Filling the grain in a balsa fuselage

[Bill Burton]

Let's suppose you have sanded your profile fuselage smooth and now you want to paint it.  Water based fillers like Polycrylic can warp your fuselage.  What product would you choose to use to fill the wood grain other than dope before you paint it?

Thank you

[Tim Wescott]

If I didn't use dope-based sanding sealer I'd use Polycrylic, applied sparingly for the first few coats.

Because I haven't warped a fuselage with it yet.

It works a lot better at filling the grain if you put a layer of silkspan on the fuse, whether you're painting with dope or Polycrylic.

[RC Storick]

I would use Z poxy. Spread it on and wipe it all off and let dry. Sealed

[Randy Powell]

Back in the day we used to use epoxy or polyester resin and 1/2oz fiberglass on the fuse. Sand and paint with epoxy paint. Worked a treat.

[Bill Burton]

Thank you all

[Bill Burton]

I would use Z poxy. Spread it on and wipe it all off and let dry. Sealed

Robert, do you use a heat gun to melt the Zpoxy into  the wood before you wipe it off or is that necessary?

Thank you

[Dan McEntee]

  Search out posts by Allen Brickhaus here on this forum and SSW for his favorite finishing method, or check out some of his construction articles for a step by step description. Basically, he coats the wood with a layer of vinyl spackling compound thinned to a brushing consistency. When dry, block sand that off until smooth and even. The get some of the Z-Poxy Sparky mentioned or any finish cure epoxy, thin it a bit with alcohol and brush it on. Thinning the epoxy really extends the drying time. When dry, block sand off again and touch up areas where needed. Thinning the epoxy cuts the weight a bit and it soaks in a bit better, but not too much because of the spackling compound. Like any finishing method it takes some practice to master it, but Allen got some pretty nice and durable finishes with his method. Great for sport planes or any model really. How any finish looks at the end is a direct result of how much work you put into it.
  Type at you later,
  Dan McEntee

[Motorman]

A standard finishing method for dope. The first 2 coats should be clear nitrate no talc thinned 50/50 to get good adhesion. Then just mix some filler like talc powder or something lighter with nitrate dope and brush on a few coats. You have to keep mixing as it settles. Then sand it back almost to bare wood, repeat until the grain is filled then finish it with butyrate dope.

Bill, if you want to use polycrylic all you need to do is brush on 2 coats of nitrate dope thinned 50/50 and the water based stuff will be no problem. You'll need about 3-4 coats of polycrylic and it has to be sanded aggressively because it's thick and hard. Not my first choice for filler.

MM

[RC Storick]

Robert, do you use a heat gun to melt the Zpoxy into  the wood before you wipe it off or is that necessary?

Thank you

No just brush it on and card it all off. Finish drying with paper towel ,let dry sand and paint. I use to finish like this in the 1990s works good just a littler heavier than dope.

[Mark Scarborough]

Worked a treat.

Howard?? is that you?? are you hiding in Randys shop? I thought you were in Houston,,, 

[Howard Rush]

I would use Z poxy. Spread it on and wipe it all off and let dry. Sealed

Easy for you to say.  I lost my Z Poxy.  It's in my shop somewhere, I think. 

[Bill Burton]

Thank you all very much for the help.

BB