Silly question re stock sizes

[JimM]

Hi all

Showing my newbie-ness here but when buying tube stock does the size given eg 1/2" generally refer to the inside or outside diameter ?

Cheers

Jim

 

[Jadecy]

Tubing size is typically outside diameter unless otherwise specified. On full size stock tubing is generally specified in outside diameter and pipe is specified in inside diameter.

Sources like speedy metals also show additional data like OD for outside diameter, ID for inside diameter, and wall thickness. It is a bit redundant but easier to determine exactly what you want.

 

[rake60]

In the USA tubing and pipe sizes are based on the ID size.
The "schedule" size determines the OD size.
1/2" Schedule 40 tubing verses 1/2" Schedule 80 tubing will
both have an ID of 1/2".
The OD will be twice the later for the schedule size making
the wall thickness much heavier.

Rick

 

[1Kenny]

Here is a link that is full of information about round bar, tubing and sheet. If you click on Steel Information it explains the what the different numbers mean for the steel. The 4130 Tubing section has a good chart of OD and wall thickness. The 4130 Sheet section chart has the thickness measurements so you can tell what gage you have.

http://www.aircraftspruce.com/menus/me/steel.html

Kenny