Messages

251

General Mach Discussion / Re: Stop CV issues...

« on: September 13, 2015, 01:51:32 PM »

Terry

Generally I agree with everything you've said.

However - look at WHERE the gouging is happening on the picture. That should have NOTHING to do with slowdown because at that point there shouldn't BE any slowdown.

Of course there obviously IS, which is why I've suggested what I have.

252

General Mach Discussion / Re: Stop CV issues...

« on: September 13, 2015, 11:11:30 AM »

No that's perfectly fine.

Sorry Dave - it's actually N0370 etc. and it's not quite what I thought now I've looked closer.

However, I'm guessing it (and possibly some others) are still the cause of your ills. The thing is your toolpath has loads of REALLY short lines joining your "intended" lines to arcs. The one on line 370 is 0.07mm long (where I think ONE of your "blips" is). I'm thinking this is what's tripping up CV with angles >.

NOW - it shouldn't - but I seem to recall REALLY short lines having bad effects sometimes in CV so I'd get rid of them and see what happens.

What CAD/CAM do you use?

Are the 2 "blips" in your photo the only two?

253

General Mach Discussion / Re: Stop CV issues...

« on: September 13, 2015, 09:48:06 AM »

take a look at line N0360 and N0490 and tell me what you see.

254

General Mach Discussion / Re: Stop CV issues...

« on: September 13, 2015, 08:39:11 AM »

but here should NEVER be a "blip" with CV - anywhere - period. If there is then CV would be pointless - and it isn't.

maybe time to post some code and a description that demonstrates your problem(s).

255

General Mach Discussion / Re: Stop CV issues...

« on: September 13, 2015, 07:04:54 AM »

I think the main crux of my question was is there way to stop the jerks when transitioning from a straight to an arc when using stop-cv???

The problem here is that if you have a line tangentially joining an arc then it is essentially pointless using stop-cv on angles > because there IS NO angle.

The fact you've asked the question would suggest that you do indeed see a difference. That is baffling because it makes no sense.

256

General Mach Discussion / Re: Stop CV issues...

« on: September 13, 2015, 06:21:17 AM »

Bit confused here Dave. TP asked if you were talking about (corner) rounding and you said yes but then described the problem as top edge bevelling. Which is it you're concerned about?

257

General Mach Discussion / Re: Slave axis not slaving when running g-code.

« on: September 11, 2015, 01:05:31 PM »

sounds like you're using the same pin for the A axis step and the spindle relay.

258

General Mach Discussion / Re: Odd setup issue, new machine...

« on: September 11, 2015, 10:22:28 AM »

If you really want to get to the bottom of it I'd scope it all but that's just me. I personally would want rid of the opto chain though. Anyway - have fun.

259

General Mach Discussion / Re: Odd setup issue, new machine...

« on: September 11, 2015, 09:09:59 AM »

It does seem to have fixed the issue though which is the important part.

True, but then so did your original scheme apparently.

However, upon changing the step active low settings for Y&A seems to fix the issue.

But, I cannot see why these two axes need opposite step signal levels???

Any ideas here?

I've simply tried to answer the WHY bit.

260

General Mach Discussion / Re: Odd setup issue, new machine...

« on: September 11, 2015, 07:53:57 AM »

Just noticed that on MYCNCUK you stated that all was well with a different BOB. I think there's your answer. It sounds as though your current BOB (not the the drive) is the thing that needs the longer pulse width. This usually down to a BOB that uses optos that aren't as fast as they could/should be.

It also raises the issue of driving optos (in the drive) with optos (in the BOB). Not generally a good idea.