Last pour I did while pouring a flywheel casting I heard a wofff …..box caught on fire ..no big deal poured the other 3 boxes …..same sand mix no fire in the other boxes The flywheel box was still burning ….top bottom out the side between the cope and drag nice blue flame loll like gas best guess to why…. …. Sand still stuck to the cast same as if it had no coal dust ….oh 4 % coal dust by weight Casting turned out good Thanks Todd
at first thought, 4% seemed high, looked it up and up to 10% is recommended in facing sand, guess im getting old and forgetful V/r HT1 P.S. the woof may have just been the box catching fire
That is what I use, so the woof you heard is gas being generated from the coal dust and ignited by the molten cast iron.
