Scratch that. Just checked. The mounted fin is now warped. Mabey it's the basswood.

Going to switch to 3/32.

An easy way to cut basswood is to use a utility knife with a fresh blade. This will give you more leverage than a #11 Xacto knife. Use a heavy steel ruler as a guide and make 2 or 3 passes. I use a ruler from a disassembled combination square. It's very thick and dosen't bend. I cut all my fins this way regardless of wood type. Try to line up the direction of your cuts so that you always pull the knife from the edge of the board towards the center, or with the grain as much as possible, otherwise the resistance of the blade will sometimes snap the tips off of the fins.

An Xacto #6 handle with a #2 or #24 blade easily cuts through basswood fins with about 3 firm passes.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

Three new fins cut. For some reason the 3/32 cuts easier than the 1/16.

The 3/32" stock may be of a softer/less dense grade of balsa than your 1/16" stock was.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

Guys,

Great discussion. Looking for your tips for deeper spirals, like on the New Way square tube models.

I've not seen it mentioned yet but I've had good success on fins and spirals with Kilz spray-on primer.

Not familiar with New Wave, but Blue Tube has some pretty deep spirals. My early efforts using Elmer's Wood Filler were disappointing. So I tried an Apogee suggestion of using the epoxy clay that they sell. The results were quite good, but it is a royal, time consuming PITA.
I use a single edged razor blade to press the epoxy clay into the spiral, then dip the blade in a little rubbing alcohol before using it to smooth the epoxy. A little sanding after the epoxy cures and it's ready for primer - but doing a long, large diameter body tube can take hours - I sometimes need to take a break simply because my fingers start cramping up

I'm currently working on a Semroc SST Shuttle CC kit.
The cones in this kit are decidedly non Semroc-like in grain/sanding finish.
Both cones have taken SIX coats of Aero Gloss Balsa Fillercoat to fill the grain satisfactorily.
I sanded between coats 2 and 3, 3 and 4 and 5 and 6.
They now have 2 coats of Sanding Sealer and are finally smooth enough to topcoat.
No, the Balsa Fillercoat is not "defective" or thinned too much either. Same consistency as always.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

I've had an SST built for several years. It's sitting with a coat of filler waiting to be sanded. There is so much to sand, it will probably sit there like that for several more years. I love sanding those nooks and crannies soooo much, I want to savor it over a whole decade.

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I love sanding.

I’ve experimented with different methods over the years as probably most people. For low/no VOC approach on 3/32 or thicker balsa I’ve used talc/white glue mixture, followed by Elmer’s CWF, then a filler primer. Sand each step to 400 grit. Always do both sides at the same time of course. A final white primer coat sanded to 600 grit before painting.