styrofoam

[frank taylor]

hi all
i would like to try a carving using styrofoam how do you clamp it to table if its a deep carving where do you get the long tool bits from keen on making it look like bronze statues any info would be great

[ozymax]

I had a similar problem just the other day.
I was carving out some pockets in a 3 inch block of foam for a packaging support.
I wound up just driving a nail into the end of a piece of wood. Cut the head off it and ground it to a sharp point.
Then simply speared the nail into the waste section of the foam block, did that at 3 other points around the block and then held them down with my normal clamps.
Syrofoam doesn't need a massive amount of hold down force, becasuse it offers little resistance to the cutter.
You may even get away with just using double sided tape or a few dabs of glue to a base board.

Can't help with the longer bits.
Maybe try slicing the model and using your nornal length bits.

[mikeacg]

Frank,

I have done quite a bit of foam but I never cut anything deeper than 2" (thickest I can get at the lumberyard). I slice the model and nest the pieces as well as I can since I am limited to 25x36 on my Stinger 1. I put a couple of pieces of carpet tape in the middle of the table and just screw the foam down with deck screws around the edge (You can pull them down into the foam and it is very secure). I got a couple of Freud bits off of Amazon for roughing so I could use thicker foam but it's just as easy to assemble 2" pieces as thicker ones and doesn't require special bits to account for the thickness. I have a 3/4" bit with a 2" CL that works great since I leave a 1/8" 'onion skin' to hold the pieces in place (very easy to sand off after assembling). I glue up with PL ### (It is made for gluing foam) and I toenail toothpicks to hold it in place until it dries.

Little Jerry was 6 layers of 2" foam...

Hope that helps!

Mike

[frank taylor]

thank you ozymax the nail,s in wood to clamp think i will go that way
mikeacg me two limited hight will go with slice option your Little Jerry did you paint with acrylic paint have you done any to give aged bronze look ????

[mikeacg]

Frank,

I used sign paint on little Jerry so he is totally weatherproof (look at my posts for the outside of my shop with the palm trees and toucan. They have survived several years of UP weather with no signs of degradation!)

I haven't broken down and gotten any Sculpt Nouveau yet but I have a couple projects that are screaming out for brass coatings...

Mike

[dwilli9013]

Frank,

I have done quite a bit of foam but I never cut anything deeper than 2" (thickest I can get at the lumberyard). I slice the model and nest the pieces as well as I can since I am limited to 25x36 on my Stinger 1. I put a couple of pieces of carpet tape in the middle of the table and just screw the foam down with deck screws around the edge (You can pull them down into the foam and it is very secure). I got a couple of Freud bits off of Amazon for roughing so I could use thicker foam but it's just as easy to assemble 2" pieces as thicker ones and doesn't require special bits to account for the thickness. I have a 3/4" bit with a 2" CL that works great since I leave a 1/8" 'onion skin' to hold the pieces in place (very easy to sand off after assembling). I glue up with PL ### (It is made for gluing foam) and I toenail toothpicks to hold it in place until it dries.

Little Jerry was 6 layers of 2" foam...

Hope that helps!

Mike

Great looking work Frank. Can you share what type of foam you are using? I would like to give this a go with some smaller pieces no larger that 16" x 18" x 2" thick. I have not tried foam as yet but your pieces intrigue me.
Beautiful work. Thanks for sharing.

[adze_cnc]

where do you get the long tool bits from

By "styrofoam" I'm going to presume that you mean extruded polystyrene (EPS) of the same sort used for wall insulation.

For that I've had great success with Onsrud (other manufacturers probably make similar) foam cutting bits; in particular 52-574 (3/8" dia 5" OAL, 3.5" CEL) and 52-564 (1/4" dia 4" OAL, 2.25" CEL). Both can easily do 240+ inches per minute (5hp spindle) at 1 to 2x dia depth of cut giving a smooth finish---deeper if you don't mind rough edges.

For profile cuts I find a last pass allowance of 0.02" conventional direction of cut gives a nice clean edge. The edge does degrade a bit at 3 and 4 inches deep though.

Steven

4-inch EPS cut with foam bit

[Mike-S]

This is two 2" pieces of foam insulation (Home Depot) glued together. I put a groove 1/2" above the bottom and used my "tongue and groove" hold downs. Cut with a 4" Burchett BN.

[frank taylor]

hi dwilli9013
they are not my designs they were done by mikeacg best you ask him

[dwilli9013]

hi dwilli9013
they are not my designs they were done by mikeacg best you ask him

Thanks Frank my bad

[dwilli9013]

Great looking work Mike. Can you share what type of foam you are using? I would like to give this a go with some smaller pieces no larger that 16" x 18" x 2" thick. I have not tried foam as yet but your pieces intrigue me.
Beautiful work. Thanks for sharing.
Sorry I posted this to the wrong person in error the first time.

[Kayvon]

How messy it this stuff? I've been interested in trying it, but I have no dust collection system in my garage, so I could see the foam flakes going everywhere.

Cutting HDPE was an adventure in that respect.

[Mike-S]

I checked and it's called "Extruded Polystyrene Insulation Board" from Lowes. You want the UNscored kind. Scored has length-wise slits for easier installation between studs. Since it's foam, it can be milled full depth in one pass.

You need a dust collection system to mill this. It make a snow storm and the chips are slightly static charged, so they stick to everything.

[jhowelb]

To fasten foam to the table, try this.....
Put down strips of masking tape on the table at least on the perimeter of the part.
Put matching strips of tape on the bottom of the foam.
Add tape on both to account for any cut outs.
Use 2P-10 (or other 2 part "superglue") to stick the tape together back to back.
Do your carving and then simply pull the tape loose.
No clamps to collide with, no distortion or compression of the part.

Enjoy!!

[mikeacg]

Sorry for taking so long to get back here (but I have a new machine in the shop and need to get up to speed!!).

I use blue insulation foam from my local lumberyard (I'm in the middle of nowhere so I make do with what I can get locally with no delivery costs). I started with foam just to test a project out before I wasted some really nice hardwood. I don't use any special bits as I didn't want to spend a lot of money just to find out if foam would work. It works fantastic with standard bits and I can run the machine really FAST! Not sure how the surface compares to using special bits like Steven suggested but I tend to do some further finishing to pieces when I pull them off the machine so it's not an issue for me. Let me know if any of you uses the foam cutting bits. Might be time for me to upgrade.

A coat of exterior primer and you can use spray paint without it eating away at the foam (That's how I painted the toucan). Or you can use the 'eating' to your advantage like I did on the anchor. I sprayed it, let it work for a few minutes and then hit it with water to stop the process. Gave me a great corroded look!

Yes, it is dirty as heck to run! I have my machine fully enclosed to cut down on that but it still sneaks into the house.

Mike