inlay

[germanguitars]

First inlays with this machine since purchasing it a couple weeks ago. No complaints - tight pockets:

[branson]

Dec 14, 2016 15:06:14 GMT -5 germanguitars said:

First inlays with this machine since purchasing it a couple weeks ago. No complaints - tight pockets:

View Attachment

What technique did you use? I've experimented with several different methods and have only had good results with one, but it creates really deep pockets. So if you don't mind me picking your brain, how deep was your female cut vs your male cut and what bit did you use.

[germanguitars]

Using Rhino and RhinoCAM. The Bolivian rosewood oval is 2mm thick. The guitar top is 3mm thick. The mother of pearl is 1.5mm thick. I registered the guitar top along the centerline secured with double stick tape in strategic locations. I cut out the perimeter and the soundhole with an 1/8" 2 flute downspiral. I re-registered the z-axis off the top of the guitar blank and cut the BR oval pocket with the same bit (30 IPM, 100% stepover + corner cleanup pass). The BR oval had been cut with the same bit earlier. Dimensions were exact and too tight to fit. I cut an extra pass profiling the interior and exterior border with the same bit offset as if it were 0.120" to give a 0.005" looser fit. Perfect.
Glued it in place with yellow glue.


The pearl was cut with a 2 flute 0.0325" upspiral (12 IPM @ 21,000) with additional interior feather details added by jeweler's saw and crow's foot. Superglue it down and release it with a heat gun. The pockets for those were cut at 20 IPM @ 18,000, 100% stepover then experiment with the offset until I got from 0.032" to 0.023" - a 0.009" looser fit (assuming that bit deflection is part of the discrepancy). The sharp inside corners are usually the hangup, and I deal with them with a 0.032" wide chisel when possible. Pearl breaks if you force it and spruce likewise dents in like styrofoam around the perimeter ruining the fit. Has to go in clean and easy.
The wooden purfling lines are 2mm deep and 0.040" wide.

[germanguitars]

Dec 14, 2016 23:59:51 GMT -5 branson said:

Dec 14, 2016 15:06:14 GMT -5 germanguitars said:

First inlays with this machine since purchasing it a couple weeks ago. No complaints - tight pockets:

What technique did you use? I've experimented with several different methods and have only had good results with one, but it creates really deep pockets. So if you don't mind me picking your brain, how deep was your female cut vs your male cut and what bit did you use.

Just realized that I didn't actually answer your question about depth - I typically leave just ~0.010" protruding. When I do inlay on ebony I can adjust too-deep pockets by sprinkling ebony dust in the bottom of the hole before inserting the inlay. Lightly tapping on the inlay can send little puffs of ebony dust out along the edges if there are gaps and slowly lowers the pearl into the pocket, which kills two birds with one stone.

[germanguitars]

Success with the 0.023 fret slotting bit. I tested it at a depth of 0.023 up to 30 IPM and settled on 20 IPM. Tight slots and no broken bits. Router runout with the previous machine had made that a struggle.

[waitsmd]

Dec 19, 2016 19:22:34 GMT -5 germanguitars said:

Success with the 0.023 fret slotting bit. I tested it at a depth of 0.023 up to 30 IPM and settled on 20 IPM. Tight slots and no broken bits. Router runout with the previous machine had made that a struggle.

did you get a new axiom machine? i have broken way too many .023 inch bits. run out might be the problem 

[germanguitars]

Oct 2, 2017 10:57:50 GMT -5 waitsmd said:

Dec 19, 2016 19:22:34 GMT -5 germanguitars said:

Success with the 0.023 fret slotting bit. I tested it at a depth of 0.023 up to 30 IPM and settled on 20 IPM. Tight slots and no broken bits. Router runout with the previous machine had made that a struggle.

did you get a new axiom machine? i have broken way too many .023 inch bits. run out might be the problem 

I used a ShopBot for 15 years and had runout issues that caused broken bits at <0.0325". I've only broken bits on the Axiom machine when I push the feed rate a little too high for the material I'm cutting. Cuts are crisp.

[Deleted]

Using those small bits you're getting into micromachining which has different concerns and parameters than standard feed and speed calculators and very low runout is high on the list. You'll want runout to be much less than 0.001" in most cases.