'Dow" styro or EPS HELP

[jessieb]

Hi, everyone!
I've been checking out this website for awhile now and have found myself in a desperate situation and need some advice: I have a rush order for a T-Rex sculpture and I need to decide whether I can use regular DOW brand styrofoam (they call it expanded polystyrene but I thought that's what EPS stood for!!!) (I have kazzilions of 2 foot x 3foot x four inch sheets of green Styrofoam in stock (for big Floral work we do).
I don't have any "EPS" on hand and have never bought it before; I've found some suppliers in the Cincy area that have it but I have no idea what density to buy! They have 1#, 1.5# and 2# density. The 1.5# comes in 40" x 48" x 96" blocks and runs close to $400.00
The T-Rex will be covered in natural Sheet Moss, so final finishing isn't the issue - I do think a hard coating will haelp keep the item stable; I think the styro I have is to brittle.
All the different advice about foams and coatings has me kind of confused! Can I put a Urethane coating right on styrofoam.
It will be in a rearing up ('kinda Godzilla like') and will be approx. 7' tall, 9' long. It will be installed onto a 2' diameter, 5' tall(!!!) pedestal. (There will be a circular couch built around the pedestal.
This item is for a one night rooftop party BUT it's GOT to be great, strong and stable (and I can probably bring it back with me and re-cyle the carving if I never need to make a mold or something like that. It also needs to ride 700 miles in the back of a pick-up.
Can anyone respond with some advice?
Thanks!!!
.

[jessieb]

I realized something - the 'styrofoam' i have in stock is extruded polystyrene (I should have known this)

[Arrow]

Post pictures of the process if you can, please. Sounds like a fun project.

Hard coat for foam:
http://www.industrialpolymers.com/styrospray.html

[obseq]

The absolute cheapest means of sculpting from foam is to head to local construction sites and ask for leftover sheets of blue or pink foam.

Both the blue and pink foam brands are a high-density EPS that is suitable for sculpting. Whether you find blue or pink is entirely dependent on your region. Blue is usually found in the West, while pink is found in the East.

You can glue the sheets together and improvise 'blocks' with 3M Super 80 which is the least corrosive adhesive I have been able to find for foam. The process is long and fairly annoying, but outside the cost of the 3M Super 80-- It is free.

I see that you mentioned coating in urethane-- My guess is that it would eat right through the foam, so you'll have to engage in some trial and error to see which products are safe for the foam. Most products declare that they are safe for use on foam, but oftentimes, this isn't the case.

Good luck and do keep us posted!

[jessieb]

Thanks!
I'll post some pics (if I can figure out how do do that quickly!)
I found a company that does CAD EPS carvings (theme park stuff, etc) within 90 miles of me; I sent them my drawings and designa nd they rough-cut my shape out of a 4x4x8 block of EPS 1.5# density.
Just got it late last night - we have about 1½ days to get it mounted to a metal plate base, completely carved, coated, strengthened -
I'm still tring to figure out the best, quickest, strongest final; coating process - because this item is going up in the air (rooftop) I want to make sure it would break at any weak/stree points!
I may use fiberglass tape (I hear it's aweful to work with) and I can use the 2 part epoxy coating instead of resin which is more toxic...
any suggestions?
I may send this thread over to construction techniques also to see who's around that might have some advice.
Thanks all!!