Polycrylic

Woodworking is also a hobby of mine. Last year I finished a stereo cabinet with Minwax Polycrylic. After reading Godzilla's report on using it for model airplanes on the bare wood as a basecoat for paint I decided to try it. I could not get the lid off. The can was literally destroyed trying to remove it. After buying a new can and not using it for several days I experienced the same thing. It was like it was glued on. GLUED ON......hmm...I've used polyurethane glue to bond balsa skins to a foam core. I wonder what polycrylic would do. Last night I made up a small test sample, using polycrylic as a glue to attach the balsa to the foam core. The sample stuck solidly to the foam. Not a conclusive test yet, but encouraging. I plan to try sheeting my next core using it as an adhesive. Has anyone else tried this?
Chris

Will this stuff become the model airplane magic potion???

Yes it will.....if you can get the lid off!

Is it fuel proof?

I tested a sample after I painted my new flight box with it. Overnight with 15% nitro fuel left a sticky mess. Cure time on the sample was about 24 hours, so I don't know if it's fuel resistance would improve with further curing. Not wanting to risk the new flight box, I sprayed it with rattle can polyurethane clear which did test OK.

I plan to use the Polycrylic on my next airplane, but will treat it like nitrate dope - cover completely with a fuel resistant finish.
Steve

Talk to Doug or Godzilla. You are right, they use it for the base only, then use auto colors and clear.

>I plan to use the Polycrylic on my next airplane, but will
>treat it like nitrate dope - cover completely with a fuel
>resistant finish.

NOT FUEL PROOF!

I do not even use it to paint handles or props. Ask me why...

>Is it fuel proof?
If you use some Nelson poly paint cross linker in your minwax poly it will be fuel proof.

Been there done that. Apparently polyurethane develops a stong bond when pressure fitted. I now wipe my can lids and the lip of the can off to not seal the can. Second suggestion - turn the can over on it's top and if the can is sealed, will not develop a skin on the surface - if anything it develops on the bottom of the can.

>Been there done that. Apparently polyurethane develops a
>stong bond when pressure fitted. I now wipe my can lids and
>the lip of the can off to not seal the can. Second
>suggestion - turn the can over on it's top and if the can is
>sealed, will not develop a skin on the surface - if anything
>it develops on the bottom of the can.

Another trick is to get some sheet metal screws and drill some holes in the side of the can 180 degrees from each other just under the lip at the top. Run the sheet metal screws in. I used 3 x 5 index card stock for gasket material. When you want some polyurethane, just unscrew both screws and pour (the top hole allows air back in the can, but just enough to displace the poly poured out).

Works well, and usually doesn't result in a skim on the top. Any, you don't have to fool cleaning the can lip off again....

Ooo!!! I like this. Can't help but chuckle at the ingenuity of it.

will that work for dope as well?

>will that work for dope as well?

Sorry I missed this earlier. Yes, it works well with just about everything.

I would like to claim credit for the idea, but my old friend George MacArthur was the one who showed me the trick. George used to paint his planes with Dupont Dulux car enamel. The Dulux was relatively fuel proof and he could make a can of clear last right to the end.

>>Been there done that. Apparently polyurethane develops a
>>stong bond when pressure fitted. I now wipe my can lids and
>>the lip of the can off to not seal the can. Second
>>suggestion - turn the can over on it's top and if the can is
>>sealed, will not develop a skin on the surface - if anything
>>it develops on the bottom of the can.
>
>Another trick is to get some sheet metal screws and drill
>some holes in the side of the can 180 degrees from each
>other just under the lip at the top. Run the sheet metal
>screws in. I used 3 x 5 index card stock for gasket
>material. When you want some polyurethane, just unscrew
>both screws and pour (the top hole allows air back in the
>can, but just enough to displace the poly poured out).
>
>
>Works well, and usually doesn't result in a skim on the top.
> Any, you don't have to fool cleaning the can lip off
>again....
>
>Bob

That is one kickin suggestion!

I bought a can last weekend and am using it to attach 1/2 ounce fiberglass to bare balsa. So far it is working very nicely. As for fuel proofness, I poured some of my Carrier fuel on a sample and let it set about 1 hour with no problems. My Carrier fuel is 70% Nitro, 10% Propylene Oxide and 20% Oil. It eats dope in seconds. I may have to look at this stuff a bit closer.
Bill