By Corky Guenther

This was not supposed to be a continuing saga however here we are.  As I said before, I used up a considerable amount of plywood making prototype bracket iterations.  Bracketry got delayed while I spent time mocking up the AC hoses and routing them and the oil cooler hoses.  The right front of the engine bay is getting crowded.

It occurred to me that Dave Ahrendt does some 3D printing so I asked him if he would be able to print prototype brackets.  We spent some time working out the scaling and he printed away.   After a couple of more iterations, I was satisfied that the design would work.  Then, it occurred to me that a printed part could be used as a drill template if the holes were made small enough and the part thick enough.  After determining the smallest hole size Dave printed a complete set.  The holes were a just the right size for a #54 drill.  I figured that using the smallest size drill possible would reduce the positional error of the holes.

Since I don’t have steel fabrication capabilities, I decided to make the brackets from 3/8” aluminum rather than 1/4” steel.  The additional thickness will add sufficient strength and will not impact the mounting of either the AC compressor or the alternator.  I fabricated the aluminum using a bandsaw and a router.  First, for each bracket, a starter dimple was drilled for a hole at one end of the bracket.  Then the hole was drilled and tapped, and a flat head #4-40 machine screw used to attach the pattern.  Then after clamping the pattern to the blank, the same procedure was done at the other end of the bracket.  At this point, I drilled starter dimples for each of the other holes in the bracket.  Then the outline of the bracket was traced on the blank using a Sharpie and cut out on the bandsaw.  After reattaching the pattern to the blank and using a carbide flush trim bit in a table mounted router, the brackets were finished to size.  Then the holes were drilled to final size and tapped where required assembled and attached to the compressor.  Final installation awaits completion and installation of the oil cooler hoses.