A bit of a gap since my last post. Some activity interspersed with a lot of other activities, and that is all I have to say about that.

Finally, an Assembly! (but, not a final assembly)

I went ahead and got the tone panel assembled. The images below show the progression. There really isn’t much to say except that the assembly was without incident. Test results are still TBD, there just hasn’t been time to rig up an RC-96 test setup and perform a test of the CCA.

Coffee Time with the Chassis

While the front panel (mechanical) aspects of the chassis have been mostly completed, the back-panel was still a blank canvass. I was able to correct that over several evenings and other brief spots of time. Speaking of the front panel, here is a test print of the front-panel logo courtesy of Cortney:

It is a 2-color 3D print, with raised features. Vuury noice!!!

I used a piece of large-aspect angle-aluminum to fabricate a template for the back-panel (shown attached to the chassis). The PCB mounting holes were also accomplished in this time frame, which facilitated the alignment of the template.

This effort also entailed removing the borrowed RC-96 from its chassis so that I could get the “z” alignment of the various back-panel holes worked out (the borrowed RC-96 is what is featured in these photos). My go-to standoff height for CCAs is 0.5″ which is greater than that used for the RC-96 chassis. Also, the sheet metal thicknesses are different, so it isn’t a simple transfer of measurements kind of deal. This means I had to accommodate the differences and thus could not just copy the RC-96 chassis dimensions. This was a bit of a hair-pull because I didn’t have a reasonable way to verify the result without just cutting the holes and then test-fitting.

I used my mill to carve the rectangular openings. I could have used a Dremel with a cut-off wheel, which I have done in the past with good results, but the mill has its advantages. I got behind the 8-ball however, and ended up sending half of my 1/8″ end mill to meet its maker (the other half stepped in to save the day). I was more careful with the remaining cuts. I know better but just got careless.

The end result looks to be reasonably close. The calipers might tell a different tale, but visually, the locations appear acceptable.

Keep a lid on it, Mack!

The standard Bud box has only 4 holes to secure the “base” (which I generally always use as a lid). For both mechanical and EMI considerations, I prefer more locations than that. I placed one hole centered between of each of the long edges and two holes on the short edges which brought the total to 10. I cut a piece of steel strip to assist with pressing the PEM nuts into place. Ideally, one would do this when the sheet metal is still “flat” when it is easier to position the workpiece under an arbor press. However, using a pre-assembled box takes that off the table. Using the steel strips (one on top, one on bottom) and a pair of vice-grips makes for a reasonable work-around. The problem is, the operator must exercise great care to get the nuts pressed properly, so this method isn’t suited to mass-production.

The back-panel nomenclature will be filled in by Cortney. While I have a decent library of dry transfer characters, HE has a Cricut. Now isn’t THAT special!

At last, the bulk of the mechanical work is completed. Next, I can start to focus on a test setup so that I can exercise the RC-96 and tone panel.