Squadron/Signal Putty is available in White, Green, or Gray. It is not quite as good as Tamiya, but is easier to find. Most LHS have Squadron putty but not so with the Tamiya.

The Bondo Spot Filler Putty is the easiest to sand, but the "rusty primer" red color really sucks.

I like filleting with 15min (NOT 5 min) epoxy mixed 50/50 by volume with micro-balloons. Light, easy to sand, and very strong.

Use Acetone or MEK to wipe Tamiya, Squadron, or Bondo putty.

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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, and HAVOC !