Dinosaur help

[nepenthes]

I have just started playing around doing 3D carving with our 'Bot and now find myself presented with a great project helping to make 3 life sized dinos! They will have steel armatures, foam bodies and then finished in epoxy clay. My job will be cutting the foam with the 'Bot. I need some suggestions on bits, stepover and speed. Currently I am planning on using 3" foam. Here is a small sample head I made using 2" foam.

http://i141.photobucket.com/albums/r63/nepenthes1/0403080837.jpg

http://i141.photobucket.com/albums/r63/nepenthes1/0401080925.jpg

Any suggestions would be greatly appreciated. This is quite a project for me. The largest dino will be 29' long!

[Brady Watson]

Full 3D with arms and legs presents the 'undercut' problem, which you can address by breaking the Dino into separate components. You may have to break some things into several sub-components so that they will fit within the XY extents of your material & machine. Separate the head from the neck, the legs and tail from the main body in software & save it out as a 3DS, STL, OBJ or 3D DXF. Then you can bring each piece into either Cut3D or PartWorks3D and when you setup your material, choose 2-sided, set thickness at 3", adjust your centerline if necessary, then click on 'Slice Model'. This will slice the model into 3" thicknesses that can be machined on the Bot. When all is said & done, just glue & stack them up to get the full 3D model. Ways for steel to go into the foam are best handled with a hot knife or by hand cutting.

-B

[kfitz]

I carved a 6' tall Velociraptor some years ago. With the size you are talking about, you will be making a mountain of mess.

1. Wear a respirator
2. Wear fully sealed goggle-type eye protection.
3. Manually follow the cutter 100% of the time with a really large capacity dust collector.
4. I used a long-shank 1/2" ball nose two-flute bit. Run it slow RPM with a high feed rate. I glued up 3 layers of 2" foam. Had to modify the z-zero routine to give me enough z.

The foam beads will pack onto the rails like steel. Keep the rails clean. Good luck.

[chiloquinruss]

When doing foam stacks I use shishkabob wooden skewers to hold the pieces while the glue dries. I also use a Stanley Shurform rasp for major cleanup stuff!
Russ
http://ecx.images-amazon.com/images/I/31xFcSbVY-L._SL500_AA160_.gif

[kfitz]

If I remember correctly, cutting time was 5 hours. As you can see, stepover was quite large and left lots of ridges. However, some 80 grit sandpaper made short work of the texture. More efficient than smaller stepover, I think. By the way, these foam parts were made for a museum. They used them as male plugs to produce a female mold. As Brady noted above, the appendages had to be cut seperately.
7985

[nepenthes]

Thanks for all of the suggestions! The job is looking more and more likely, which makes for the dream job of a lifetime!

[nepenthes]

As I am going through and cutting slices for my estimating, many of them are fairly small. Is it possible to nest the small pieces together using Cut3D or some other program?

[Brady Watson]

No. You are limited to the slice material XY dimensions, unfortunately.

-B

[gene]

kevin
What program did you create the dino in? I am wanting to play with stuff like this . Any help or steering in a right direction would be appreciated.. Is there a program you can import a flat drawing into and make it 3 d like this ??

[Brian Moran]

quote:
As I am going through and cutting slices for my estimating, many of them are fairly small. Is it possible to nest the small pieces together using Cut3D or some other program?

If you have Cut3D and VCarve Pro (or PartWorks/ PartWorks3D) you can calculate the toolpaths for the small slices in Cut3D / PartWorks3D and then import the v3m files with the toolpaths into a new job in VCarvePro / PartWorks and manually nest the toolpaths on a larger sheet.

Brian

[kfitz]

Gene,
I purchased a 3D model from www.turbosquid.com (http://www.turbosquid.com) . I then sliced it and diced it in Rhino. Toolpathing was done in Freemill.

[foamcarver]

Michael- I just wanted to make sure you got my email yesterday. I would be glad to give you tips on how we handled the undercuts and other problems we ran into along the way. Our phone number is 651-778-2950

Thanks
Nikki
nicole@foamcarver.com (mailto:nicole@foamcarver.com)

[nepenthes]

Message received. Thanks. I will give you a call in the next couple of days.