I did this, too. I used 10U rails screwed into 'picture frames' that I made out of 1x2" furring strip. The actual thickness of "1" is 0.75", so the 1.5" added width on each side makes the frames exactly 19" wide to fit inside a standard rack. 5- 2U MOTM modules wide. My motivation was to have the width match up with my frac-rack stuff.
I built a wooden enclosure to hold two frames (one above, one below, so far ;) . After some experimentation, I angled the bottom frame so cables plugged into the upper modules would better clear space in front of the knobs underneath. I figure I can easily unscrew a frame and mount it anywhere, or put on rack-like ears at the sides to fit them into a standard rack. I can build a bigger box and put more frames in at different angles, or whatever. Illumination could be installed above each angled row for a performance situation.
I discovered the standard rack rails (Mid-Atlantic?) had slightly less than a perfect 90 degree bend in them. So, I first screwed each horizontal rail onto a wood strip, then mounted a module on each end of each pair of rails to be sure the bolts went in easy. This established the relative angle of the top and bottom pieces of wood. I then drilled and screwed for the side pieces of the frame while the end modules were in place. The modules wouldn't bolt in straight and easy if the top and bottom of the frame weren't first aligned in the Z-axis. After establishing the shape, I beefed up the corners of the frames with flat metal angles to be sure it doesn't shift.
For mounting the modules in the rails, I used standard rack bolts with nylon washers. Personally "rack rash" doesn't bother me, but since people mention it when describing the condition of their gear, I figure why not prevent it. The pliable nature of the washers also seem to help maintain secure mounting of the modules.
I took pictures of the process, and can post some of them on the group site if anyone is interested.
-Karl.
In a message dated 5/28/2008 12:37:59 P.M. Eastern Daylight Time, dave@... writes:
I used standard rack rails running horizontally when I built my cabinet.
Standard rack screws will fit through the holes, but the large heads
tend to obscure some of the panel graphics. I just looked around for
some of the same size (10-32?) with a small head. Found some allen head
ones that work nicely and are stainless steel so the little heads help
as markers for module boundaries as well. Due to the arc of the rail
bend you end up with about 1/8" gap top and bottom but I think they work
fine.