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cnc_fabricator11
04-19-2012, 04:06 PM
I've found a few threads similar to what I'm looking for, but I wanted to ask specifically for my application. I have a 3D surface that will ultimately be a wall panel that I carved with my PRS Alpha out of blue extruded foam (insulation foam). I was wondering if you had suggestions for products that I could coat the surface of this type of foam with to make it hard and wouldn't eat away the foam? I'd appreciate any info.


Thanks,

-Patrick

billp
04-19-2012, 04:24 PM
Patrick,
Apoxie, is one product- http://www.avesstudio.com/index.php?page=shop.product_details&product_id=28&flypage=flypage.tpl&pop=0&option=com_virtuemart&Itemid=4&vmcchk=1&Itemid=4
Another one is Magic sculp- http://www.magicsculp.com/

cnc_fabricator11
04-19-2012, 04:57 PM
Bill,

Is this Apoxie Sculpt ideal/economical for entire wall panels? I see it being used on models, figurines, statues. I'm going for the semi-gloss or gloss look of fiberglass on this foam.


Thanks for the input,

-Patrick

billp
04-19-2012, 05:04 PM
Patrick,
Depends on how you judge economical. When you consider the effort usually involved in hard coating large parts I think any product that can be applied quickly, and without extra equipment IS economical. Once you have your part coated you can then use ANY type of finish you choose (even solvent based since you now have a "barrier coat").
Your initial choice of styrofoam means that you will HAVE to make some concessions, but not many, in order to get the effect you are looking for.
There are many posts on this topic which can be found in the archives using the search engine, but I think you will find that for the most part people have eliminated MANY of the more 'commercial' coatings ( ie Styrospray, etc.) because of their tendencies to 'slump/sag"etc. The two I mentioned earlier can be hand rubbed onto the object in question, and they will stay in place.

COBOB
04-19-2012, 08:33 PM
I really do not know if this stuff will help you. I haven't tried it yet but intend to soon. I just got this in email the other day. Watch the YouTube video. Looks good to me.

http://hotwirefoamfactory.com/-024-GAL-Styroplast-gallon.html

joe
04-19-2012, 09:46 PM
If anyone gives this material a try, I'd sure like to hear about it. I've lost a considerable amount of money with Styrospray. It doesn't get hard and always stays flexable.

Joe Crumley

cnc_fabricator11
04-20-2012, 09:30 AM
Thanks for the responses. I'm going to order these and test them out. I'll let you know what the results are.



Thanks again,

-Patrick

billp
04-20-2012, 10:44 AM
Patrick,
Here is one method that DOES work. You start with a WATER based primer ( like Zinzer WB) to fill in the 'pores"of the styrofoam. Then with your barrier coat in place you can top coat the object with an epoxy ( I am a long time fan of the MAS product because of it's low VOC content, ease of sanding, and vinegar cleanup).

joe
04-21-2012, 11:59 PM
What all of us have been wanting is a surface coat that's as hard as Peachtree Signs have. They use a Plural Spray system. It's thirty thousand expensive and down right dangerous. You can up them one by using a first surface material like HDU, Trupan, Extira or PVC. With these materials you have the opportunity of to show off your router skills. That's what I've been doing for a couple of years. Peachtree signs loose detail something awful.

Why not go this direction and forget all the tough hardcoat things.

http://i38.photobucket.com/albums/e115/jcrumley1/1-Magnusson-sign-on-floor-front-view.jpg

http://i38.photobucket.com/albums/e115/jcrumley1/Regional-Physical-Ground-Sign-1.jpg

http://i38.photobucket.com/albums/e115/jcrumley1/IMG_1805.jpg

All sides, front and back, top and bottom are hard surfaces. Only the interior is EPS foam. Make it easy on your self.

Joe Crumley
www.normansignco.com

sailfl
04-22-2012, 06:06 AM
Bill

Have you actually used StyroSpray?