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Author Topic: New maching- Converting HM48 to CNC with mach3 or mach4?  (Read 2028 times)

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New maching- Converting HM48 to CNC with mach3 or mach4?
« on: July 21, 2016, 03:27:19 AM »
Hey all.
I bought a HM48 which is the largest machine that fits under my house,
next step- CNC conversion.

I want to run the standard motor at the moment, but have high hopes of rigid tapping and VFD controlled spindle- maybe I should go the whole hog first up?

My question is (Hoping HOOD can throw in his two cents too... I'll put the questions in number format for easy helping...

1: I am really familiar with Mach 3, but how far along is Mach4 now? With mach 3 I can even do probing and indexing hex stock on a 4th axis, how are the plugins coming along? I would like to use it as its so fast at doing things in comparison but I have so much invested in M3

2: Buy individual motors/power supplies/ drivers etc or get a kit off ebay/alibaba for about 1000 bucks for 1400oz+ steppers?

3:  Controller - I like the idea of CSMIO/KFLOP but never used them, for things like rigid tapping and indexing boring operations would I need this with a servo motor as a spindle and run it as an A axis etc? I have heard you can get servo motors with Step/Dir but how to achieve this will be mind**** without some serious help. -> Lookin at you Hood! I am happy to interpolate the threads with a thread cutter, but the machine is a gear head and I'll convert it to belt drive so I can run 6000rpm. Should I just do that and run with a CNC4PC controller or go the CSMIO

4: Ballscrews... 20mm is cheap, 25+ are crazy expensive. 20mm work ok?

5: This is the first time I'll be wiring this up from scratch, and I do have in my mind that I hated the homing and home switches on my last machine always being out. If I turned the machine off, re-homed it, it would always be a little bit different each time... is there any way to linear encode steppers or get really good home switches?

Thanks guys. I have 1 semester left at uni and plan to make videos of all my steps in a clear and easy way to contribute to future people wanting to do the same. I will ask for a bit of help along the way but its all appreciated.

Offline mc

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Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #1 on: July 21, 2016, 06:13:27 AM »
Regarding the Mach 3/4 and CSMIO/KFlop options.

CSMIO will work with Mach 3 or 4. KFlop only has a plugin for Mach 3.

Regarding rigid tapping/indexing, CSMIO you'll need the Threading module, and you're limited by what can be programmed in Mach.
KFlop you can program to do pretty much anything you want it to, provided the hardware will support it. You do need to know some C programming, but there are plenty people to help.

I'd suggest you read the manuals for both, and get an understanding what would be involved to achieve the functionality you'd like.

Offline Hood

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Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #2 on: July 21, 2016, 02:02:11 PM »

I want to run the standard motor at the moment, but have high hopes of rigid tapping and VFD controlled spindle- maybe I should go the whole hog first up?
You can do rigid tapping with a VFD and the CSMIO/IP-A OR ip-s  if you have the Enc module.

1: I am really familiar with Mach 3, but how far along is Mach4 now? With mach 3 I can even do probing and indexing hex stock on a 4th axis, how are the plugins coming along? I would like to use it as its so fast at doing things in comparison but I have so much invested in M3

Gave up on testing Mach4 a long time ago and have not been keeping up with progress so hopefully it should have progressed some. Big issue for me is it will be a big learning curve especially as I struggle with VB and know absolutely nothing about Lua and don't really have the inclination to try and learn as Mach3 more or less does all I need.

2: Buy individual motors/power supplies/ drivers etc or get a kit off ebay/alibaba for about 1000 bucks for 1400oz+ steppers?
Would look at AC servos rather than steppers, they would cost more but the performance difference is night and day.

3:  Controller - I like the idea of CSMIO/KFLOP but never used them, for things like rigid tapping and indexing boring operations would I need this with a servo motor as a spindle and run it as an A axis etc? I have heard you can get servo motors with Step/Dir but how to achieve this will be mind**** without some serious help. -> Lookin at you Hood! I am happy to interpolate the threads with a thread cutter, but the machine is a gear head and I'll convert it to belt drive so I can run 6000rpm. Should I just do that and run with a CNC4PC controller or go the CSMIO

I love the CSMIO, the analogue version being my preferred option, this of course requires your drives to be capable of analogue command but most AC Servo drives are capable of either Step/Dir or +/-10v analogue


4: Ballscrews... 20mm is cheap, 25+ are crazy expensive. 20mm work ok?

Not really sure the size of machine as I have not done a google and the model means nothing to me I am afraid.

5: This is the first time I'll be wiring this up from scratch, and I do have in my mind that I hated the homing and home switches on my last machine always being out. If I turned the machine off, re-homed it, it would always be a little bit different each time... is there any way to linear encode steppers or get really good home switches?
If using servos and the CSMIO IP-S or IP-A then you can do Index homing which means your switches do not have to be deadly accurate as they are just being used for a trigger to tell the controller to seek the Index pulse of the encoder.
You may also be able to do it with steppers and the IP-S if you fit encoders but as said I would look at servos rather than steppers.

