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So I messed up trying to build this sucker in this thread. This is my second attempt to get it right. Unfortunately, I screwed up the original thread as only a moderator can trying to do some changes. So I changed the schematic from my original concept to this:

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I found out the hard way that those LEDs are not very predictable so you need the extra headroom to get them right as is I calculated 0.66A, in measured 0.5 A in the real circuit. In a case of dumb luck being careful planning this worked out because it dropped the total current down to under 3 amps most USB power cubes only go up around 3.1A max. I used super glue to glue these using some captain tape to insulate them,then I glued everything as shown on the plate for the stand I glued on a piece of 2 inch wide sheet metal that was basically laying around and glued that to the illuminator, i then 3D printed a base that would hold the plate and the illuminator in an upright position. . The copper strip is a piece I cut down from some printed circuit board stock to ¼" wide strips as a terminal block.

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The resistors are a bit larger than they needed to be, but if that's what you had, that's what you had.

This reminded me of a communications project I was working on as an R&D Tech in the early 80's. I had built an array of around 100 IR LEDs and was having trouble receiving the data that was broadcast (just bouncing it off the ceiling). I was talking to one of my colleagues and he asked me what I was working on. I explained it to him and the problem I was having with receiving. He said it was the fluorescent lights, opened his drawer, pulled out an envelope of pictures, and gave me a piece of unexposed (but developed) film to try. Worked like a charm.

 

Basically I wanted to overrate all the components. Including heatsinking the LEDs. Easier to mount too.