Balsa Filler From Dope and Dust

[Mike Griffin]

I read somewhere (might have been on here) that a good balsa filler is to take dope, either Butyrate or Nitrate, and mix balsa dust with it and it makes a great balsa filler.  Has anybody done this and if so does it work?

Mike

[Reptoid]

Haven't tried balsa dust but if you add some Zinc Stearate, unscented talk, or corn starch to nitrate dope it works very well and is relatively light weight.

[Hoss Cain]

I read somewhere (might have been on here) that a good balsa filler is to take dope, either Butyrate or Nitrate, and mix balsa dust with it and it makes a great balsa filler.  Has anybody done this and if so does it work?

Mike

Depending on your definitions of "....makes a great balsa filler." and "....does it work?", almost anything like that works. I have over my 60 years of active modeling, I have used all sorts of such items. Wan'na a hard filler for a hole prior to using the dope and dust, try filling with some damp baking soda, thenLIGHTLY spray some thin CA. Have your nose clear as that can sting. It makes a strong hard base for your regular filler.
Using a filler base for dope, will always tend to shrink a tad more each time you base and/or paint with dope.

[Randy Cuberly]

I read somewhere (might have been on here) that a good balsa filler is to take dope, either Butyrate or Nitrate, and mix balsa dust with it and it makes a great balsa filler.  Has anybody done this and if so does it work?

Mike

Balsa dust works fine, as does Johnson's Baby Powder with dope for small filling small imperfection like dents etc.  I wouldn't use it anywhere that requires a thin application (thin as in amount of material not viscosity).  For applications like thin sections I would use only finishing epoxy and micro ballons.

Randy Cuberly

[Randy Powell]

Just remember that if you use dope as a base, it will continue to shrink. Forever. So fillers using dope as a base, regardless of the material you use as filler (ie, balsa dust, talc, zinc sterate, whatever) it will be prone to cracking and will continue to shrink. It the problem using non-catalyzed glazing compounds. They continue to shrink and will "sink" into balsa over time.

[Bob Kruger]

I read somewhere (might have been on here) that a good balsa filler is to take dope, either Butyrate or Nitrate, and mix balsa dust with it and it makes a great balsa filler.  Has anybody done this and if so does it work?

Mike

Mike;

In gunmaking, I have used tung oil or some of the urethane blends and the sanding that occurs between layers to fill grain in walnut.  Because the shrinkage is minimal, this actually works out well.  There is little concern that the filler will actually match the color of the wood, so it works out well.

With balsa and dope, I would be suspect that this would be a long term solution.  Walnut is fairly dense, balsa isn't and will continue to compress.  If you use butyrate, it never stops shrinking, even with pasticizer.   Given the two, I think eventually eventually you will see grain reappear.  I may be wrong, as I have never used this technique to confirm or deny the occurence, so this is subjective.

Bob