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Building Tips and technical articles. => Paint and finishing => Topic started by: Allen Eshleman on January 26, 2013, 09:51:24 PM

Title: Sig Balsa Dust
Post by: Allen Eshleman on January 26, 2013, 09:51:24 PM
I just mixed some Sig Balsa Dust with some medium CA glue and got a very strong filler for the trailing edge of  `1/2 A PLANE.  Problem, the two halves were not quite touching.  There's a strong hard bond now.  The only problem - it's hard to sand the left over.

I remember using this with epoxy 40 some years ago to strengthen stuff.  I still have the same cardboard can of balsa dust. 

Is anyone still using that stuff?
Title: Re: Sig Balsa Dust
Post by: Clint Ormosen on January 26, 2013, 11:14:44 PM
Making any filler with CA is going to end up non-sandable. Epoxy isn't much better. Have you ever tried mixing balsa into Ambroid glue or Elmer's glue? At least you might be able to sand it a little.
There are a few good fillers out there that don't require any balsa dust in them.
Title: Re: Sig Balsa Dust
Post by: Tim Wescott on January 26, 2013, 11:32:48 PM
I would expect it to be rock hard.  If you mix microballoons with epoxy and push in way more than you think is remotely sensible, then you end up with something that sands about the same as balsa.
Title: Re: Sig Balsa Dust
Post by: ash on January 27, 2013, 06:09:15 AM
I would expect it to be rock hard.  If you mix microballoons with epoxy and push in way more than you think is remotely sensible, then you end up with something that sands about the same as balsa.

And if you thin the epoxy with 10-20% methanol, you can jam even more microballons or sawdust into the mix, making it lighter still and easier to work with.
Title: Re: Sig Balsa Dust
Post by: Bootlegger on January 27, 2013, 11:46:52 AM

  Does Sig still sell balsa dust. Would be nice to try it.
 Thanks a lot
Title: Re: Sig Balsa Dust
Post by: Allen Eshleman on January 27, 2013, 12:27:43 PM
I couldn't find it on their web site right now.
Title: Re: Sig Balsa Dust
Post by: wwwarbird on January 27, 2013, 01:22:57 PM
  Does Sig still sell balsa dust. Would be nice to try it.
 Thanks a lot

 Yes, it comes in sticks, sheets and blocks and you activate it with sandpaper. :##
Title: Re: Sig Balsa Dust
Post by: Will Hinton on January 27, 2013, 01:40:08 PM
Yes, it comes in sticks, sheets and blocks and you activate it with sandpaper. :##

Great shot!!! (And he's right, it works.)
Title: Re: Sig Balsa Dust
Post by: Tim Wescott on January 27, 2013, 02:17:44 PM
  Does Sig still sell balsa dust. Would be nice to try it.

The latest build that I'm doing generated a whole bunch of balsa dust all at once, while shaping the fuselage -- it all went into a jar for later use, and Friday, some of it came back out (and worked just fine, to tint some otherwise-white epoxy + microballoons).
Title: Re: Sig Balsa Dust
Post by: Bill Little on January 27, 2013, 03:05:33 PM
Balsa dust and Sigment (or Duco) makes a pretty good filler.  It sands very easily.  Not sure if any real strength is present.  Mix it up with the glue until it is almost all dust, just enough glue to "attach" it.  Those two glues are better than Ambroid in my opinion because you will not get the possible "staining" problem of the Ambroid.

BIG Bear
RNMM/AMM
Title: Re: Sig Balsa Dust
Post by: Bootlegger on January 27, 2013, 03:29:27 PM
Warb1rd,Tim, and Will you guy's just ain't right, you just ain't right... LOL LOL
Title: Re: Sig Balsa Dust
Post by: Tim Wescott on January 27, 2013, 03:33:19 PM
Balsa dust and Sigment (or Duco) makes a pretty good filler.

Ambroid tastes better when you peel the dried bits off your fingers with your teeth, though.
Title: Re: Sig Balsa Dust
Post by: Will Hinton on January 28, 2013, 05:25:35 PM
Warb1rd,Tim, and Will you guy's just ain't right, you just ain't right... LOL LOL

 n~
Title: Re: Sig Balsa Dust
Post by: Doug Moon on January 28, 2013, 10:38:33 PM
I have seen gaps filled with baking soda and thin CA.  It dries rock hard, and not all that sandable.  But it can be used to fix small cracks and stuff at the field when you are in a jam and need to get back in the air.
Title: Re: Sig Balsa Dust
Post by: Dave_Trible on January 29, 2013, 07:59:18 PM
I use my table router on balsa quite a bit and generate nice quantities of fine balsa dust.  I keep most of it and it does come in handy when mixed with Sigment as a filler putty.  I like to use it to fill gaps on the wing/fuse or stab/fuse joint along with anywhere cracks need fill.  I prefer it in the fillet areas because dope adheres to it better than most anything else which minimizes fillet blisters and lifting of the dope. Laying in a strip of carbon tissue over that makes the joint like steel and a solid form to hold the dope in place.

Dave