I have a file I have cut roughly 100 times perfectly. The other day I set the machine up for a nearly 20 hour cut in Damascus. Once finished, I changed the machine setup back to continue running my small production file.
Any interior through hole or pocket hole cut is coming out 0.52mm over size, and the final piece X Y cutout is coming in 0.52 UNDERsize.
NO, I did not specify the incorrect tool. That never happens, right?
Any ideas?
And yes, the machine will do Damascus, very slowly.
Is this a brand new endmill? If so, what’s the tolerance on them? Did you cut a slot to measure this particular endmill’s runout? Looks to me as if the endmill either wasn’t properly seated, or was suffering from extreme flex curing the cut (bad endmill?)
Could the blank be out of spec.? (Too hard?)
Very nice piece! (reminds me of the Atwood Snakebite I never managed to find to buy).
I should specify, I am cutting wood. I have done this cut over 100 times successfully, with this exact endmill. This was not the endmill used to cut the Damascus.
It is a .06325" endmill and it measures .061.
what were your machine setup changes?
What size slot does the endmill cut in this sort of wood?
Have you cut a circle-diamond-square in this wood to calibrate for runout in this material using this endmill?
I have not. Should I? I have produced several pieces with this exact wood blank, and this exact endmill. Problem did not occur until changing the setup back to this work, from the Damascus job.
Have you cut the Damascus file previously?
Hopefully @ApolloCrowe or someone else w/ more experience w/ a Nomad can address this.
William
No was the first time cutting the Damascus. I am held up at this point with the machine doing this. I need to continue producing my other file, and dimensions are critical. I am at a loss, this is strange. Could working the machine so hard cutting Damascus have caused an issue?
Waiting on response from Apollo. In the mean time I am dead in the water.
Does Nomad have a calibration for belt stretch?
Do I need to reset my controller settings?
Really at a loss, and I am losing time and materials.
Only the initial Nomads had belts (and they came pre-calibrated, though I suppose the belts could lose tension / need to be replaced with usage). If you have the more recent Pro version, then it uses leadscrews.
Hopefully Apollo can chime in presently — I don’t have a Nomad, so can’t help much beyond theory.
I’d cut that slot and measure it. It sounds like you’ve got some increased run out from somewhere.
I manually cut a 1mm DOC slot in a piece of pine by jogging the machine, spindle on. My measurements show a reading of 0.1235" to 0.1250", using a 0.125" cutter.
@rayjneal
Send some pictures to support so we can help figure this out. You have mentioned a .02" discrepancy and you also mentioned a .063" cutter making a .061" cut.
Let’s see if that information can lead us to a solution.
@ApolloCrowe
I have a .063" cutter that mic’d at .0615".
I have a .125" cutter, mic’d at .125", that makes a cut width of .125".
On blind holes, and through holes, the final dimension measures .35mm under size, and the final part dimension height (have not measured width) on average is .35mm OVER size.
Not sure what pictures you guys would need. I am trying to give all pertinent information.
I will need to take a closer look but it appears their may be noticeable spindle runout upon startup. It seems to have a slight wobble. Endmill protrudes .7" from the collet end. I have removed nut and collect from spindle and cleaned debris, as well as brushed any possible debris from the taper.
I have reseated the collet to the nut, hearing the audible click. It does appear to fall out of place unless very delicately handled while installing on the spindle. Could collet and nut be worn?
Upon closer inspection the collet nut appears worn/elongated on the seat. @ApolloCrowe @robgrz someone please verify.
It would seem that runout/wobble would have an opposite affect. IE holes oversize, final part dimension undersized, not the opposite as I am experiencing.
