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Dave Jackson
09-06-2006, 08:16 AM
I do a display in the front yard every year, expanding as finances permit. Over the past few years, I have purchased styrofoam tombstones for a graveyeard section, and last year decided to get a couple of the larger, more ornate ones for the back row.

Unfortunately, bad winds caused a few to topple, and one of the larger (more expensive) stones fell into the stakes for another and took a small chunk off.

Is there a way to coat the tombstone to make it harder and less prone to damage? I have heard that some chemicals will actually melt the styrofoam so I'm a little cautious on this.

Thanks for any help you can give!

screamlinestudios
09-06-2006, 09:29 AM
Coat the stones with a latex paint first to seal them, then coat them with a polyester/fiberglass resin.

Or simply coat them in liquid latex, a few layers will do.

Of course you'll have to repaint them afterwards no matter which method you use.

Good luck!

Dave Jackson
09-06-2006, 06:44 PM
Thanks for the tip. Right now I have around 25 tombstones, so the process may become extremely lengthy AND messy.

I went to a local hobby shop, and one of the workers suggested a can of Krylon Matte Finish. It was in with the paints, and is supposed to be a clear coating. If it works, I could conceivably use that as a protectant, then use something to harden it further without worrying about having to re-paint.

Yes? No? Just trying to think of easier ways.

Greg Chrise
09-06-2006, 09:28 PM
Any acrylic clear coat short of artist quality brush on clear coats (which would prove expensive) are too thin and putting a solvent based product over it will risk burn through. Good old latex paint brushed on or applied heavy with spraying is the way to go.

You arn't supposed to but, I have sprayed tombstones with latex paint through an automotive spray gun then cleaned it up good with solvent. It is best to just brush it on with a dark color as your base.

Using fiberglass resin as a hard coat can shatter like glass once cured but, things like 2 part polyurethane like what you would pour over a decorated table top are more elastic and less caustic to handle. It can also be tinted if you desire with universal paint tints and be the final finish.

The krylon if put on too thick (trying to make it do something) will not cure properly and remain sticky forever and cloud up blocking the possible under finish of any work.

If you want to go to pro level finishes, flatners are available for automotive clear coats these days which happen to work in anything, any medium. They are dry powders like pearls.

With styrofoam I would stay away from anything in a spray can even if it is supposed to be acrylic. These have solvents in them just to stay mixed and dispense with air without clogging. Unless of course you want it to be eaten. Sometimes wrong is the look you are going for.

Tattoo
09-07-2006, 06:56 AM
We have a new method that we have been using that has worked extremely well. (Note, this happens before paint is applied) When we make bricks, headstones, block, and trim, we take a sanding rasp and lightly "sand" the styro. You can then put on a glove and rub off any excess pieces of foam or dust. We then take a heat gun and quickly melt the sanded surface. The styro creates its own shell that is very strong and has stood up to alot of customer abuse. It's similar to the acetone process we use without having to deal with chemicals, gloves, spray bottles etc.

http://www.paleeye.com/product_info.php?manufacturers_id=1&products_id=1&osCsid=dd2c9ef9a7718c9d88570131e15635df

Take care,

Tattoo

jerzeydevil
09-07-2006, 10:07 AM
sometimes I spray them with water then toarch them lightly it seems you change the properties by doing this making them a bit harder, also try using paint stirrers to stake them in the ground then the stick will break BEFORE the tombstone. hope this helps.

Greg Chrise
09-07-2006, 10:09 AM
Oh, Now that's not a new method...That's one you guys have been developing for years that is BOSS and totally rules! And offering your wisdom in seminars like the cool people you are. Thanks Bad Boys!

actiondeath
09-09-2006, 03:24 AM
I know that you can mix concrete adhesive with quickcrete and smear it onto styro to give it a rough stoney texture and a hard shell all in one shot. It is the right color for tombstones, and it will also make them a bit heavier.

We purchased a facade this year with two large foam "brick" walls done up this way. The guy said he used a router to make the lines and just smeared the concrete mixture on. Once it dried, it was ready for paint. We have large boulders too. Very realistic looking and solid. He gave us the exact combination of what to use in case we needed to do any repairs, but I don't have it with me.

bhays
09-09-2006, 07:07 AM
I know that you can mix concrete adhesive with quickcrete and smear it onto styro to give it a rough stoney texture and a hard shell all in one shot. It is the right color for tombstones, and it will also make them a bit heavier.

We purchased a facade this year with two large foam "brick" walls done up this way. The guy said he used a router to make the lines and just smeared the concrete mixture on. Once it dried, it was ready for paint. We have large boulders too. Very realistic looking and solid. He gave us the exact combination of what to use in case we needed to do any repairs, but I don't have it with me.

Please post the exact formula...would like to have it.

Greg Chrise
09-09-2006, 07:44 PM
There are two food groups in concrete additives or admixtures. One smells like Elmers Glue as it is a version of it called aliphatic resin. This is cheapest as well and is usually cut 50/50 with water. You apply a bond coat of this liquid to the surface first, allow it to dry then apply your mix.

Usually the mix is any sand and concrete in a 2 parts sand one part portland cement mix. This can be grey portland cement or white. The sand is up to you how griity or floury you desire. This material white ot grey can be tinted with universal tints.

If you combine rough surfaces left by a heat gun shaping rocks and such and do this additional floating as well you really have something. The styrofoam full sheet should be supported by some plywood or other wood sheeting as the weight and deeper depressions make handling large sections kind of risky if a wind comes through. If it does break when handling even before completion, just glue it back together with exterior carpenters glue.

The second food group would be the admixture known as acrylic resin in varied degrees of cost and grade. Our tests show that if impacted this resin alone in concrete peels off of a damged spot on styrofoam and around whereas the aliphatic version only loses a chunk at the damaged area. This test was performed by whacking completely through a sheet of styrofoam with a hammer and observing which results were desirable.

You can put the resin type mixture over an aliphatic mixture base and most proffesional stone castings do this in reverse in a form mold or apply several layers of each and carve for a desired effect.

The sands available in the quick crete line are a bit too pebbly and red tinted for my taste. I prefer the sakrete all purpose sand as it is non tinting and can be filtered through a screen if all pebbles are desired to be gone and you still have a decent amount of sand left.

Super pro level formulas would use silica flour, a white sand milled to a flour already combined with white portland cement. It shouldn't cost any more than $12.50 for 50 # bag. You may find it at specialty concrete stores but be aware of big mark ups. For small quantities you might expect to pay $16.50 per 50 # bag. This would be floor overlay, stamping or texture material for concrete surfaces and can be used in either acrylic of aliphatic formulas.

Recently I ran into some concrete overlay guys. The young forman told me they use aliphatic compounds and on occasion had taken gallons of elmer's glue and mixed it with water. Well I tried it and it worked. In fact it proved to be very cost effective! A gallon of white elmers if you can find it is $10 and makes more like 4 gallons of which you would use 1.25 gallons per 50# of material. It took a longer time to set up than regular concrete formulas but ended up being pretty tough. Five gallons of Aliphatic admixture costs $52 or $10 a gallon. This Elmers trick ends up costing $2.5 per gallon plus the $60 in gas it takes to find a gallon of White Elmer's glue.

Any of these concrete mixtures would have some kind of sealent applied to maintian adhesion over a long period of time and remain color fast. You can do all of your washes with acrylic paint and then seal it with any clear that does not react with styrofoam but all of our latest experiments have had no clear and are holding up for years out doors. Eventually they will return to snot without a clear coat or sealer of paint but, it might be 12 years down the line before these effects are observed.