I have 3 Tapered Ball Nose bits (TBN) 1/64, 1/32 & 1/16 I’ve read that anything under 10% stepover is good.
Should the stepover be different for each TBN?
What is the benefit of going below 10% if the finish is smooth?
When cutting a 3D profile does it make a difference if you cut it twice? ie 45 then a 90 or 0 and 90? I think the last cut should be with the grain.
I use VCarve Pro, what’s the difference between “Stepover” and “Clearance Pass Stepover”?
I’m no expert but I try to stick around 8%. Anything less takes forever.
Sometimes I will do a second finishing pass at a different angle if the project demands and I can stand the time. Not always though.
Interesting, I don’t recall seeing that “Clearance Pass Stepover” before but I see it now in the settings for a TBN, weirdly not on my other ball nose bits though.
I have it set very high, like 45% but then again, I don’t think its really in play in my carves. I typically have multiple ball nose or TBNs defined in the tool selector for the 3D finish paths.
Thank you for you input.
I use 10% for all my finishing pass settings. Mostly because the math is easier 
I’ve never done two passes since the first one normally gets me the finish I want and I try to go with the grain since it may hide tooling marks better.
I run a 1mm TBN @ 20% stepover. 20% of 1mm is imperceptible, and it still takes a long time. I would reduce the stepover to 8% on a .25 ball mill. This using a raster strategy at 45% angle to a previous roughing pass.
@Jeffish What math are you doing? I figured that by setting a boundary and/or vectors the program did all the math required.
@Pchuk Figuring out what 10% of the endmill size is 
… so I can change the stepover in the tool selection settings window
Ahhh got ya, VCarve lets me set the # or a %. 
CC only lets you enter the stepover. It has a 3D stepover as a % in the tool definition, but it doesn’t use it.
FYI, the math needed is basically…
Re: Two finishing passes:
In my experience, on softer woods, two finishing passes does improve the finish if you leave a small amount for the second pass. I use the ‘Stock to Leave’ setting to leave about 0.10 to 0.25 mm for the actual final pass. The second pass can have an increased RPM and feedrate - I’m moving at 4000mm/min (or more) on the last pass.
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