I'm doing a run of items using Baltic Birch and the client wants an incised logo which is quite fine - inch high letters with an engraving toolpath and .05 depth, 30 degree v-bit. I've only done this sort of thing in denser materials (aluminum, brass) and am finding the wood is fuzzing a good bit, and given the fineness of the letter, pretty much impossible to clean up by hand, which I'd prefer not to do in any case. Any advice as to how to accomplish this more cleanly would be much appreciated.

In my experience sadly your best option for work like that is to farm it out to a laser shop. A spindle is very difficult even in hard/dense woods (forget about soft woods or ply) to do very fine anything because the tip of the tool is simply rubbing even when you use something like a carbide insert. We have tried fine lettering with single flute insert V bits as well as solid carbide engravers and multi-flute and its nearly impossible to get an acceptable result regularly if at all.

The finer and shallower the lettering gets the more critical material thickness and so on becomes. On top of the rubbing, you start getting into hit and miss situations when you start trying to cut down in the .010" depth range. Then there is the issue of the small elements of the text splintering off and detail being lost which would be an even bigger issue in ply.

So between the setup time, and the failure/reject rate, shipping the parts to a laser shop that drops them on and lasers the part in a minute or two leaving a dead clean end product just makes more sense and the fine detail is beyond compare.

Just my $0.02 based on our experience.

+1 Mark B

All above is correct. However you might try one more time using a mask over the plywood surface when cutting. The mask at least has a chance of keeping the wood fibers stable enough to generate a clean cut.

Oracal is widely available (I get it on Amazon). It is a vinyl sign makers material that can also be used as a mask. In the painted sign making world you would paint the sign surface color, then when dry cover it with Oracal or something similar, then carve through the mask into the sign material. With the mask still in place you paint the carved sections and then remove the mask. Result when done correctly is clean and crisply painted carvings.

BH Davis

Thank you for the responses. I concur that a laser would be the most appropriate tool for the job, and have already tried to steer the customer in that direction.

If you were to running these yourselves, what parameters would you focus on? Very high rpm, slower feed rate, etc.?

BH - Which Oracal product is it that you are using - there seem to be a number of them? Oramask 813, perhaps?

I would be trying various 2 pass methods either a single pass with varying the depth on the final pass or perhaps just running the file a second time like a spring pass to see if it will clean up the fuzz. If the parts are getting a finish you could try first pass, hit them with some finish or a good douse of sanding sealer to try to lock up the fuzz and run the program over or run the last pass.

RPM and feed will be dependent on your tool and burning.

We use oramask 813. Anything is worth a try. Even blue painters tape burnished down with a credit card.

Maybe you talk the person into allowing a little border and you could mask it off and flood the logo area with CA, blast it with some accelerator, and see if it stiffens things up.

I use the Oracal 631. I've tried the Oramask 813 and didn't like it. While made for masking tasks it is a much thinner material than the 631 and I found it lifted off at the edges of letters I'd carved.

The Oracal 631 is a thick vinyl and stays in place due to the stronger adhesive it needs for holding the vinyl lettering to signs, autos etc.

BH Davis

I would prefer to use 60* bit. Mine is a three flute. Try 80 in/min plunge and cut speed. I run at 12k rpm.
You can also try spraying a sealer coat on the ply before cutting. It may reduce the fuzz.
I haven't had any burning while lettering but I dislike Russian birch for its tendency to sliver.

One trick is to use a 2 pass method but coat the letters with some shellac between paths.