3D contour surface finish

[macklebee (Michael)]

Trying my first attempt at 3D contours using estlcam’s rough and finishing gcode outputs, and I am curious on what type of surface finish I should reasonably expect. Is this a function of quality of the wood (test piece was just done on scrap 2x4), the size of the bit, the stepover, the spindle speed, the feedrate, etc? Just trying to figure out what parameters I should try tweaking to get better end results.
Here is pic during the finishing run with a 1/8" ball mill:

and the end result:

Appreciate any feedback.

PS. Anyone familiar with Estlcam? if I export the roughing and finishing in one *.nc file, will the shapeoko stop for a tool change? Using Estlcam because I have never had any luck figuring out fusion 360.

[neilferreri (Neil Ferreri Ω)]

The scalloping can be minimized by using a smaller stepover. Do you know what your stepover setting was?

[macklebee (Michael)]

15% in estlcam’s settings. Thanks - I will try lowering that and see what the affects are.

[WillAdams (William Adams (Carbide 3D))]

Note that stepover is kind of odd — you actually want to increase stepover %, and have a smaller area which doesn’t overlap — see the image at:

https://wiki.shapeoko.com/index.php/Endmills#Stepover

[macklebee (Michael)]

yep, I was confused by that in estlcam as it is opposite from shapeoko’s description of stepover.

estlcam defines their use of the stepover value as:

• out of curiosity - Does Carbide Create have any future plans to implement importing 3d models to create 3d toolpaths?

[WillAdams (William Adams (Carbide 3D))]

I don’t think Carbide Create will accept 3D files — that would compete with MeshCAM — but you’d have to check w/ @robgrz or @edwardrford or @Jorge

[Vince.Fab (Chippy McChipload)]

Here’s a ball nose surface quality calculator if you want to get techy with it

http://www.iscar.com/ita/Calculators.aspx?units=M#

[macklebee (Michael)]

yep - changing the stepover was a big help… thanks for the suggestion.