20 sided dice

[foamcarver]

We have a job that our customer wants a 20 sided die. We are running into some problems figuring out how to cut it. We are cutting it out of foam and we won't be cutting it on the shopbot, it's going to be cut on our foam cutter (you can see our foam cutter at foamcarver.com) Has anyone ever cut this before or something like it?

Thanks in advance for your help

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

[hippo]

You're going to have to do a little math I think.

In the meantime, I would get your block of foam, and cut the flats vertically rotating it each time, and when those are cut, then lay it in turn on each of the flats that you cut previously and continue until you have cut all the sides. You're going to have to make a lot of cuts, but they're all straight lines, so it shouldn't be too bad. The key will be that you've got to turn the foam or your cutter won't be able to get at all the sides,

Of course reading that I'm not sure it makes any sense, but it was worth a try.

-Dan

[bill.young]

Hey Mark,

An Icosohedron is a 20 sided solid with triangular faces...is this what they want (outside link to wikipedia article) (http://en.wikipedia.org/wiki/Icosahedron)? I just made a dome for my wife's class at school that's based on an Icosohedron...there's a picture on this forum thread. (http://www.talkshopbot.com/forum/show.cgi?tpc=2&post=44905#POST44905)

If that's what you're looking for I can give you the face angles, but instead of cutting it as a solid can you cut it as a pile of seperate triangles and glue them together? Would probably be easier than trying to rotate and index a big solid.

Bill

[jseiler]

http://en.wikibooks.org/wiki/Blender_3D:_Noob_to_Pro/Die_Easy

Maybe you can get a good model in blender and 3d cut it

[rnels]

Nikki,

Hope you paid attention in Geometry class! I know it's over my head. Here's a link to a guy who makes these in wood but looks like he's a math genius as well.

http://www.georgehart.com/virtual-polyhedra/wooden-models.html

Also a site that makes these foam dice:

http://www.rpgshop.com/product_info.php?products_id=38530

I remember seeing your foam cutting machine at the Camp but can't remember how you cut multiple sides like this.

Good Luck

Randy

[foamcarver]

Thanks for all your help. Bill we thought of doing that, but our customer wants it solid as possible on the inside. but that is really a neat idea. Nope don't know geometry real well. But I think we're finally on the right track. If you look at the 20 sided die, you can turn it any way and have 5 sides pointed the same way. We we did a sample one where we cut 3 5 sided pyramids and put them together. Now we just have to figure out how to put the last pieces together. two triangles on opposite sides look like we'll be able to cut one long piece to go all the way through, which will help to support the die. Hopefully it will all work the way it's supposed to. Anyone have any ideas on what to coat it with--they want it to be kind of a rubbery texture. We thought about that stuff you can dip the handles of tools in, but they come in such small bottles. Any other ideas.

Thanks for all your advice and ideas.


Thanks again

Nikki

[oddcoach]

how big does it have to be? i can give you a 3d file of one that you could use 3d carve to make it in slices and glue together

[rick_woodward]

Nikki
it seems to me i heard foam people using rhino truck bed liner spray. Dont know if its rubbery enough for them. But it would be tough i'd think. rick

[foamcarver]

The dice is 5ft by 5ft. So it's pretty big. We'll have to look into the rhino spray stuff.


Thanks
Nikki

[jhicks]

Mark, you can look into the liquid PVC that is used for molds and costume masks etc. I think its a simple brush on material. I have an old quart bottle here manufactured by I.S.L.E. Labratories but cant find them on the web.
here is one that may be useful though.
Just not sure about heating to cure it?
http://www.mpcltd.ca/plastisol.html
This one is quite strange in their choice of application and market but it just may be the right stuff.You'll know what I mean when you check it out.
http://www.liquidlatex.com/

[frank_hav]

Mark, We use truck bed liner on alot of our touring speakers. I can tell you it's not rubbery per say. It is also not going to protect the shape from being dented, if thats what they are looking for. Liner applied to a soft surface is like your shoe protecting your foot. It stops minor contact but if you hit hard enough it still feels it.

Frank

[foamcarver]

Thanks for all your ideas. But thankfully our client is going to do the coating. We are sending it out to them this afternoon. I'll post some pictures of the massive dice.

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

[foamcarver]

8670
8671

[jhicks]

"Rolling the dice" taks on a whole new meaning when I see these babys.
Cool work.

[baltic_birch]

"Mark, We use truck bed liner on alot of our touring speakers. I can tell you it's not rubbery per say. It is also not going to protect the shape from being dented, if thats what they are looking for. Liner applied to a soft surface is like your shoe protecting your foot. It stops minor contact but if you hit hard enough it still feels it.

Frank"



Say Frank,

Could you walk us through the process?
Or do you have it outsourced?

I tried a the can of roll/brush on ....rhino??
It was expensive for a gallon $50-70.

Anyway, it did not cover the grain of wood or the joint lines...... just curious what brand/type/application methods you use.


Thanks!