Does anyone know the formula for finding the length of pipe (TRAVEL) between two 45"s. Thought I could remember it but I was wrong. :furious:
Yup, that's it. I use it almost every day. Bugs the crap out of me to see a journeyman holding a 45 up guessing a traveler.Multiply the center to center by 1.41, the subtract the fittings, I think. I used to do it every day for sump pumps, but It's been too long.
Google Books has it for yaDoes anyone know the formula for finding the length of pipe (TRAVEL) between two 45"s. Thought I could remember it but I was wrong. :furious:
I provided the formula for a rolled offset, where you are changing both the height (Advance) and the distance apart (Spread), you are doing the math for a simple offset.Um... you folks are making things complicated and Killer, I'm not sure what the heck Spread and Advance refer to.
Think of a right triangle, 45, 45, 90. The two short sides are equal. The long side is calculated by using the
Pythagorean theorem. The three sides are A, B, and C, so A squared, plus B squared is equal to the square root of C.
Now, think of a vertical pipe that needs to offset 6 inches. You use the 6 inches and multiply by 1.4142, and that will give you the center line to center line distance between the two pipes along the path of your angle, or 8.48 inches, which rounds to the nearest 1/16th of an inch, or 8-1/2". You have to compensate for the fitting make up distance, which is subtracted from that length.
BTW, your offset will always equal your rise and visa versa in a 45,45,90 triangle.
A picture is worth a thousand words so...
If you were to do as Killer says, 6x6=36, 36+36=72, the square root of 72 = 8.48528. If I then multiply that by 1.4142, I come out with something just under 12. That won't work, even after I subtract for the fitting make up. That's why I got lost.
Just multiply the offset by 1.414 and then knock off the fitting allowances or make up and it'll fit like it was made to go there.
No, a rolled offset is offsetting two ways as opposed to a simple offset where it remains on the same plane. In a rolled offset you offfsetting both side to side as well as up and down at the same time using two fittings.It's the same thing depending on how you look at it, right?