VCarving Deeper than the End Mill Cut

[NeathawkSigns]

Hello,
I currently just finished a sign I did in Aspire. It is a simple sign with a persons name on it. 10x23". The toolpath I used was a V-Carve/ Engraving Toolpath. The V Tool I used was a 60 degree .25" with a pass depth of .2. The Flat Area Clearance Tool I used was a .25" End Mill with a pass depth of .2. Both are to cut in .25" inch into my oak board. After finishing the VBit carved about 1/16"-1/8" further into the wood than the End Mill did.

Does anyone know why this happens? Did I do something wrong? I zeroed both bits at the right height too.

Please help! Thanks.

Lindsay

[hh_woodworking]

When you are using the v carve setting the program adjust the depth by the width of the text lines and the tool geometry. V bit would have to go deeper to fill the distance between the lines of the letter. You can check the flat depth box to force a certain depth but you will loose the point at the bottom of the letter.

[zeykr]

I'm assuming you set a flat depth of .25 for your vcarve toolpath.

Some Possibilities:

Did you zero your tools at the same location on the material? And was it an area that was solid to zero the second tool after the first toolpath was cut or could the zzero plate deflect some.

That's a pretty sharp tool, did it poke a hole in the zzero plate? I usually move plate slightly between first and second touch down in zzero routine with sharp bits in case the fast move pokes a hole.

Could a bit have slipped up or down in the collet?

Is the material hold down solid or could it have moved? Sometimes a board can warp away from spoilboard when stresses are released during cut and not using vacuum.

I usually do not do more than one pass with a vbit - I.e you have a vbit cut depth of .2 and cut to .25 deep. I'd probably have either used a bigger vbit or set my flat depth to .2

[NeathawkSigns]

Thanks guys- We suspect the bit moved in the collet when I zeroed it. I found out after talking to Shop Bot that I wasn't putting my collet in to the collet nut and hearing a snap. So we think that was the issue.

A quick remedy for this to save the sign I just re-adjusted my flat tool depth a 1/16th inch deeper and that worked perfect.

Thank you again!!

Lindsay