Cutting a 3d part

[wwwmthboardscom]

Hello Im using turbocrap to draw an arc then cut it into wood.
Its 66 inches long. When I get that big of an arc in turbocad, it show the arc as strait lines like a hexigon, and it cuts that way too?
I have done this with autocad inventor and it cuts a perfect arc with no strait lines. Why cant turbocrap do this?
I save as an stl file then load it into free mill, then mach3

[moldcore]

I don’t have either program but my guess it would have something to do with either the cutting tolerance setting in the CAM program or the precision tolerance of the stl file in the CAD program. STL files suck for machining but if that is what you have to deal with then crank down the tolerance as much as possible. All those facets need to be as small as you can get away with or recreate the arc in the CAM program.

[mcphill]

Yup, I bet the resolution in the STL file is what is getting you. You will be much better off with a different file type, or greatly increasing the resolution of the STL approximation.

[BurrMan]

STL is a polygonal format which means NO ARCS.. Only staight lines.. Freemill supports the 3dm format which is a NURBS format, which means true mathematical arcs.

I think TurboCad can create BOTH polygonal AND NURBS entities.. Be sure you are creating NURBS and export with that format as well.

[LeeWay]

There is also a setting or two that can be set in Turbocad. I don't know what version you have though. Go to Options and then toward the bottom of the drop down will be ACIS. I don't think you have it in designer versions.
There you can set it to quality mode and uncheck degenerative faceting. This will help.
Click on 3D properties and you should be able to increase the number of facets, thereby decreasing the rough edges. The higher you set it, the more ram it will use.

[wwwmthboardscom]

I have saved what I need cut in all files but stl is the only one that will open in free mill, the 3dm is not an option in turbocad. I was able to get the resolution one up which helped but still strait lines. Also I dont see an option for acis in the Mac turbo cad. This is a 1000 dollar program some how Im sure there is a way just cant find it.
I guess I will load up autocad inventor with my mac which will take all day.
I stoped using autocad inventor because the export dxf files for 2d cuts never worked.. Ahhhhhh Wish I could afford solid works!

[LeeWay]

What version of TC is it?

[wwwmthboardscom]

its TurboCAD Mac PRO v5 its just the trial but it full functioning trial for 30 days.

[LeeWay]

Don't know anything about the Mac version.
Here is a link to the TC forum that has helped me in the past.

TurboCAD Forums - Index

They have a section on the Mac versions.
You are correct. It should be fully functional.


Sorry. This link is the Mac forum.
http://tcmacforum.imsisupport.com/