Re: Tinsmith's in frame gas tank for cantilever Schwinn.
This past Saturday Dan and I got some more work on the tin prototype gas tank.
Dan had cut a couple pieces of wood on a band saw to the same shape as the sides of the gas tank. This is not so much to act as a buck for tapping out the final flange bend, although it is useful for that, too. It's primary function is to give a backing to the tin for the soldering to come later. Unlike copper, tin has more tension and resistance to bending... spring in other words. Final shaping of the form was done with a belt sander.
If you don't have access to either of these tools, the form can be cut out with a jig saw and final shaping done with a sanding block by hand.
We already had a top piece cut from our last session, but in thinking about this little tank over the past couple of weeks, he thought it would be better if the top piece could be continuous, covering the top, front end and part of the bottom all in one piece.
The next photos show him marking and then making the bends of a machine I forget the name of (a brake?) which is designed to bend a flat piece to your choice of angle. Lacking this tool you could use a sharp edged table or workbench with a piece of steel or wood clamped above so the piece you want to bend is sandwiched between. This needs to be a clean bend. As he went, Dan checked the accuracy of the bend with the side piece to give it a bit more angle if needed.
Someday when I grow up I will probably lose interest in toys with wheels, but until then...