Lightwave 3d and cnc machining

[breakstuff]

Hi, i new to all this and I have been doing lots of reading but it is tough to find info for the hobbiest on CNC.

I pretty much set on getting a maxnc 15cl from a guy who sells them frequently on ebay.

my problem is the design aspect. I use lightwave 3d. It is very easy to use and accurate. The problem is it has a hard time exporting it's accuracy to a machine capable format.

Has anyone got experience useing lightwave so that the structure of the models is not misinterperated on export?

I made some sweet models and sent them to a machine shop to make my parts for me and they ended up redoing everything because the converter software looked at most of the polygons as hollow objects instead of solids.

thanks in advance

[HuFlungDung]

Hi Breakstuff,

You sure have a funny nick

Anyways, what kind of file format does lightwave export to? Not only its native format, but see if it can export to igs or iges or step file types, whatever. You could download the demo of Onecnc Mill professional at www.onecnc.com and see if you could successfully import one of your files. The demo will render it for you too, so you can see what it looks like.

[Larry Callahan]

I know this is an old thread but I now have the same problem. Has anyone solved this?

[yohudi]

Originally Posted by Larry Callahan I know this is an old thread but I now have the same problem. Has anyone solved this?

Hi there, I'm not a big user of lightwave.. but I have used it as part of my work in the past.. I used the .3DS export functions in LW to transfer models into 3D studio. I always had a problem with holes in meshes.. but was pretty much always able to "cure" the problem by appling a 2-sided material to the model. This demonstrates that the hole is just a flipped face.. i.e. the face is there but it's "face normal" is pointing the wrong way.

sounds like the "hollow objects" prob mentioned is related to face normals being flipped or inverted.. so the gcoding app thinks theres a hole where there should be a face.. if it is then you might be able to gcode this kind of model with some software that doesn't concern itself with which way the object faces are pointing..

I did some face normal testing with cut3D to see if it could invert a model and cut a mould.. happy to say that it was a successful test.. I made a dome and turned it inside out.. to make a bowl ...there was no base on the dome. In 3D terms this could/should have made the inside of the model invisible to the coding.. as ALL the faces were pointing the wrong way... Cut3D coded it with no difference to one where I'd flipped the face normals to account for turning the model inside out....

might be worth trying export of the model from LW to 3DS format and fire the cut3D free trial software at it.. I think there's a GOOD chance that it might ignore the flipped normals .

BTW I have no affiliation to vectric I just use their software myself... it's pretty useful for coding the more freeform 3D stuff.

hope this helps you out.. and would be interested to know if it worked...

[ger21]

I use a Lightwave .stl plugin from here. It's actually an L Script.

http://www.chromecow.com/downloads/lscript/

The .stl's load into MeshCAM just fine.

[yohudi]

Originally Posted by ger21 I use a Lightwave .stl plugin from here. It's actually an L Script. http://www.chromecow.com/downloads/lscript/ The .stl's load into MeshCAM just fine.

A better solution by far by the sound of it...