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Cutting out letters help

I’m new to xcarve, have only had it about a month. It’s definitely been a a steep learning curve, but slowly figuring it out by trial and error.

I’ve been cutting out letters and other designs but the biggest problem I’m having is that there’s always a lot of splintering of the wood and requires a lot of sanding. Even after a lot of sanding and use of the dremel they’re still not as smooth looking as I’d like.

I’ve tried Baltic birch plywood, both 1/8 and 1/4 inch depths. I’ve tried several bits, the 1/16 and 1/32 fish tail spiral downcut. As well as the 1/8 Compression.

Any tips or tricks? Or is this just the reality of a cnc? Thanks!

I used these on 1/2" plywood yesterday from Home Depot and they cut remarkably clean, very little sanding. I also use the inventables two flute straight bit for 99% of what I cut out

You might look at downcut bits or compression bits.

A typical bit has a spiral that lifts material up and out of the workpiece. When it does that, it often produces splintering on the top of the workpiece.

A downcut bit is spiraled the other way and drives material downward. This is not as efficient at clearing the cut path, but chips typically exit out behind the bit. This also minimizes the splintering at the top of the workpiece.

Compression bits are spiraled both ways. They are upcut from the tip to the middle and downcut from the middle to the collet. If you are using a compression bit and cutting through in one pass, the bottom of the workpiece is being pulled up while the top is being pushed down. This makes for very clean cutting.

There are a number of YouTube videos about the bit types.

Other than what I mentioned above, you can also try placing your good plywood between an upper and lower sacrificial plywood. This usually does a good job keeping things clean.

If your material is reasonably thin, you can also try some straight flute cutters. These don’t tear as much as the spiral cutters.

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