Blue Foam?

Got a question about techniques, materials or other aspects of physically building a model? This is the place to ask.

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Dr. Yo
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Blue Foam?

Post by Dr. Yo »

I started my first two projects with blue insulation foam over the
weekend, a Khorzvell frigate, and my 'long rifle' for the SSC small
arms challnge. I figured there'd be an article in the archives, but
didn't find anything.

What I know so far-DON'T use cyanoacrelate on it-yikes! ( I don't know if it produces any dangerous fumes or not, I only used a drop, but whoa!)

It sands wonderfully and is very easy to sculpt, if you're patient, and have
a very sharp blade. I'd appreciate any other tips those of your with
more experience would care to share. I'm guessing that epoxy would be
good for laminating larger sections. I'm also remembering when this topic
came up at some point in the recent past, there was some discussion of
what type of resin was compatible with this and fiberglass, but I don't
remember much other than that...
"Semper fiendish"-Wen Yo
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Jonas Calhoun
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Post by Jonas Calhoun »

I've used both the blue and pink foams in building nosecones for my larger rockets.

A few tips:

Get a hot wire cutter. Either build or buy, but they are invaluable when carving large sections. Google around, there are plans to make one, or Woodland scenics makes one.

I've laminated fiberglass cloth without any trouble. Use a slow cure thin epoxy, the heat of the faster curing ones can damage the foam. I've then used solvents to get the foam out of there--acetone, mostly. I've also laminated sections together with the epoxy. Put a couple of encyclopedias on top, enough to clamp the pieces together, and no warping.

If you want to paint it, put an acrylic or latex primer down first. On some of my large sections, I thinned down housepaint, and sprayed that on. Solvent based paint will attack foam.

I've also put a dowel as a center of a foam block, chucked it into a drill, and then used that as a makeshift lathe. Sandpaper works fine for carving when it's spinning--do it outside, it really makes a mess though. Wear a respirator (I also had Tyvek painting coveralls on).

Hope this helps,
Dan
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Dr. Yo
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Post by Dr. Yo »

It does indeed-thanks, Dan.

The tip about thinned housepaint is very timely-I'm going to be painting the house in the weeks ahead ( We had new siding put on a while back...)

Is there a particular 'slow cure, thin epoxy' that you'd reccomend?
"Semper fiendish"-Wen Yo
Scott Hasty
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Post by Scott Hasty »

Jonas Calhoun wrote:
If you want to paint it, put an acrylic or latex primer down first. On some of my large sections, I thinned down housepaint, and sprayed that on. Solvent based paint will attack foam.
I just used a Krylon product called H2O. It's a latex based spray paint [soap and water clean-up]. Stuff is awesome and dries FAST. $3.77 at Wal Mart.

Scottie
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Dr. Yo
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Post by Dr. Yo »

Just read about that stuff in R.Pink's 'Painting over EPP foam thread'
Sounds promising as well-thanks Scott.
"Semper fiendish"-Wen Yo
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Post by Kylwell »

Been reading on the web about EEP and it seems that there are a few different types. Was reading on some RC aircraft baords about regualr rattle-can paint melting it, other places where nothing can touch it.

Other than that, EPP sounds like a dream.
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Jonas Calhoun
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Post by Jonas Calhoun »

Dr. Yo wrote: Is there a particular 'slow cure, thin epoxy' that you'd reccomend?
Depends on how much you want. Last time I bought epoxy was from West Marine, but I bought 3 gallons of it. Expensive that way (about $80 a gal), but it comes with measuring pumps. It isn't a one-to-one ratio though. Check a composites supply store near you, I've used a company called CMI (Composites Materials Supply IIRC) to get epoxy, carbon fiber, kevlar, milled fiberglass, press-n-ply, etc.

If you arn't needing too much, Z-Poxy is pretty good. Stay away from the Bob Smith stuff. Normally excellent stuff, but for this app, it's just too thick. You want stuff that's like warm maple syrup if you are laminating cloth. You can go up to molasses viscosity of you are just gluing panels together.

If you are putting cloth down, I've got lots of tips--let me know.

Dan
"Laugh while you can, monkey boy!" -- Lord John Whorfin
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Joseph C. Brown
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Post by Joseph C. Brown »

Here's a few thoughts on the topic; click to download!
.....

but, since I double-posted, try the next entry. Move along, nuthin' to see here....
Last edited by Joseph C. Brown on Thu Apr 28, 2005 9:56 pm, edited 2 times in total.
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Joseph C. Brown
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Post by Joseph C. Brown »

Here's a few thoughts on the topic; click to download!

Joe's WF Foam Class handout
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Dr. Yo
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Post by Dr. Yo »

Blink*Blink....Just printed it out, Joe-Thanks! I'll e-mail you some pictures
once I get a little further along.

Dan-I'll probably be getting back to you on the glass techniques as
well-thanks again, all of you.
"Semper fiendish"-Wen Yo
Keifer0999
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Re: Blue Foam?

Post by Keifer0999 »

Dr. Yo wrote:I started my first two projects with blue insulation foam over the
weekend, a Khorzvell frigate, and my 'long rifle' for the SSC small
arms challnge. I figured there'd be an article in the archives, but
didn't find anything.

What I know so far-DON'T use cyanoacrelate on it-yikes! ( I don't know if it produces any dangerous fumes or not, I only used a drop, but whoa!)

It sands wonderfully and is very easy to sculpt, if you're patient, and have
a very sharp blade. I'd appreciate any other tips those of your with
more experience would care to share. I'm guessing that epoxy would be
good for laminating larger sections. I'm also remembering when this topic
came up at some point in the recent past, there was some discussion of
what type of resin was compatible with this and fiberglass, but I don't
remember much other than that...

Do a search for hotwirefoamfactory for some tools.
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Joseph C. Brown
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Post by Joseph C. Brown »

My download class writeup covers hot wire tools, cheapie ones (actually a good deal, mostly) and the more advanced units, like HotWireFoam Factory's products.

There are foam-safe CA glues out there -- they are pricey, but, you really do get what you pay for:

Pacer's Zap-O, (price is for a bulk order!)
http://www.hobbylinc.com/htm/paa/paapt25.htm

and Horizon Hobby's 'E-Flite' Foam Compatible
CA glue.

I fell in love with how well the E-Flite works on foam!
________
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bluesman
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Post by bluesman »

Dr Yo,

I ahve had good results using a water based adhesive called Ultimate. It is non toxic and is good for attaching your foam shapes.

I have also sheeted styrene to foam using the same glue and making sure it was sealed up before paint. I layered epox which also works well.

You can also mix up some Apoxie Sculpt roll out secions (like a pie crust) and lay them onto foam shapes. Smooth out the amterial, let cure and and sand.


I was always afraid to scratch build curves and complex shapes, but with good drawings a hunk of foam and some patience you can build just about anything.
"The" Bluesman formerly known as The Bluesman
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Dr. Yo
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Post by Dr. Yo »

Thanks Bluesman-sounds like a viable alternative-who carries it?
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Post by bluesman »

Dr Yo

You can find Ultimate adhesive at www.CraftersPick.com


or you can get some from me if ya want. PM me.
"The" Bluesman formerly known as The Bluesman
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