1.4142 will give you the travel piece C-C then you deduct for the fitting
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Measure to the center of the Ell and decuct for the threads ..
If your elbow is a short radius it is 1 times your nominal pipe diameter. If it is a long radius it is 1 1/2 times your nominal pipe diameter.show me the exact pattern of long radius
Radius=C=1.5*NPS nps=nominal pipe size
Elbow is a fitting used to change pipe direction, 45 degrees in this case, LR is referred as "long Radius" ( normally most pipes, unless you ask for SR, short radius). Butt weld refers to welding 2 ends from two separate fittings or pipe. Both ends are beveled (30 degrees is tapered from inside pipe diameter to outside pipe diameter on pipe/fitting connections)
Pipe size times 0.707
The take off formula of a 45 degree elbow pipe, will depend on what the pipe is on. Sometimes a 45 degree pipe will need a 90 degree right angle turn to come off.
15.875 x pipe size=
5/8 x pipe size
this app help you: "Miter Flat Pattern Design" in play.google.com
elbow senter making
Loosen the clamps and use some elbow grease to twist the fitting into the desired position.
.625'' x pipe diameter
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