Pocket cut not leaving 1/4 inch even border

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pipp
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Joined: Sun Apr 21, 2019 4:50 pm
Model of CNC Machine: Piranha FX

Pocket cut not leaving 1/4 inch even border

Post by pipp »

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Hello. 1st I created a pocket cut on a 6" w X 3.5" h board. See pic. I had set my zero at the bottom left corner of the material. The cut should have left a 1/4" border around, as the box I created in my drawing was sized 5.5" wide X 3" height, and centered to the material. As you can see in the picture, (pic 1) the amount of material left around the border is uneven on all sides. Thinking I was off in where I had me zero,I created another cut, making my zero at the center of the material-see pic 2. This time my material was 5"wide X 3.5 Height, and the box was sized at 4.5" wide X 3" Height. I set my zero in center of material and ran the cut. Again the border is uneven. Any suggestions on what I am doing wrong?

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mtylerfl
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Re: Pocket cut not leaving 1/4 inch even border

Post by mtylerfl »

It appears to me that you are not able to reliably position your material accurately enough by whatever method you are using.

There are ways to do that, but if you want to “keep life simple” perhaps just use a larger material blank, cut the pocket/letter area, then run a Profile cutout around the perimeter (spaced/offset as desired). This will assure an even border all around your pocketed area.

Others may chime in with “less simple” but bonafide techniques for accurate positioning as an alternative to using a larger material blank, as described. If you are making a jillion of these plaques, all precut to the same size, then alternate methods will make more sense.
Last edited by mtylerfl on Sat May 04, 2019 11:25 pm, edited 1 time in total.
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gkas
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Re: Pocket cut not leaving 1/4 inch even border

Post by gkas »

It looks like the board is mounted off axis. To test, mount another board you know has a 90. Zero your XY axis on the bottom left. Zero the Z slightly above the board. When you move your bit, it should follow the edges of your board. If not, your method of alignment is off.

pipp
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Joined: Sun Apr 21, 2019 4:50 pm
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Re: Pocket cut not leaving 1/4 inch even border

Post by pipp »

Hello and thank you. I don't know what I was thinking. The answer to my problem should have been obvious. Thank you both for pointing it out to me and responding. :D

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