Autonopedia

A

Mark a 1^1/4" x ^1/2" bar using the allowances given on part IV intro, paragraph (c).

Take a NEAR WELDING heat, keeping the punch mark exactly in the middle of the heat.

Cool out leaving ^3/4" hot on either side of the mark.

B

Next, upset the bar evenly each side of the mark until the overall length of the bar is reduced by exactly 1^1/2 times the thickness of the metal.

Two or more heats are required to produce this amount of upset and its shape and position can be controlled by suitable quenching.

C

Repeat the upsetting' around the second mark, again reducing the overall length of the bar by 1^1/2 times its thickness, so that the total reduction is now three times the thickness.

D

Bend over the anvil hick to form the inside radius. This radius should never be allowed to become too small.

E

Start to work up the bend, as shown here, keeping the punch mark on the diagonal of the corner.

F

Continue working up the bend like this, keeping a full inside radius and finishing the outside corner to a sharp square edge.

G

Here is the finished piece -

Note the large amount of metal which has been worked into the bends, the sharp outside corners and the perfectly smooth flowing radius on the inside of each bend.