5/16" Tubing OD

[Matt Kivi]

What is the outside diameter of 5/16" tubing. Making my own tubing tool. Thank you!

[Arctic Fox]

A check with my calipers showed right around 0.415 in.

[Matt Kivi]

Thank you artic fox, just what i needed to know.

[Trapper2]

.401 on one piece and .408 on another.

[maple flats]

make the diameter close to the larger, but have each half of the clamp less than half a circle. Then make them adjustable. Many who make the tools, including those producing for maple companies use the long nuts sold for all thread. They then run a slightly larger drill bit in about half way, to allow for tubing expansion as the fitting slides into the tubing. The other half usually gets the sharpness on the threads removed so it doesn't nick the tubing.