sheet metal adaptor

[nc9933]

I need an adaptor for a gas stove , exactly 4 and 1/16 OD.Using galvanized sheet metal .o15
Using the formula, what is the length needed. I will add for crimp and rivet so dont include that. thanks.
Also is there a cheap metal stretching tool available to tweak sheet metal pipe end sizes
, not extreme stretch but just small ones.

[keebler303]

You want to know the circumference of pipe. The equation is diameter*pi=circumference. pi is equal to 3.141592....

So you need a piece 4.0625*3.141592 = 12.763" wide. This should get you pretty darn close.

There are tools like what you want for exhaust tubing, I would assume they make larger ones, dunno. There are also machines like rollers which can bead, stretch or shrink metal, I don't know anything about them but I know they exist.

Matt