I have been cutting lots of HDU pieces on my ShopBot and recently some insulation foam sheets. I was told a long time ago that Jay Cook's primer works great on HDU so that's what I've been using for a few years. Now that I am using my CNC router, I have been cutting indoor signs, logos and shapes from insulation foam mainly for practice.
I want to paint the insulation foam pieces so I need to know what water-based primer will do the trick. Also is their something I can use to give the cheap foam a harder shell before painting?
Some of these projects will turn into Christmas presents if I get them done in time! Any suggestions would be appreciated. I did go out to the Sherwin Williams paint store and picked up a quart of their water-based primer to try. It isn't too expensive ($21.Gal) $10 for the quart. If it works I will go back and get a gallon. Anything else out there that you are using? Thanks for your help!
Sign-cerely, Steve
Posted by Rodger MacMunn (Member # 4316) on :
Steve, I used Jay Cooke's primer for years but bought a can of BM Fresh Start just for fun & I was hooked. It sands out much nicer ( doesn't ball up in the sandpaper ) & sooner, doesn't puddle up in the corners as badly & if you're rolling it, it doesn't splatter up your arm as much. The new BM "Superior Primer" I don't like as much.
Posted by Steve Luck (Member # 5292) on :
I am guessing BM stands for Benjamin Moore and not what I first thought Fresh Start was referring to? Thanks Rodger, I'll check and see who carries it around here. Maybe Lowes or Home Depot?
Sign-cerely, Steve
Posted by David Thompson (Member # 2395) on :
I have not tried it personally, but some modeling buddies swear by Durham's Rock Hard Water Putty for coating foam to get a hard finish.
[ December 20, 2012, 09:53 AM: Message edited by: David Thompson ]
Posted by Raymond Chapman (Member # 361) on :
HDU does not need a primer for a top coat paint to adhere. Almost anything will stick to it. But, some of us use a primer mainly to smooth everything out, but several coats of paint would do the same thing.
I use Coastal Enterprise's FSC88-WB primer (water based) because it dries quickly and sands to a super smooth finish. It can be sprayed, brushed or rolled.
I'm not familiar with the lighter foam materials, so not much advice can be given. It seems that the extra steps of applying a hard finish could be avoided by simply using a higher density HDU.
Posted by Preston McCall (Member # 351) on :
Durham's Rock Hard Putty literally is rock hard....very brittle. Not that that is a problem in most cases, but in making picture frames, I have found bondo works with much better expansion and contraction. Hard to get smooth, but at least it is flexible. Amazingly, it is still fairly inexpensive at 20-25 a gallon can. If you rough sand it fairly soon after it sets up, it can be easy to work, but wait a day and it is really hard.
If someone could add something to the Durham's to give it less brittleness, then that might help as the water based Durham's does hand form a bit easier with a damp cloth to smooth it out before it sets up. Maybe some fiberglass strands?
I have to think going back to a surfacing primer as used in a body shop would be better. Not up on the specific products today, but surely someone makes a water based surfacing primer that sands without balling up the paper and could be brushed on? Any ideas?
Posted by Douglas Hancock (Member # 29758) on :
Look up styrospray 1000 from www.industrialpolymers.com it is 2 part plastic that can create a gloss finish with brush application. They will sell a 2qt batch that can do I think 100 sqft for about $25.00. If you want to make it super smooth get the primer too. I have some but have not found the time to play with it. The samples I have look awesome. This is what all the prop guys use.
Posted by Steve Luck (Member # 5292) on :
That's great guys. Thanks for your suggestions. I do use HDU for project that will be outdoors or needs to be more rigid, but a 1" 4'x8' sheet of HDU is $206.00 and a 1" 4' x 8' sheet of insulation foam (pink or blue!) cost $15.87 at either Lowe's (blue) or Home Depot (pink).
I would only use insulation foam for interior projects anyway, but would like to give it some strength with a good primer or some sort of top coat along with the paint.
The Shopbot router cuts the insulation foam so smoothly and is really inexpensive to work with. My friend Doug haffner is making some "Amazing Creations" with it. He did suggest the Styrospray but also uses Sherwin Williams Concrete and Masonry primer. I still use Jay Cook's primer on lots of signs but wondered if it was ok for insulation foam. It works on everything else!
Another thing I was wondering about: What type of sprayer do you use and has anyone tried the cordless battery-powered sprayers? They are around $450. Just wondering if it's worth the money. Thanks.
Sign-cerely, Steve
Posted by Wayne Webb (Member # 1124) on :
I sometimes spray FSC88WB onto HDU, thinned with water, using an HVLP gun with an oversized 2.2mm nozzle. Never tried spraying Jay Cookes but when I did use Jay Cookes, I had problems with it 'balling up' in the sandpaper. I wet-sand the FSC88. Haven't primed any styro, but I understand it takes acrylic latex well.
Posted by Joy Kjer (Member # 3026) on :
Steve, on the pink foam insulation for interior, I have use Elmer's glue mixed with latex paint. It might do what you want for this application and talk about low tech!
Posted by Joy Kjer (Member # 3026) on :
Steve, on the pink foam insulation for interior, I have use Elmer's glue mixed with latex paint. It might do what you want for this application and talk about low tech!
Posted by Joy Kjer (Member # 3026) on :
Steve, on the pink foam insulation for interior, I have use Elmer's glue mixed with latex paint. It might do what you want for this application and talk about low tech and easy to find!
Posted by Dale Feicke (Member # 767) on :
Steve, I've been using Cover Stain by Zinsser lately.
It's thick, dries fast and sands easily. I made some finials for the top of some poles out of cheap styrofoam, and it worked great for them.
I think I got it at Lowe's.....but I'm not going to tell you 3 times!
Posted by Joy Kjer (Member # 3026) on :
Why does my post keep multiplying??? It started out as only one, really!
Posted by Rick Sacks (Member # 379) on :
Joy, acrylic paint and the white glue sounds like a wonderful idea!! I also heard that from Ron Percell.
[ December 22, 2012, 10:39 AM: Message edited by: Rick Sacks ]
Posted by Rusty Bradley (Member # 6938) on :
For fear that my post may be multiplied I've decided not to post.
Posted by Curtis hammond (Member # 2170) on :
quote:white glue
Is usually polyvinyl acetate latex.
Some white glue is made from clear acrylic.
Posted by Kevin Carlson (Member # 1283) on :
This is for stryrenhttp://www.fxsupply.com/steves/steves.html?PHPSESSID=fmc17lec6sc43piotg36nffmb2e
Posted by Dale Feicke (Member # 767) on :
Incidentally, I stated above that I was using Zinsser Cover Stain for primer on Styrofoam. It fills great, sands great, and takes paint like crazy.
Just in the last couple days, we also used it to block out some digitally printed RED copy on a VINYL banner. It stuck to the vinyl, blocked out the red, and the "patching" was invisible after we put the white acrylic topcoat on it. I was impressed!.
For anyone who might've used the old XIM white primer in past years, this stuff is almost identical to how that stuff smells, acts and works......but a good bit less expensive.
Posted by Curtis hammond (Member # 2170) on :
I use this Zinsser Cover Stain on every thing I make with MDF. It seals tight first time every time. But you have to work fast because it does build up.
![[Wink]](wink.gif)