would be better.
I'm changing to M3 touchscreen with grex right now.To index the turret you first fire the relay to index turret then read 4 inputs combine them to a binary number from 1(0001) to 8(1000). When they match the desired tool fire the turret stop/lock relay then release the index relay. Next check that the turret is down(wait for sensor output) and release the stop/lock relay.Ypu may need to adjust the turret encoder for timing.

[jmullett]

I redid a 2-axis toolroom lathe with a bad Anilam controller. I had success using Rutex 991H, step and direction to +/- 10 Volt, controllers feeding my existing servo drives. It was much cheaper then purchasing new drives since my Westamps were still performing well. Rutex is still in business and are going through some chip changes right now but they might still have some of the 991H or equivalents in stock. Maybe someone else makes a competing product, anyone?

Mach3Turn had enough user configurability for me to get the multipass threading to work. And my spindle control is about there through mod-bus communications. I don't trust my pneumatic turret enough not to put in a M00 to verify tool change.

Mach is the best open loop (closed within the drive only) PC control option I've run into. Probably one tenth of the hardware cost of the next closest closed loop pc lathe option that I am aware of (www.mdsi2.com). I don't think EMC could be considered right for lathe at this time.

[Karl_T]

I've just recently finished refitting a CHNC with Camsoft. The machine is better than new. But Camsoft is an expensive control - may be more than you'd like to spend.

Just my opinion, but using a keyboard to contol a commercial CNC machine sux. I installed all the control buttons and dials you'd see on any recent name brand control. This resulted in 50 inputs and 20 outputs. Way more than you can do with Mach.

Karl


Karl

[DennisCNC]

jmullett,

Here is a similar product and there is af few people runing them on the forum:
http://www.skyko.com/products/



If you need a lot of I/O's you can get a PLC to talk to Mach over ModIO:
http://www.machsupport.com/forum/index.php?board=35.0

[Drew]

Hey Karl how about a picture of that control.

[Karl_T]

Originally Posted by Drew Hey Karl how about a picture of that control.

Sorry, I'm about 2000 miles from it right now. I'll try to remember when I get home.

Karl

[Barker806]

Karl,
We can do 100+ I/O on any number of things... We are working on Galil (that can have 64 points) and you could add a PLC (over modbus). This could get you more IO then you could ever need I am with you and I HATE the KB! Every machine that I do has a Nema 4 touch screen, knobs and buttons! I use a PLC because it is only 200.00 for one and I don't need to get all the opto 22 stuff. I love the opto 22's but they add up fast!

Just wanted to tell you that it is not all about the printer port any more We are just about to start Delta Tau as well.. Man they have nice stuff!

Thanks
Brian

[Karl_T]

Brian, I continue to be amazed at how fast the MachX software continues to be advanced...

I remember all to well problems coordinating Modicon PLCs over Modbus with GM-Fanuc robots...( I was an engineer on a 50 machine molding and packing line)

For example, with all the I/O in the host its a trivial thing to have a Jog swtich move an axis unless a limit switch is hit. With Mach, the axis move and the limit switch will be in the Mach software and the Jog input will be in the PLC. Do this for four directions, add a switch for jog speed, and then a handwheel for fine jog control and you can have a real mess.

Here's hoping you come up with an elegant and simple solution to this problem.

Karl

[Barker806]

Modbus is not the best but it is good for IO that is not super high speed... We are looking into Ethernet Powerlink, I think you will be happy with the timing of that

[Drew]

Will Mach3 send commands through RS-232 to RS 485 converter board then to a OPTO 22 B100 brain on a 16 point rack? And can it recive a reply back from B100? And is there a limit to the number of input or output modules that can be on the rack other than a total of 16? (like 12in 4out or 5in 11out) Thanks Drew