Weather proofing


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It's been a while since I've built any foam board planes and they've all been white paper not WR paper. I'd like to make one of the Mini Hellcats to fly in my front yard (acre) but don't want it to melt like my Old Fogey, or several other FT planes I ahd. I think my F-22 stuck together better because it was spray painted but eventually it succumbed to seperation after a dewey day. How much better is the WR paper planes AND are their any specific techniques. I know it's probably been covered and if you know the thread title you could reply that and I'll go reading. I just got around to looking for it tonight and I'm not finding the information I seek. Boomer porblems no doubt. The majority of my planes are SPAD aircraft. Don't really have to worry about waterproofing those unless you're float flying. Amaizing how much water gets sucked into flute.


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...How much better is the WR paper planes AND are their any specific techniques....
The water resistant foam is much better at standing up to moisture than the original foam board. The paper is impregnated with a wax like substance. It’s borderline water proof, you can make plane floats with it.

That said, I still prefer the original as glue just sticks better and it’s available locally. I always use some kind of water proofing. Most of my planes are covered in colored packing tape, which adds a bit of strength and is a very good water treatment, it’s one and done. A few sprinkles or a heavy dew are no worries for the tape. I have also had excellent results with oil based polyurethane, the stuff used in wood working. Just wipe it on, let is soak for a minute or two the wipe off any excess. Then after the poly dries, paint your plane. If you prefer to paint first, you can clear coat the plane with the rattle can stuff over the paint.

The brown paper foam board is great stuff, if I wanted something to float, I would definitely use it. For me, it just easier to go to the local Dollar Tree and buy the original, then give it one of the water treatments above. The water treatments are good enough for any time I want to fly.
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Alright, have poly in the basement so I can give that a try.

The first time I tried this I applied it with a foam brush and after a couple minutes I wiped it off with paper towel. I apparently didn’t wait long enough, or didn’t apply enough, because later on when I airbrushed it, the foam board warped.

The second time I applied poly, I applied it with a brush fairly thick, but not so thick as to leave runs or puddles. I didn’t wipe off the excess this time. This worked much better for me and I didn’t get any warping when I painted.

I’ve also recently tried the Campdry method and it seems to be working well, but apparently you can’t paint over it, though I haven’t tried.