Cutting Depth

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David Corrigan
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Cutting Depth

Post by David Corrigan »

I am cutting out some 1/8 inch hardboard and having a slight problem. I am Z zeroing to my spoiler board and setting my cut depth to .14 inches but it still won't cut through the material completely. My material thickness is set to .125 inches. Can anyone explain why I am not cutting through to the spoiler board?

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Mark's Wood Chips
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Re: Cutting Depth

Post by Mark's Wood Chips »

Are you certain that the hardboard is 0.125"? Measure it with a caliper if you have one as a reality check. Another possibility is that the cutter is loose and pushing into the collet.

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David Corrigan
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Re: Cutting Depth

Post by David Corrigan »

I measured the material thickness with a caliper and it measures .122 inches. However, I thought that if you Z-zero to the spoiler board you should at least be cutting to the bottom surface of the material regardless of what the tolerance is on the material thickness. Am I thinking this wrong? I also tightened the bit into the collet to prevent any slippage.

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Re: Cutting Depth

Post by IslaWW »

After you zeroed the Z to the spoilboard, have you moved the z back down to verify it was actually zeroed there? Use command "MZ,0" from the keyboard
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David Corrigan
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Re: Cutting Depth

Post by David Corrigan »

Good idea! After moving the machine back down to verify, I used some feeler gauges and measured .03 inches between the bit and the spoiler board. So what is this telling me? Do I have a problem with the machine?

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Re: Cutting Depth

Post by martin54 »

That's actually quite a bit which would explain why you aren't cutting through the material, is this the first time you have experienced this sort of problem?
I would repeat the z axis movement & then zeroing it half a dozen times to see if the error is consistent at 0.03" or if it changes. When you used the keyboard command to zero the axis was it at the same spot that you set the zero initially ? If your spoilboard isn't completely flat then that could give you a difference in readings if you don't use the same spot.
Have you checked the z axis for backlash ? If you have that sort of movement then you should be able to feel that quite easily :lol: :lol:

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Re: Cutting Depth

Post by mtylerfl »

David Corrigan wrote:Good idea! After moving the machine back down to verify, I used some feeler gauges and measured .03 inches between the bit and the spoiler board. So what is this telling me? Do I have a problem with the machine?
Another thought...

Are you using a Z-Zero Plate? Perhaps your machine control software settings are not taking into account the thickness of the Z-Zero Plate by the correct amount (i.e., the settings are off by 0.03" and need to be changed in your control software to match your particular plate thickness).

(BTW, it's spoilboard, not spoiler board.)
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David Corrigan
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Re: Cutting Depth

Post by David Corrigan »

I think I found the problem. It appears that because I had the bit too far up in the collet, the collet was bottoming out on the surface of my material. I pulled the bit farther out of the collet and ran the tool path again with success. Problem solved and another lesson learned.

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Re: Cutting Depth

Post by mtylerfl »

David Corrigan wrote:I think I found the problem. It appears that because I had the bit too far up in the collet, the collet was bottoming out on the surface of my material. I pulled the bit farther out of the collet and ran the tool path again with success. Problem solved and another lesson learned.
Well, glad it was a simple fix anyway! :D
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