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zymon
24-08-2018, 01:09 PM
Hi,

I use Zbrush to sculpt my models in the above files to import to CAM software at University.

Zbrush is not a CAD software it uses meshes and I want to use it to carve out artistic organic creations in wood.

Should this be an issue? Because the CNC operator HATES my files and says they are not correct files. I dont need very high engineering tolerances, just beautiful carvings that are the correct size give or take a few mm.

He wont even accept stl. - its only for 3D printng apparently.

Would love some advice and context as to why I am hitting this brick wall and how can I better work with the above files for CNC work.



Regards

johnsattuk
24-08-2018, 05:08 PM
Hi,

He wont even accept stl. - its only for 3D printng apparently.



Well I don't have a printer and regularly use .stl files on my router for wood carvings though only 2.5D.

Eslcam which I use handles stl files and will let you try it if you download it.

John

magicniner
24-08-2018, 05:10 PM
He's right you're presenting him with things which are not CAD/CAM friendly, you should be using STEP and/or IGES if you want cross-platform compatibility.
Use Free Cad to convert your meshes to solids, it's well documented on line how, someone may post a link to instructions.

Fivetide
24-08-2018, 06:09 PM
I used Zbrush in the past and it works fantastic. You need to save as a height map or Alpha. I then used Aspire, which you can create GCODE from Alpha maps in the photo relief tool. Example below. Its really simple.

24711

24712

24713

zymon
25-08-2018, 12:08 PM
He's right you're presenting him with things which are not CAD/CAM friendly, you should be using STEP and/or IGES if you want cross-platform compatibility.
Use Free Cad to convert your meshes to solids, it's well documented on line how, someone may post a link to instructions.

I was under the impression that to convert mesh files like obj. to nurbs files like 3dm. was very difficult and the software that does it is very expensive.

zymon
25-08-2018, 12:17 PM
I was thinking of buying MeshCAM as it states that it will work with lots of Mesh sculpting softwares like Zbrush and MeshCAM told me this:-

"'Most CAM software converts CAD files into the same type of representation as an STL file because the math to calculate a toolpath is much more simple and reliable. As long as the STL is at least as accurate as you need the finished part to be, you're good.''

Ger21
25-08-2018, 06:28 PM
I was under the impression that to convert mesh files like obj. to nurbs files like 3dm. was very difficult and the software that does it is very expensive.

Yes, and there's no need to convert your mesh models.
There are a variety of CAM programs that work fine with mesh models.

zymon
25-08-2018, 11:16 PM
There are a variety of CAM programs that work fine with mesh models.

Assume one is MeshCam. Could you mention a few others as I need to decide which will be best for me.

Cheers

Zymon

Ger21
26-08-2018, 01:45 AM
DeskProto
Cut3D
V-Carve Pro (limited)
Aspire
CamBam

zymon
26-08-2018, 05:01 PM
Thanks for your feedack - Ger21

Deskproto has Student licence with is good.

Found this comparison of the above, which was good for me. https://www.cnczone.com/forums/uncategorised-cam-discussion/165092-cam-mastercam.html


Cheers,

Zymon

Ger21
26-08-2018, 09:34 PM
I've always been a big fan of MeshCAM since the first beta.
However, a few years ago, the developer formed Carbide 3D, and since then, development of MeshCAM has slowed to a crawl.

But it is still being developed. The current version of MeshCAM 7 was released about 4 months ago. But in it's current state, I prefer version 6.

If I ever get a machine running with a rotary axis, I'll probably invest in a copy of DeskProto.

zymon
26-08-2018, 10:20 PM
If I ever get a machine running with a rotary axis, I'll probably invest in a copy of DeskProto.

Is Deskproto mainly for rotary axis. I am only using a flat bed CNC.

Simon

Ger21
26-08-2018, 10:32 PM
No, but it has a lot more rotary axis features than anything else.

Neale
27-08-2018, 08:25 AM
I'm not quite sure if you want to convert your STL files to a 3D CAD format, so that your machine operator can then run it through his favourite CAM package, or whether you want to do the CAM yourself. I have used Fusion 360 to do the latter (and it's free if you are a student). Converting to a standard 3D file format is always going to be a little more difficult as it's not really a logical thing to do in most cases as straight to CAM/gcode makes more sense - but you need to know machine parameters like cutting speeds, cutter sizes, etc, to do it properly.

zymon
03-09-2018, 12:32 AM
How would MesCAM/Deskproto compare with BobCAD? Especially the new version.

I had a look at the previous version of BobCAD and found it looked rather complicated. Can it do more than the other 2?

Zymon

Ger21
03-09-2018, 02:54 AM
Run away from BobCAD as fast as you can, and don't look back.