Roughing and finishing, again

Post Reply
Posts: 57
Joined: Thu Jul 02, 2015 10:40 pm

Roughing and finishing, again

Post by sjj47 » Tue Feb 09, 2016 8:56 pm

I know 3D CAM programs have explicit strategies for roughing and finishing, but right now I'm still struggling with 2D and 2.5D.

Suppose I'm cutting a simple pocket 50mm x 50mm x 5mm deep. I want to do a fast, rough pass with a large bit and a slow, finish path with a smaller bit.

Is there any software out there (free or otherwise) that will set these paths up automatically? Ideally, I'm looking for some CAM program where I can define the pocket, define the bits, and the rough margin. Then the CAM program generates the gcode file (or files) that cuts the rough pass, pauses for a tool change, and then cuts the final pass.

Of course, what I want is that the final pass does not simply repeat the pocket milling operation, and spend most of its time cutting air. I want the final pass to only mill the material left behind by the roughing pass.

I guess I could more or less do this manually, by defining the gcode for the pocket rough cut first, and then defining a finish path with a lower surface starting point (MakerCAM lets us do that). But does anyone know of a CAM program that handles it all?

If not, how do other folks handle the roughing and finishing process?

Shapeoko 3 # 0761 - DW611 - Limit switches - probe
Current tool chains: Inkscape > MakerCAM > UGS | bCNC & F-Engrave > UGS | bCNC

Posts: 1351
Joined: Tue Jan 29, 2013 4:51 pm
Location: Minneapolis, MN

Re: Roughing and finishing, again

Post by twforeman » Tue Feb 09, 2016 9:27 pm

Most CAM programs support this.

CAMBam does it for sure.

You might need to do the roughing pocket, followed by a finish pass at full depth to get the floor and and finish profile to get the walls.
Ender 3 3D Printer
ShapeOko v3 serial #0004 - upgrade thread
All of my ShapeOko related blog posts

Posts: 292
Joined: Mon May 04, 2015 10:46 am

Re: Roughing and finishing, again

Post by xfredericox » Tue Feb 09, 2016 9:28 pm

i think rhinocam has that feature. Rhinocam is not cheap though.

But why the need for a tool change? I'm not an expert but the machine 'should' be precise no matter what. You risk bad alignment in an effort to improve finish quality. Sounds like a contradiction to me.
Visit my blog for updates on my current SO2/lasercutting/... projects.

Posts: 216
Joined: Wed Sep 02, 2015 3:22 pm
Location: Illinois, USA

Re: Roughing and finishing, again

Post by RoguePirin » Tue Feb 09, 2016 9:40 pm

Although not cheap, Vectric's software does this:
  • VCarve Desktop ($349 / £235 / €330)
  • VCarve Pro ($699 / £470 / €660)
  • Aspire ($1,995 /£1,295 / €1,800)
I don't know about their "Cut 2D" line of products.
Shapeoko 3 #677, Nyloc nuts, ¾" HDPE base with t-nuts, Dewalt 611 w/Super PIDv2

Posts: 89
Joined: Tue Sep 10, 2013 3:13 pm
Location: Germany

Re: Roughing and finishing, again

Post by Estlcam » Tue Feb 09, 2016 9:55 pm

Estlcam has this feature for pockets - it is described in the video from 5:06 on:

Estlcam CAM and Arduino UNO CNC controller:

Posts: 101
Joined: Sat Dec 12, 2015 5:57 pm

Re: Roughing and finishing, again

Post by sgth0mas » Wed Feb 10, 2016 3:20 pm

VCarve has a very user friendly way of doing this.

Im sure other cam packages do as well.

Post Reply