3D Carving Advice - Bit Size

What would you guys recommend as the bit size for a finishing pass on this piece? It’ll be 31x31 inches.

The kicker are these little details in the board itself. I cannot tell if a 1/16" Ballnose at 8% stepover is just too big, or if I’m just being resolution limited by Carveco.

Pre-Machine Simulation:

Post-Machine Simulation

I haven’t run smaller bits than 1/16" before and not sure where to start on deducing size, speed/feed, stepover, etc

For the finest of details you will need to go smaller. I would recommend getting a 1/8shank collet and a small set of ball nose bits for this type of application. If you add vectors to parts of the model you could do portions of it separately with different toolpaths or use a vcarve by only cutting inside the selected vector area that you want to cut.

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I’ll look into investing. My biggest worry is running that small of a bit across the whole relief and having a multi-day cut time.

I’ll spend some time on the Carveco tutorials to see if there’s a way that I could create some vectors over particular areas instead of the whole relief.

Vectric VCarve supports automatic creation of clearing & finish paths using multiple & increasingly smaller bits. Each successive bit carves just the parts that couldn’t be done by the prior bit. You won’t end up doing the whole job in your smallest bit.

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Ah, that’s the solution then. Carveco Maker has a roughing and finishing path built into their relief toolpath, but it still runs the bit across the entire relief instead of only the areas that the bigger bit missed.

If you look at the 3d carving I did in the finished projects the project was a 12x9. I ran 1/4 endmill roughing bit 260ipm in a roughing pass by itself 10min 18sec. Then a 1/8 endmill also roughing pass in separate tool path bit at 145ipm cut time 52min, last was a finishing pass using 1.0mm ball nose 1/8 shank at 60ipm total cut time 2 hr 55 min.
Total cut time for the whole project was only 4 hrs. With the right setup and speeds dialed in you should not run into carves lasting that long even using small bits.
You can mimic the same thing that vcarves rest machining will do and carveco’s model resolution is better than vcarves so it wont get better going there.

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Were you using vectric where you could add a third bit to the same relief calculation?

I would use a 1mm radius 1/4" ball nose bit for fine detail. You can also use a .5mm 1/4" ball nose bit for extremely fine detail. I run mine at fastest spin speed on the Makita. I believe that VCarvePro 11 now has a feature that will allow the finish cut to only carve the places where the roughing pass could not fit for the final detail. Have yet to try this myself. Up until now, I have just used the ball nose bits for the entire carve to save time rather than carving the entire piece twice. At the right speed these bits can take it and produce great results.

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I’ve seen some posts where they use a v-bit rest machining to get into the tight corners of 2d carves.

I would pull out the square you’re concerned about, and just route one in some scrap and see if it’s good enough. That way you can try a few bits/settings and see what works…

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