[s1070.photobucket.com] have a test coming up, I'm in university maintenance, on the test I have to sweat 1/2 copper pipe and make a 45 degree 4" offset. I'm coming up with 4 1/4 on my pipe length then my fittings. I know there is a formula and I've watched videos but I'm more confused now. This is one of those things on the test they use to weed out people they don't want in the program. any help, is my measurement correct? any help would be wonderful. This will never be used in my line of work.



Edited 1 times.

I take it you want a 4 in offset using two 45s. In this case you have a right angled triangle with two sides at 4". Pythagoras's theorem gives the hypotenuse of the triangle as sq root of 4^2 + 4^2 = sq root of 16 + 16 = sq root of 32 = 5.65". The length of pipe will be at bit less since we are measuring centre line to centre line, so 5 1/4 in is about the right length, not 4 1/2 in.

multiply the amount of the offset by 1.41.. that comes to 5.99.. subtract whatever the fittings take out and you will have the correct length nipple. two 45's should take out approx the diameter of the pipe. 5/8 inch
so the nipple should be 5 3/8 inches.

packy, you need to brush up on your arithmetic. 4 x 1.41 = 5.64. I had 5.65, the more accurate figure ( though that much accuracy is not needed in this instance) since the 1.41 is the square root of 2 which is actually 1.4142, slightly more than 1.41.

First thing you have to do is measure Center Line to Center line

PlumbCat TM 2003


Plumbermandan

A 12" offset needs 17" between centers of the fittings, so a 4" offset is 1/3 of 17" or 5 2/3". Much easier to compute when you don't have a calculator, (or pencil and papper), handy.

sister mary casilda of the tabernacle door left hanging (my 6th grade arithmetic teacher) would have me sweep the schoolyard with a toothbrush if she found out about this.. shhhhh...

AFTER she beat you with her yardstick.
? get it; yardstick ?

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638