JIC fittings

AllDodge said:

Thanks so my 29 and 47 are pretty close
But with the sheet, I'm seeing 1.73 from end of hose to end inside fitting.
So wouldn't this be 1.73 + 1.73 + 23 = 26.46?

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Yup. My mistake. Your math is right.

Thanks much

With an 8S-4055 reusable fitting on each end the length of hose required to fabricate the 068-7366 is called out as 60 cm (23.62 inch).
For the 5G-1791 also calls out 2 x 8S-4055 and the hose length is called out as 107 cm (42.13 inch).
That ought to be within the ball park but is not guarnateed to be 100% correct.

With crimped non-reusable fittings the cut length of hose required to give the correct overall length might change by a little.

Thanks much, I ordered lines based on overall lengths (27 and 46) so it should fit using the preliminary lengths used with my tape, and they were a bit long.

Nige said:

Sorry but that's not true. A 3/4" thread measures 3/4" across what's known as the Pitch Diameter. This is a diameter measured approximately halfway between the top (Major) and bottom (Minior) diameters of the thread. See below but note that the Minor diameter is not shown on the illustration. What you are measuring is the Major diameter and that is not the same as the thread size.

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Nige, I have to disagree with you. Most all standard screw threads are called out by the nominal major diameter. The outside diameter of a screw thread will almost always be under the nominal thread size by an amount that is roughly 1/10 of the thread pitch.

The pitch diameter is only of concern to machinists, and is usually measured using special pitch mics or with thread wires.

For example, the -8 in the illustration is 3/4-16. The thread pitch is 1/16", or .0625. 1/10 of the pitch is .006, so the measurement of the od of the threads will be about .744.

You're absolutely right. I have no idea what I was thinking when I wrote that, although a pending dental appointment this afternoon could have had something to do with it.
Humble apologies.