July 03, 2021

Moog System 55 Replica Case - Top Chassis

Right when I thought the design was complete and the CAD finalized for production, I noticed a minor detail overlooked on the original System 55 case. The case is strengthened by rabbet joints at each corner, a technique I have never attempted. In order to replicate the joint, I set my rabbeting bit to ⅜”, or exactly one-half of the thickness of the stock. This caused some minor dimensional changes for the initial cuts of the top chassis to achieve the desired 3Ux150HP.

Another interesting problem I ran into: In order to make the top chassis sit flush above the lower chassis, I had to remove ¼” off the depth of the top case. Lacking a table saw in my shop, I improvised and used my router table with a miter-gauge and templeting straight bit. It took about four passes per board to grind down the material. The results are surprisingly clean. This process took about an hour. If I were to do it again I would make use of the circular saw.

System 55 case: Top Chassis before stain
Top Chassis before stain.