Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: Mehran_mojaver on July 17, 2021, 04:35:24 AM

Title: Z-axis changing during job & depth is increasing
Post by: Mehran_mojaver on July 17, 2021, 04:35:24 AM
Hello

I have a wood CNC. While I wanna cut a borderline or when I wanna make a 2d model with V-Craving in artcam , the Z axis increasing over time and depth of job is deeper than programmed. For example I set depth on 4mm , in the end depth was increased slowly and reached to 7.734mm.

I don't know where is problem and why it should be work like that. I tried different ways in artcam and changed the model but it's still do wrong job .

Thanks for your guidance 🙏
Title: Re: Z-axis changing during job & depth is increasing
Post by: JG on July 17, 2021, 05:16:33 AM
Is the DRO showing the Z depth increase or is it just the physical depth ?
If he later then the possibility is that the tool is creeping out of the collet - ie. it is 'loose'  -  this will be exacerbated if the cutter is spiral flute 'up-cutting'.
It has happened to me!!

 
Title: Re: Z-axis changing during job & depth is increasing
Post by: Mehran_mojaver on July 17, 2021, 05:52:57 AM
In DRO all things are true , x,y,z coordination are corresponds with real measurements.

Drawing file is correct too , there is no problem in drawing.

But Angels and Depth changing during job, I'll attach the done job picture.
(http://)
Title: Re: Z-axis changing during job & depth is increasing
Post by: Mehran_mojaver on July 17, 2021, 10:37:40 AM
This is my drawing and setting of milling program.
Title: Re: Z-axis changing during job & depth is increasing
Post by: Mehran_mojaver on July 17, 2021, 10:41:22 AM
This is my drawing and setting of milling program.
Title: Re: Z-axis changing during job & depth is increasing
Post by: Mehran_mojaver on July 17, 2021, 01:11:13 PM
Wrong job
Title: Re: Z-axis changing during job & depth is increasing
Post by: JG on July 17, 2021, 01:59:57 PM
It may seem like a silly question but ....   

Is the surface of the work really flat? ie. co-planner with the CNC table.

Do you skim the surface before the V-Craving run?
I don't know the ArtCam program - I'm just applying basic logic.
Title: Re: Z-axis changing during job & depth is increasing
Post by: Graham Waterworth on July 17, 2021, 02:45:32 PM
It looks to be progressing deeper as the job goes so it could be loss of rapid retract steps or is the board lifting toward the middle or as already stated is the bed parallel to the axis rails.

From the start its too deep into the material as per your drawing.

How is the material held down on the table, vacuum table or side clamps.
Title: Re: Z-axis changing during job & depth is increasing
Post by: donramsey on January 11, 2022, 07:53:55 AM
Mine is doing the same thing.  The spoilboard is surfaced, fusion 360 simulation showing constant depth of cut, but machine changes depth (lower) on each pass.  I've installed a different version of Mach3, the z axis is calibrated, and the tool is not slipping.
Title: Re: Z-axis changing during job & depth is increasing
Post by: Graham Waterworth on January 12, 2022, 07:46:27 PM
Mach3 is not at fault its your settings or hardware that is not set correctly.

You need to reduce the maximum speed that the z axis is moving to 25% of what it is now and see if any thing changes.

E.g.

If your velocity is 100 inch then it wants to be set to 25 and do the same for the acceleration.

Title: Re: Z-axis changing during job & depth is increasing
Post by: Ambico87 on January 17, 2022, 08:52:43 PM
Is the cutter pulling out the collet? Easy way to tell is mark a line with a sharpie and see if it moves.