Hood
Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #3 on: July 21, 2016, 06:46:05 PM »
Thanks for the reply guys,
the machine is this one http://www.machineryhouse.com.au/M126D - it's a great little mill and pretty rigid, needs a better base though thats the only thing letting it down. I got some 100x100 steel section I'll weld up next week to make a footing for it.
It's a 3 bolt tilt lock which makes tramming interesting but I have a test indicator now.

Anyway, I'm going to read up all on csmio- but I don't really see the large difference between the A and S module. I will get a VFD for the spindle but not sure how to get mach3 to talk to it, I have seen some nice little servo motor packages within budget so there is a good chance I'll go that way. The head is nearly 220 lbs it needs to lift, will 400 watt servo's accomplish that task ok?

There is also the option of flashcut products, but they are belt driven and I don't really trust the backlash on belt drive systems, or is that just me being uneducated?

An auto tool changer would definitely be the prefferred option over rigid tapping, I'm happy to keep a crib and make a draw bar for bt30 pull studs, and at this stage probable just have a flat tool table, but that means indexing the main spindle no doubt. Hood is your ATC on your mill servo driven with indexing? I might have to pick your brain on coding it mach 3.

I looked at 4th axis rotary heads last night, most come with steppers, is it possible to run 3 servo's and stepper motor on 4th? Or would I need to replace the motor? Cheers again all. Project start date is november so I got time to compile a list of gadgets and post them up


Cheers guys, and thanks hood for your input.
« Last Edit: July 21, 2016, 06:56:14 PM by Shamanj »

Offline mc

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Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #4 on: July 21, 2016, 06:55:00 PM »
The difference between the A and S, is A is Analogue +/-10V output, and S is step/dir output. If you're wanting to do rigid tapping, then the spindle will need to be controlled as an axis directly by the controller, not via Mach.

I'd personally look at adding some form of counterbalance to the head, either gas struts or a pneumatic cylinder with pressure regulator.

Nothing wrong with belt drives. A correctly tensioned toothed belt of the correct tooth form will give negligible backlash. If you're using servos, then for optimum performance you're going to have to use a reduction, otherwise you'll not get the best performance from servos.

If you go CSMIO, then the 4th axis needs to be controlled via the same method as the other axis. If you go KFlop with a Kanalog, you can mix and match.
Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #5 on: July 21, 2016, 07:20:13 PM »
Hood whats the advantage of DC or AC servo's - The price is about the same and there are a few nice complete package kits here, I can get 4 for axis and spindle for around 2k up to 1kw. That should be fine for a spindle yeah? I realise I'll have to belt drive the spindle but thats no problem making pulley's on my lathe. You've convinced me to go csmio controller.

Offline Hood

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Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #6 on: July 22, 2016, 05:14:03 PM »
AC servos tend to be smaller for the same power/torque, can get rid of heat easier due to the windings in the body and usually run a much higher rpm.

Regarding the positioning for a toolchange, not sure how it would be done, there is a stop on Index feature in the IP-A and IP-S and on my small lathe it seemed to work well (IP-S) but I think someone had issues with it with the IP-A.
I know CS-Lab did a mill and were indexing the spindle for the tool changer but how they did it I am not sure, it may have been a function of the VFD that they had, best ask them although I think they are on holiday.

Easiest way to see what torque would be reuired for the Z would be to use a torque wrench then get a motor with at least that amount of continuous torque. As mc said, fitting a counterbalance may be a good option, should be relatively easy on that machine.

Hood
Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #7 on: July 23, 2016, 05:08:24 PM »
Gas struts are a common feature in this retrofit and I'll be doing the same.
I'll be doing overkill on the motors currently looking at options over 400watt, I found a nice package of 750 watt motors.
I'm still undecided about the spindle, some good chinese options come up that inlcude a power drawbar and direct drive motor shaft. and I can easily get bt30 pull studs to fit my MT3 taper (atleast I think, I bought one to try it/check it.)

Hood your little mill that has the arm that swings out and indexes, how did you achieve that? I went looking for the video on youtiube and couldn't find it.

I have thought long and hard about what would be right for me in this shop and there is are 3 things.

Good, repeatable accuracy
Loads of power, for good cuts and no missed steps, encoder feedback etc.
Fast (6000rpm) spindle Power drawbar for quick tool changes.

The ATC etc can wait really, and I can interpolate holes or use an idea i had for spindle on time, dwell, and a tapping head. Probably much cheaper and easier then setting up rigid tapping.

Offline Hood

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Re: New maching- Converting HM48 to CNC with mach3 or mach4?
« Reply #8 on: July 23, 2016, 05:27:31 PM »
Only toolchanger on a mill that I have is on the Chiron, Beaver mill just has manual change.
https://www.youtube.com/watch?v=8CHhfy1CanM

Rigid tapping is simple and you only need the Enc module and an encoder on the spindle, so not prohibitively expensive.
Hood