I used some that I picked up at a hot rod swap meet back around 2002. I shaped a license plate/turn signal bracket for my old Ducati M900 to clean up the tail where a PO had done the usual frame chop. The bracket was street sign stock (salvaged legally from the trash where I worked at the time) and I used the rod to seal up and smooth the open seams after bending into shape. Worked very well and was still crack free when I sold the bike some 6 or 7 years later.
Propane worked fine for the 1/8" sign stock. When I watched the live demonstration and in the instructions it says no OA - too hot and the parent metal aluminum will immediately react with the filler if it reaches the melt point. Which aluminum does without much warning, even when wearing high zoot cobalt goggles to see the puddle better through the OA flame.
If the filler is puddling and balling up, the parent metal is not clean enough. Clean it bright first with sand paper or a clean stainless brush that hasn't been used on anything else and acetone for complete degreasing. Clean it right before working it to avoid oxides forming (which starts as soon as you're finished cleaning). While heating and trying to get the filler rod to melt and stick, you can use a clean, new stainless brush to scrub the area as you are heating it to keep it frmo oxidizing. That was the trick the vendor was using during his demos. Worked for me too.
After I filled the seams and sanded the outsides to a smooth radius the seams were invisible.
Merritt Island, FL
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