Long time user - rare poster. I’m not having much luck with V bits (engraving bits or the large ones from Inventables). I use PVC trim board from the big home improvement stores for a lot of projects because it machines beautifully with standard end mills. However, with any V bit, I get a terrible surface finish…
Stats of cutting:
DeWalt router speed - 3
Feed rate - 60 ipm
Plunge - 20 ipm
Depth of cut - 0.06" (which is the depth I have the letters set to)
V-bit Flat Area Step Over - 5 percent
I did reduce the step over to 2%, which helped a little, but it’s still ugly. I know I won’t get the same quality as a flat end mill, but is there any tips you have for an inexperienced v-bit user like myself? Any cleanup techniques I should try?
Thanks in advance,
You’ll want to be running the DeWalt on 1
For flat bottoms try using the two stage carving feature. Start with the 1/8" spiral upcut end mill. Then come in with the 60 degree v-bit for the edges. You’ll get a better result.
Here’s a zoomed in rendering of the letter Z. The flat bit does a cleaner job with the bottom and the V bit does a nice job with the edges.
Thanks! I was mostly trying to avoid the 2 stage cutting strategy, but I don’t think I can. I’ll slow the router down for the V bit, and I agree that a flat mill will produce a much better result.
to zachs good points
I second that v-bits are great for profiling and not so good at clear large areas of material especially in pvc foam
for pvc o-flute tools work great and they have special point tools designed for producing a better floor finish on soft plastics
I would suggest onsrud # 63-793
@PhilJohnson suggests v-bit stepover of 1%. Worked for me!