The "official" word from Krylon

Surprised me that they responded so quick to my question on usuing Fusion paint on Plexiglass, but their rely was simply they do not have any products that are compatable with coating any plexi or lexans........They said the sovents and other ingredients will melt the material........or possibly discolor it.....Well if its painted so what if its discolored under the paint. I just sprayed the aquarium hood with a can of semi gloss black, in light coats, and once it was covered I laid on a wet coat......I experimented last night, and the stuff I painted you could not scrape it off with your fingernail this morning...Anyway project is done, just waiting for one more power compact light assembly to get here and it will be finished totally.

============================================== Put some color in your cheeks...garden naked! "The original frugal ponder" ~~~~ } ~~~~~~ } ~~~~~~~ }

Reply to
~Roy
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The problem you're likely to encounter is the inability of Plexiglas to resist the solvents. You often get considerable crazing, although I'm not sure if it would occur immediately, or in the near future. I've ruined Plexiglas that way in the distant past, but it likely depends on the solvent in question. If it's still intact in a couple days, showing no signs of cracking, looks to me like you beat the problem. Let us know.

Harold

Reply to
Harold and Susan Vordos

I don;t know what solvents or thinners Krylon uses, but it dries very fast, so hopefully it did evaporate readily before it altered the integrity of the plexi to any great extent..........I just have too much work in this hood, but I do feel confident it will be ok. I had quite a few light coats on it so evaporation was pretty quick.......although sometimes rapid evaporaton accelerates potential problems, but its usually in the form of the paints wrinkling etc........Anyway I feel pretty confident with it working.

If I had the $$ I owuld have bought solid colored black plexi and been done with it, but the distributor here will not cut a sheet of tinted or solid color plexi. They will cut clear but not colored. And I would have had to buy a sheet of 1/8, as well as 1/4". I have a barn full of all kinds of other colors, and a heap of clear and tinted I got for free in all sizes and thickness, as well as a heap of all kinds of polycarbonates, fiberglass, textures, nylon, and polyethlene type plastics........just begging to be made into something. My shop anymore looks like a snowstorm.......its been a summer long affair of making acrylic projects since I acquired all those sheets, and very little metal working projects.........

I have a few full sheets of bullet resist acrylic, (1" and 1 1/4" and some 3/4") I had wanted to use to make a large capacity aquarium out of but found out it does not solvent weld, and needs to be joined and attached with mechanical means, as solvents will cause it to delaminate.....Would have made a fine saltwater fish tank of unreal size.......Its amazing what large companies will throw out when they move, and not want to move or relocate it. The company I got all this plastic material from relocated to a larger building across the street from where they originally were at, and they threw out tons of perfectly good stuff..........

============================================== Put some color in your cheeks...garden naked! "The original frugal ponder" ~~~~ } ~~~~~~ } ~~~~~~~ }

Reply to
~Roy

There are extruded acrylics and cast acrylics. They seem to react different to solvents. If you polished the edges you might get more crazing. I have handled probably about an acre of acrylics over the years and used all sorts of solvents around it. The stuff is really quite resistant to anything except methylene chloride which is used to fuse the edges of cut sheets.

Reply to
daniel peterman

So make the fish tank with big rubber gaskets and some nice stainless steel fixtures to clamp the plexi to the gaskets.

Also the solvent bonding warning only applies to bonding the edges. If you were to bond to the face of the plastic it would be no different than bonding regular plexi.

I bet if you face bonded some square Plexiglas to the inside corners that might overcome the delaminating problems also.

Just a thought.

Reply to
Roger Shoaf

snip

I had thought about using a sealant and enclosing it all in a stainless fraame, just like the old time tanks were made prior to the advent of all glass with silicone seals.......

This is true, as long as I don;t apply solvent to the edges its fine to bond to on the face

I had also thought about this. I was thinking of making enought chamfered strips (like a rightangle triangle affair, with the two legs of the triangle being equal to at least the thickness of edges, and solvent weld it in the corners......Be double the normal amount of solvent welded seams overall, but it has a possibility. Having chamfered inside corners would make life a lot easier as well as corners are always a pain in a fish tank.....

thanks for your thoughts on this.

============================================== Put some color in your cheeks...garden naked! "The original frugal ponder" ~~~~ } ~~~~~~ } ~~~~~~~ }

Reply to
~Roy

Text this time...

Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder

daniel peterman wrote:

Reply to
Martin H. Eastburn

Dear Roy,

I have been using Plexiglas acrylic and Krylon paints, mostly their standard indoor/outdoor gloss enamel, for over twenty years with no incidence of what they warn you about. The Krylon solvent evaporates extremely quickly, being touch dry in only a few minutes. Once you have sanded down the surface with 220 wet and dry, you can first use a Krylon primer, preferably a sandable one, or apply the Gloss directly to the Plexiglas surface. I would guess that they are just covering their rear ends :-)

The extruded plex, 'MC' is a lot more likely to be crazed by solvents, but still should be okay for Krylon, but when in doubt sticl to plexiglas 'G'. Perhaps their new fusion paint, which is supposed to be for plastics, isn't as good as they hoped? richard in Los Angeles.

Reply to
rmedway

snipped-for-privacy@webtv.net (daniel peterman) wrote in news:22573-4347E1AC-300 @storefull-3337.bay.webtv.net:

I do know that acrylics do not work well around ethyl alcohol. I made a container from a cast acrylic tube for an experiment in which it came into contact with ethyl alcohol. A day after it was put into use the tube cracked all over and just fell apart. It was very "impressive".

I now check compatabilities before building anything.

Cole-Parmer's catalog or

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have good tables.

Also google "(material) chemical compatability".

Reply to
Ken Moffett

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