Messages

91

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 07:47:24 AM »

Yeah, thanks for the offer.

Been looking at drives, I know these are cheap for a reason but surely they should work?

I still don't know if the signal quality is an issue.

It runs fine open-loop so its definitely encoder related.

I have no other drives to try out, if i was to buy another i would have to be 100% certain it would work first and it would need to be affordable i.e. probably 2nd hand.

I know this issue popped up on my first build, checked the thread but cant find it, i think it was when bench testing a drive and CSMIO - it would fault out but back then i put it down to lack of set up etc, since fitting on machine, none of the drives have ever reached full speed so the problem never returned.

Doesn't help but i'm sure it happened.

92

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 06:57:42 AM »

Its not the motor/encoder/spindle bearings

I swapped the motor for my X axis one and got same fault, the X Y Z motors never ever reach full speed so never see the issue.

Its not the spindle bearings/heat causing as it faults with belt removed.

93

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 05:01:08 AM »

When you go to Plugin Control button and then choose the CSMIO do you see any red numbers for the Internal position counters. A friend did on one axis on his lathe, can't remember exactly what the cause was but I seem to recall it was bad encoder signals and the CSMIO was picking it up and showing the values in red which indicated errors.

Yes, always have done, sometimes get the "check encoder connections" warning at start up too.

It seems connected to the fact that my controller is powered up before the drives are - nothing i can do about that as the drives only have the one power option, not split power & control supplies.

The spindle encoder does not show up in that window though.

94

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 04:58:48 AM »

Hmm, whats bothering me is the fact that merely connecting open cable caused the degraded signal - you can pull the connection from the controller and probe the open wire and the result is the same yet the drive seems to be sending good waveforms out form its connector.

I just really don't know if this a false lead or not yet but i don't like it simply because its there.

95

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 04:27:07 AM »

Right, before i go any further, i did some poking with the 'scope, my problem is i don't know if what i am seeing is an issue or not so thought it best to get this on the table first off.

four pics attached, 3 taken at the controller end of the cable, 100rpm, 1500rpm and 2800rpm

one pic taken at the drive with cable removed and the spindle just flicked by hand.

So, my questions:-

Do these show a problem?

Why is there so much 'crap' in the signal at the controller end of the cable when i am using proper encoder cable with the pairs twisted and used for each channel as required?

This interference appears at all encoder connections on the controller, I can't easily get data though as i'm on my own and holding the probes plus jogging etc is a bit dangerous.

Its not a ground loop as disconnecting the cable screen made no difference at all to the signal.

If its normal, i'll carry on with motor swapping etc but don't want to start pulling it apart for no reason

96

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 03:00:43 AM »

Ok, thanks.

I'm going to throw the 'scope on it again and watch what happens as speed increases.

Then I'll try swapping some motors.

I'm reading back through my massive build thread because this sounds very familiar from when i was first tuning my axis drives....

97

General Mach Discussion / Re: Mill or Turn?

« on: May 26, 2019, 02:47:55 AM »

Ok, thanks Hood, thats the ENC module, i guess you have the same in the spindle drive encoder setup too?

I'm not hooked up to the ENC module yet, just the controller.

98

General Mach Discussion / Re: Mill or Turn?

« on: May 25, 2019, 04:44:43 PM »

They get warm, i'm paranoid about things that run warm

At the end of four runs of 4 minutes each, they were fairly hot but ok to hold by hand so i guess below 40c ?

I can easily flip the belt off and do air-cuts to prove it out.

A friend has just suggested it sounds like the controller (CSLabs) is having trouble counting pulses at full speed.

The other axes have the same drives/motors BUT one big difference is that they never run flat out because i have the mill tuned pretty low as far as rapids go, maybe only running 2000rpm max on X & Y drives.

I can pull the belt off the knee axis and connect that to this drive - see if it faults out, that will prove its the motor or not, if it still faults it points towards the CSLABS box i think ??

99

General Mach Discussion / Re: Mill or Turn?

« on: May 25, 2019, 09:14:43 AM »

Ok thanks Hood.

No idea what to do here really, i should just have bought a small CNC lathe i think, this add-on is killing me.

Today i replaced the cable that joins the drive to the controller, used proper twisted-pair servo cable (damn expensive) thinking it might be interference but no change at all.

I tried it at 2980rpm and it ran ok manually, i edited my code so the max CSS limit was 2980rpm and it passed three dry-cuts perfectly.

Feeling optimistic i put tool to metal and it actually made a part, tweak the tool offset to get size on, made another - OK.

Another tweak because i went the wrong way  and it made another part OK.

Run another and I get the ePid fault, it wasn't even running at max rpm i think, that is the point where i gave up and turned it all off, another 6 hours of messing and no result.

The parts are in the picture, apart from issues with stringy swarf, it worked really well which makes it even more annoying.

I was going to pull a drive from another axis but i have to pull the cabinet apart for that and i can't risk upsetting the main mill setup as i use it a lot.

At present it's half an inch or maybe 12mm away from the dustbin 

100

General Mach Discussion / Re: Mill or Turn?

« on: May 25, 2019, 07:05:43 AM »

But any ideas why my spindle faults above 2985 rpm?