http://profitablehobbies.com/faqs/fittings/fittings-its-just-not-fitting/ Power Carving and high speed engraving equipment, supplies and training. Thu, 22 Dec 2011 15:13:42 +0000 hourly 1 http://wordpress.org/?v=3.3.1 http://profitablehobbies.com/faqs/fittings/fittings-its-just-not-fitting/comment-page-1/#comment-437 admin Mon, 08 Mar 2010 17:09:17 +0000 http://profitablehobbies.com/blog/?p=472#comment-437 Thanks for the insight Mel. I figured there was some reasonable explanation. Thanks for the insight Mel. I figured there was some reasonable explanation.

]]> http://profitablehobbies.com/faqs/fittings/fittings-its-just-not-fitting/comment-page-1/#comment-412 Mel Joines Sat, 06 Mar 2010 02:32:56 +0000 http://profitablehobbies.com/blog/?p=472#comment-412 Why does 1/4" pipe thread measure almost 1/2" across? The answer is easy. Pipe size is determined bt measuring the inside of the pipe, across the diameter. So 1" pipe is 1" across the inside diameter, 1/4" pipe is 1/4" across the inside diameter. The threads are cut into the outside of the pipe wall. The different pressures that piping is designed to handle determines the wall thickness. Low pressure pipe has a thin wall, where high pressure piping has a thicker wall. To handle the higher pressures safely. And all of the piping has the same inside diameter measurement. This is why pipe threads are bigger than the measurement of the pipe. Tubing is measured across the diameter of the tube on the outside. So 1/4" tube is 1/4" across the outside diameter of the tubing. And the wall of the tubing is inside that measurement making the hole in the tubing smaller than the measurement across the diameter. Remember when measuring: Pipe is always ID inside diameter Tubing is always OD outside diameter. I hope this helps. Mel Joines was a pipe fitter in the US Navy. Why does 1/4″ pipe thread measure almost 1/2″ across?
The answer is easy. Pipe size is determined bt measuring the inside of the pipe, across the diameter. So 1″ pipe is 1″ across the inside diameter, 1/4″ pipe is 1/4″ across the inside diameter. The threads are cut into the outside of the pipe wall. The different pressures that piping is designed to handle determines the wall thickness. Low pressure pipe has a thin wall, where high pressure piping has a thicker wall. To handle the higher pressures safely. And all of the piping has the same inside diameter measurement. This is why pipe threads are bigger than the measurement of the pipe.
Tubing is measured across the diameter of the tube on the outside. So 1/4″ tube is 1/4″ across the outside diameter of the tubing. And the wall of the tubing is inside that measurement making the hole in the tubing smaller than the measurement across the diameter.
Remember when measuring:
Pipe is always ID inside diameter
Tubing is always OD outside diameter.
I hope this helps.
Mel Joines
was a pipe fitter in the US Navy.

]]>