V-Inlay Method - Question

[mfirlott]

I am testing my skill set out with the Jank method of doing v-inlays...again. Method works out great but I'm having an issue with the finished product. Seems to always be the same fail

Question...what do others do to prevent breaking off small or skinny pieces of the male inlay?

This time...I was cutting a flower as another test subject and the narrow parts of several petals broke off as did most of the stem when I was cutting out the male inlay. I thought maybe the grain direction was partially at fault but if I rotate the piece, I'm sure that just a different part will break off.

My settings are:
Walnut for the female pocket and maple for the male inlay. Both very solid hardwoods.
Male Inlay:
• Start Depth = 0.18”
• Flat Depth = 0.10”
Female Pocket:
• Start Depth = 0”
• Flat Depth = 0.2”
Using a 1/4" 30 degree V-Groove bit at 18,000rpm.

Any suggestions to prevent breakage of small parts?

Thanks for any suggestions.

[FixitMike]

Try running two male cuts, the first with a start depth of .15". Also, the tool feed rate may be too high. Another help may be to use a V bit with a larger cutting angle.

[randyr]

I do a lot of inlay work. Walnut to me is fairly open grain and sometimes I have problems with chipping on fine detail as well. When using it, I try to use it for the inlay material so that If there is a problem, it can be patched with a glue/dust mix. It’s harder to make an unnoticed patch when maple is the inlay, but hard maple generally works well for either the base or inlay. Rarely do I have chip out with it....just walnut.

But for doing highly detailed inlays, I really prefer more dense woods..Blackwood and boxwood go really well together. Bloodwood, Purple Heart and bubinga also work well.

Also...I pretty much always run the toolpaths twice....just seem to get a cleaner surface. Run once...clear out the chips, then run again. But mine are mostly small...so it doesn’t take much extra time.

Randy

[mfirlott]

Thanks Randy and FixItMike...I'll try both ideas.

I did a simulation with a wider bit and the base of the male inlay does appear to be much wider/larger. Maybe 30 degrees makes the little pieces too narrow and easy to snap off and disappear into the vacuum.

I'll also try two cuts on the male to reduce the pressure on the wood to see if that helps .

Thanks guys!

[mfirlott]

FIXED.

So I did ALL 3 changes and that seems to have done it. No small broken pieces.

1) More careful with grain orientation.
2) Less steep bit. Used 60 degree instead of 30 degree. Small/thin pieces were not as narrow for the male glue in parts.
3) Did the male v-inlay in 2 steps so was a lot less aggressive in the cutting.

Thanks all...will add these bits of wisdom to my Aspire Notes file .