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.

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