Rhino to cutting

[BrettM]

Question!

Has anybody out there gone from a rhino model -> devloped shapes -> Autocad (2d) and then had the dwg files sent to be plasma cut. If so have you had any problems. I am interested in possible translation problems as well as accuracy of developed shapes. Share your successes as well as failures. I am interested in it all.


Thanks guys

Brett

[duluthboats]

Brett,

I have exported files from Rhino to a CAM program for machining parts + or - .001 no problem with accuracy. The only developed panels I’ve tried were paper, for scale models. That seemed to work fine. One of these days I hope to be cutting full size stuff.

Gary

[BrettM]

Thanks Gary,

This was a bit of a loaded question. I have done cutting/machining drawings for several projects without problems.

This time around is the first I have used rhino to model a complete boat then exported all the frames etc to Acad 2000 from which the shapes are detailed. I am being told by the builder that data which originates from Rhino is causing problems at the cam end. Seems a bit strange to me as I am sending them a dwg file. I believe the problem may be in the translation of the cam program as I can't see any issues at my end.



Brett

Bret,

I have had proplems with the translation from Rhino to Autocad, with sketch lines in Rhino hiding behind surface edges. The cam software may be getting confused because of this. Did you select the entire model and use the edge tools option to check for open edges and bad surfaces, and or deleate any lines that are not surface edges?

[duluthboats]

Two things that cause problems for me when I import files from another systems are. Small unseen segments of a line intersecting the cut path, or small unseen breaks in the cut path. Some CAM programs don’t know how to handle these situations.

Another thing is nurbs surfaces should be changed to a mesh, if you are exporting them. Are the exported files 2D or 3D?

Gary

[BrettM]

Thanks guys,

All of my data is made 2d within rhino (since we are cutting plate) and then selected indiviually before exporting to a dwg file (with the flatten to plane option checked) to ensure that I am only getting the information I need and that it is all 2d.

Once in Autocad I have to add details such as relief holes etc (I am quicker in ACad). I also generally out of habit make sure that the lines are connected as polylines which logically speaking means there are no small gaps in each curve hence solving the gaps issue.

THe objects are then layered into different plate thickness, labelled and finally a titleblock is added to make the file a trackable document before being sent. The builder can then do his stuff(They also have a drawing office for final manipulation)

I still believe that the problem is with the cam software.

Thanks for your input guys.

Brett

[duluthboats]

Brett,

I have done exactly as you described, Rhino 2.0 to AC 2000 to FeatureCam V7 and have had good results. I would have to believe it was on his end.

Gary

Brett, what languages does the cam use ?
HPGL ?
CNC ?
UCode ?
IsoCode ?

what program is it ?
Because they can merge contours, and if that is set to high you loose accuracy. Let them export their workfile to DXf, then you can lay it over your drawing

I had some interesting problems with autocad to Cam.

Your Polylines etc sounds good.

My problem was solved when I made my European Windows was transferred to US. You know the decimal and comma differences.

Cheers Leo V

[BrettM]

Guest,
I have no idea what language, program, or machine was used at the builders end (It is over 2000 km away). Not that any of it means much because I am by no means a cnc expert.

The problem I believe is one that lay with this particular builder. (I also sent the same data to another machine (This time a router) and they cut some samples without problem at a reduced scale.

I can can only believe that the person charged with the program at the builders end sorted out their problems (eventually) because they stopped yelling and the boat became built. Another case of shoot first ask questions later....

Thanks all
Brett

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