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Klasskote Epoxy Substrate

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Ron King:
I am planning to go back to epoxy for my next project. I am so tired of the fuel streaks with some butyrate dope and the wife is getting tired of the smell. I used Hobbypoxy and Superpoxy on my RC pattern ships and have heard nice things about Klasskote.

I just saw the DVD's from Dave Platt and he is still using the old standard polyester resin/fiberglass method to cover and seal the balsa. I used this method on all my RC ships and think it's great. It is definietly bullet proof and fuel proof, BUT I think it might be too heavy for control line stunters.

I know Brett used Klasskote on his new bird and saw the write up on SSW. Has anyone else tried it?
How did you prepare the balsa substrate? Did you sheet the balsa wings, use foam wings, or silkspan the open bays? Butyrate, Nitrate, or ?????  ???

Thanks,

Ron

EDIT to remove brand name. Do not want this to be interpreted the wrong way.

Randy Powell:
I know Brett's plane is a foamy. All flying surfaces as far as I know. Not sure what the substrate is.

Ron King:
Randy,

Surprisingly enough, your short message answered a lot of questions.  :D

IIRC, Brett uses 00 silkspan and nitrate dope to develop his substrate. I was uncertain if he was covering open bays with this and using a shrinking nitrate from Randolph or if he had fully sheeted surfaces.

Thanks,

Ron

Brett Buck:
Sorry, I missed this one earlier.

   What I did was this:

    From bare wood, I filled the dings with Elmers Fill n'Finish and sanded it all off flat. I applied 3-4 heavy coats of nitrate, sanding lightly after 2,3,4 with 220. Then I put on 00 silkspan with thinner, wet. Then more nitrate, heavy coats of 50-50 nitrate, sanding with 220. I stopped when the surface was about 50% "plastic smooth". After I got some "starved horse" look on the fuselage, I applied one coat of nitrate with a large amount of Dave Brown plasticizer on the fuse only, with excellent effects - starved horse gone in about 10 minutes and only came back a very tiny bit later.

   After that dried well, I applied a very heavy coat of K&B Superpoxy primer. Total weight of this coat of primer, all by itself, was about 7 oz. After it cured, I sanded and sanded for about 3 days with 220 and 320. I stopped when the surface was about 1/3 white. At this point it was very shiny with a few deeper grains showing here and there. I spot-primed the bad spots and sanded again until there was no remaining grain, then polished it all up with 400. All the sanding took the weight gain down to about 2.5 oz, and the surface was excellent, and the color variation was pretty minimal.

     On top of this, I sprayed Klass-Kote white. I mixed up a mega-ton of it, and after a few experiments ended up about  1:1:.9 paint/catalyst/thinner. When all told I ended up with slightly over 2 oz of paint on the airplane.  This covered pretty well, and the color was much more uniform than I had previously done with a similar amount of K&B. Had I known it was only 2 oz I would have put on more volume, too. The surface finish was rather orange-peely and I could have used more thinner to good effect. I sanded this a little with 600 wet to knock off the tops of the orange peel.

   Then I put on Klasskote Red. I used more thinner this time, and that worked pretty well, but the gun was set up a little off and I got a lot of overspray, which resulted in me running out of paint before I was done. I mixed some more and really laid it on there. Red is pretty transparent (although Klasskote had A LOT more pigment than K&B or HobbyPoxy) so I just poured in on there to make sure it didn't come out uneven later when I looked at it in the sun. This added about 3/4 oz.

   When I went put on the blue, I found the Klasskote "Indigo Blue" was sort of a candy color, and I didn't like the looks of it. So I looked for some HobbyPoxy blue like I had used before, but I was almost out and didn't have enough to comfortably get through the entire job. So I got some K&B (which was way too bright) and mixed in a fair bit of black until it was dark enough for me. I put that on with the airbrush, no problems. The lettering was Klasskote again, black of course, using stencils I got from Jim Snelson of CLC (excellent quality, excellent service, and the price is definitely right). Worked perfectly, no issues. I couldn't measure the weight of these two, it was just small, in the noise.

    I sanded everything down as flat as I could manage with 600 wet. Epoxy is nice because you can really bear down on it with little fear of going through. At this point it looked pretty good.

    I used Phil Granderson's methods for the clear. Clean it all up with Windex straight out of the bottle. Used Magic eraser to clean up a few spots of sanding sludge, pencil marks, and overspray. Sprayed the Global System clear, thinned to alchohol consistency, with Phil's Iwata touch-up gun.  My technique was not very good (first time I had done it) and I got decent coverage but a lot of overspray. I needed to move faster. Jim and Phil were "advising" and they warned me, but that didn't help all that much. Phil said "ok, we're done, let's go eat dinner" but I noticed that the total volume sprayed was only about 2 fluid oz, and there was a bunch left. So I went back over it and really poured it on, more coverage but more overspray. I knew at this point I almost couldn't put on too much weight, so I wanted to put as much on as practical so I could rub out with reckless abandon. Net weight of clear was uncertain, but definitely less than 1 oz.

    For you finish weigh fans, thats 2.5+2.1+.66+1 oz = 6.26 oz, with complete coverage and a ton of clear to rub on. Took about 15-16 days, working in the evening, and a lot of which was spent trying to mask the airplane and  carry it to various garages around the bay area to spray. I rubbed it out with 1500 sandpaper, 3M fine-cut rubbing compound, then Meguiar's Swirl Mark Remover, then 3M Hand Glaze, then Zymol wax.

       By the time the NATs rolled around, about two weeks had passed since the clear was sprayed, and the finish was completely immune to 15% fuel.

      I was pretty happy with this system. Having done it before, it should be pretty easy to do a better job next time, with less screwing around. I might have been tempted to put another coat of clear on after some wet-sanding, and that would make the thing like a mirror. I may still do that. if the wood ever dries out enough from the rain intrustion to level itself out.

      Brett

Ron King:
Brett,

Thanks for the reply and congrats again on your well deserved win in Muncie.

The DVDs from Dave Platt are very good. A few things he does are like "old times" for me. He still uses polyester resin and 1/2 ounce fiberglass to cover his surface. I would love to do this on a stunt ship, but it would probably be too heavy. It does come out smooth and fuel proof. I miss K&B Superpoxy Primer. It was the best surface prep ever made. I will try the Klasskote Primer and see if it measures up. (Fingers crossed.)

Dave recommends a 1:1:1 mix (equal parts resin, catalyst, and thinner).  He also recommends Satin catalyst because it sands easier. His scale projects are usually flat finiah anyway, but he says you can use the gloss catalyst and get a decent clear coat.

My new ship is under construction. All the major pieces are framed up and I figure I may have it assembled by Labor Day.  All the surfaces are sheeted, so I will continue with my usual Nitrate/ 00 silkspan cover method as well, then try the Klasskote.

Thanks again,

Ron
 

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