To the best of my knowledge, Centuri Fil-Cote was just bottles of Pactra Balsa Fillercoat, with their own private brand labels.
Conversely, Estes Astro Seal was just relabeled Pactra Sanding Sealer.

I still use BOTH for filling/sealing all rocket balsa parts.
Anywhere from 2-4 coats of Balsa Fillercoat depending on how tight the grain is with sanding on coats 2, 3, and 4. Follow that with 2 coats of Sanding Sealer with sanding of both coats.

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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, TURMOIL, FIASCOS, and HAVOC !