Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: radrawing on April 12, 2007, 02:48:21 AM

Title: Missing steps
Post by: radrawing on April 12, 2007, 02:48:21 AM
Hi All
I thought I had done it but I didn’t. I have been messing and building my router now for about a year. I have now got to the stage were I can cut something. My setup was.

Hobby cnc board
140oz steppers 8 wire
X 20dia screw
Y 20dia screw
Z16dia screw all stainless steel.

computer was
500Mz process
256ram
and nVidia 64meg card
with win 2000

I have cut out shapes to see it working. It goes very good and is a good feeling.
Last week I downloaded Vcarve demo and put in the Bulls head sign test file.
I was amazed what this was doing. Then after 5-10 minutes I heard the motors stall and the DRO kept going then the motors started and cut well off line. So I looked through the forum to pick up some tips. I thought, computer. So yesterday I bought some bits and built a new one just for my machine.

Processor 3.3Gz
Ram 512MB
64MB nVidia card on board
win 2000

Last night set it all up and it was so quick loading and changing screens. But guess what, it done it again. Same code different position.

Roger
Title: Re: Missing steps
Post by: Hood on April 12, 2007, 02:59:02 AM
Slow the Vel and accel down a bit on your motors and try again, also look to see if you have enhanced pulseing enabled (General config page)
Hood
Title: Re: Missing steps
Post by: radrawing on April 12, 2007, 03:07:33 AM
Hi Hood

I have slowed down the Vel andAcc two thirds and done another cut. The same happened. Enhanced pulsing? Should this be checked or unchecked? Ill have a look tonight.

Regards
Roger
Title: Re: Missing steps
Post by: Hood on April 12, 2007, 03:09:51 AM
I think the the word  on the enhanced pulseing is it usually makes big improvements  when enabled and only very rarely can it cause any probs.
Hood
Title: Re: Missing steps
Post by: Brian Barker on April 12, 2007, 11:31:05 AM
Roger,
please try Sherline mode... It may help..
Title: Re: Missing steps
Post by: zoltan on April 12, 2007, 01:16:53 PM
Hi,

I still have same problem. Initially, I found out that only for files bigger than 500K, but with version 61, the size does not matter. The machine is missing steps randomly, no reason/clue why. It just skips steps. I have run the driver test (I have found out on ver 61) and everything seems OK. I reinstalled an older version, before ver 49 when I had first time this herratic behaviour of losing steps and no missing steps.

Zoltan
Title: Re: Missing steps
Post by: zoltan on April 12, 2007, 01:18:16 PM
I did not try yet ver 62.

Zoltan
Title: Re: Missing steps
Post by: Brian Barker on April 12, 2007, 01:34:05 PM
Do you have backlash on?
Title: Re: Missing steps
Post by: radrawing on April 12, 2007, 02:24:23 PM
Hi all

Un-checked the enhanced pulsing Hood and every thing stop all together so checked it back in and restarted.

I don’t know if the back lash is on I have never been there If its off at default then I would say its off. Its never been touched.
I will try Sherline mode tomorrow. It’s late and I have locked up.

Something to add my motor stall at 1500mm per min. It runs nice at 1000 but I have set them to 500.

Roger
Title: Re: Missing steps
Post by: radrawing on April 13, 2007, 03:07:42 PM
Brian

Changed to Sherline mode and run the same code. OK. Cut first time and no problems. Nice. ;D

Now then. One more thing.
My Y axis motor sounds like its tight. ??? When I turn the power of I can turn the shaft with my fingers. Vcarve has a door panel. I thought I would try this next. Run the code and got halfway up the door on a straight run then my Y axis stalled. >:( Now I’m thinking that there could be something wrong with the motor also. All though the first cut of the bulls head was OK but then I did change to Sherline mode. Tomorrow I will swap over my X Y motors to see if it still dose it.

Thanks Brian

Roger
Title: Re: Missing steps
Post by: Brian Barker on April 14, 2007, 09:31:53 PM
What did you find by swapping your motors? It sounds to me like a hardware problem :( They are VERY hard to find at times!
Best of luck and we are here to help.
Brian