Ossus Amplifiers - Step 4, cabinet assemble part 2

I've been busy the past three weeks. Work's been a bit hectic and time consuming, but despite that distraction (get it?) I've made some good progress. Better yet, I have pictures. Let's get to it.
All of this happened about two weeks ago. Before that I had taken the PDF files with the designs for the chassis, turret board, and electronics schematic to a Kinkos and paid (way too much) to have them printed at scale in color. Now is where that money starts to pay off. The following picture shows the component layout (the big sheet of paper), the garolite board with the turret drilling layout, and the chassis with its drilling layout as well. The layouts were rubber cemented to the pieces. Just secure enough to allow for easy drilling. I thought it was a better idea than masking tape, your call.

Next is a picture of the garolite board placed inside the chassis where it will ultimately live.

I thought I'd put the parts onto the chassis just to get a feel for things. I forgot to mention, my etched face and rear plates arrived mid-last week. I went to look at them, but they had a protective covering. I almost peeled it off when it dawned on me, keeping that on would protect the plates when I drill them later. I left them in thier bubble wrapped and placed them at the front of the chassis. I put down the three tubes where they will live, and the two transformers.

Notice that the transformers are aligned at a right angle to each other, this cancels their noise out of the circuit. Here is a front view to get an idea of how the parts will sit on top of the chassis.

Here is a top view where I've placed the garolite on top to see how it will ultimately align with the parts on top. The garolite will end up inside the chassis, but I was curious to see how things would be wired. So there you have it.

Here I've removed the tube boxes and put down the tube mount rings just because they are cool and I wanted to ensure that the drill holes lined up.

Then I noticed something odd. The two transformers were about the same size. I remembered from other pictures that one should be larger than the other. Hmmmm... Then I looked at the mounting holes for the Hammond 125ES, they didn't line up with the transformer. Something was amiss. I went back to the pictures of finished amps to see if the drawing was off, or if the part was wrong. The pictures showed that I had a Hammond 125ES and everyone else had a Hammond 125ESE. Turns out I bought the wrong transformer. I called Angela's and ordered the proper one, look for the other one on eBay soon. It pays to double and triple check things. You can see in this photo how the transformer does not line up properly with the holes.

On to the cabinet, I put together the amp cabinet. Before I did that I painted the pieces with a flat black spray paint. Then I glued and screwed (1 1/2" wood screws) each of the 2"x1"x1" support pieces. I glued each edge using more of your basic wood glue, then put five 2" wood screws along each edge. I filled in the screw countersunk holes with a bit of DAP plastic wood filler. I used a router to put a 1/2" round edge on all exterior sides. I had to do some adjustments on two of the support pieces, they prevented the chassis from sliding in by a very slight margin. A little sanding and that was fixed, I'll touch up the black paint and paint the exterior at the same time. This picture shows the amp cabinet assembled with the chassis in viewed from the front.

The wood working continues next with the speaker cabinet. It's laid up in this photo with angle brackets. I've pre-drilled and counter sunk five screw points at each edge. With those in place I'll take the pieces out of the clamps and place the supports for the front speaker panel and the rear baffles. I need to cut the hole for the speaker out too. The speaker will mount to the board using t-nuts. I'll use the same to mount the speaker board to the braces. Once everything is measured, drilled, glued, screwed, holes filled with putty, and painted I'll screw the sides together and route the edges to match the amp. You can see the amp cabinet sitting on top of the speaker cabinet, then off to the left is the Celestron speaker.

That speaker is huge. I have a big hand, I don't think you can appreciate its size until you see one in person. It should sound terrific.

So, good progress on a few fronts. I need to push ahead on drilling out the chassis top, face plate and chassis front, back plate and chassis rear, the turret. I'll also move some of the speaker cabinet things along to get it to the same point as the amp cabinet.
Lots of work left, nothing too tough yet. Wiring will be a challenge. One mistake there and the consequences range from a poor sounding amp to a good high voltage shock. But I have a solution for testing the amp for ground faults that I'll detail in a future post. That should give me a way to avoid shocking myself, which is a good thing.

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