server rack question

[Red Squirrel]

From my research a server rack is 19" wide. Is this measurement from the edges of both vertical rails? So does it mean a piece of equipment is 19" wide as well (not counting the L clamps on both sides)?

I'm designing a wood server rack/shelving unit and I want to ensure I engineer it well.

 

[mpilchfamily]

From outside of the bracket to the outside of the bracket is 19". The case bodies are typicly 17". If you include the rails the cases are ussually mounted on to slid in and out of the rack as needed then its about 17.5".

The mounting holes on the front of the rack are about 18 7/16" on enter. I'm getting the best measurments i can off the racks here at work but i'm stuck with only a pair of 18" wooden rulers.

The inner mounting holes, those used for the rails, are 18 1/16" apart.