I wouldn't think you needed to roll it hot. A 20 inch radius or 40
inch diameter is not that big of a bend. Also you can run the sheet
through the roller more than once.

For heat you need both fairly high temperature and a lot of BTU's. A
weed burner will give a lot of btu's and will be hot enough. But if
you can get some help and have one person with a weed burner and
another with a oxy/acet torch....... You can get the sheet hot with
the weed burner and then use the oxy/acet to get the place where it
needs to bend red hot in pretty much in a line.right by the angle.
Without using the weedburner first, it would take a lot of time with
the oxy/acet torch and cost a lot of gas.

Harbor Freight has a decent weedburner for about $15 when on sale.

Where are you located?


Dan