Playing around with something new here. I've been reading about metal forming processes, and this one has intrigued me. Finally found an excuse to try it out, even though I don't have a stump with bowls cut in it to form with or a fancy sandbag. I did, however, have a zip log bag full of brass shavings I'd been saving- just in case. Yeah, I'm that bad. Used it as a sandbag, found a scrap of aluminum, and went at it.
Blasted some old solder with the blowtorch, and dumped it in.
Only took a few seconds for it to cool. Turned out okay.
Tried it again with a softer piece of aluminum and a custom built planishing hammer for the job and got much better results.
The final product after some polishing:
Its a custom cast weight for MY pinewood derby car. Going to see if I can beat my boys- we have an "adult" pinewood derby coming up this weekend. Pics to follow, of course!