Need help making 3d mold

[DW1]

Hi everyone. I have been to this site a few times in the past but this is my first time posting.

I am in need of some help, pointers, tips, guidance. I have a Larken 24x24 cnc router and Autodesk autosketch that I have used for 10 years, up to this point everyhing that I have done with it has been 2d. Now I am wanting to try to make a 3d mold out of wood. (basically similar to sign making)

This is where I feel a little stupid, as I feel that I am pretty decent and quick at designing things for 2d. That said, I am having a hard time even knowing where to start on this project.

After some searching and looking, I have not found anything to help get me started on this 3d project. Keep in mind that I have learned everything to this point by myself. No training or schooling. Someone please steer me in the right direction.

[bobsch]

Check this thread from microcarve: My Newest Desktop machineespecially the second page.

[DW1]

Thanks for the link, some very cool and interesting stuff.

My biggest hurdle right now is even knowing how to draw the mold in 3d, this is completely new for me.

[yohudi]

Thanks for the link, some very cool and interesting stuff.

My biggest hurdle right now is even knowing how to draw the mold in 3d, this is completely new for me.

Hi There,

Making a 3D mold is not so different to making a 3D model. The only real difference is the direction of the displacement applied to faces in the mesh used to generate gCode.

With this in mind I suggest downloading the cnc4free.org ebook on the tutorial page at http://cnc4free.org

Chapter 2 Describes the process of heightmapping a 2D image into a form that can generate a 3D mesh in great detail. Chapter 6 covers how to get from heightmapped image to mesh. Once you can do this it's simply a matter of inverting the image colour values so that faces displace inwards as opposed to outwards. I would also stress that you DON'T need to spend ANY money to acheive this. FREE software is capable of excellent results when applied correctly.

Regardless of the software used to generate the mesh or the toolpath, the MOST important aspect of the process is the correct application of heightmapping to obtain the desired effect. The images below show an 'artisic' style application but 'parts' type output is created in the same way. If anything it's actually easier to make 'parts' type output.

Hope this helps.

Danny (aka Yohudi)