Bubinga

I know that I said I wasn’t going to do a lot of posting about my new project, but this morning’s session is worthy of a quick note.

I had the opportunity today to sit down and finish up the wiring on the source selector unit chassis. It has been a productive week for this project. Now that the chassis is in good shape, I’m free to move on to the assembly and wiring of the vacuum tube circuits.

I made some progress today on the Source Selector Unit. The twelve twisted pairs are all soldered to the selector switch and I managed some chassis wiring as well.

I’ve been waiting for some wire I needed for twisted pairs and a Fender style fuse holder. I really like these fuse holders. I find them sturdy, good looking, and reliable. I have some cheaper ones but I reserve those for brassboards, quick projects, test equipment, and the like. While I’ve been waiting for my deliveries, I’ve been populating the chassis.

I’ve finally completed the finishing of the bubinga chassis. It has four coats of hand rubbed oil finish. It really makes the wood grain stand out.

Today I got the shop cleaned up and applied the first coat of oil to the bubinga chassis for the Source Selector Unit. (Still looking for naming suggestions, by the way.) The oil really brings out the grain. I think it will look even better than I thought it would.

William Shakespeare famously wrote in the play Romeo and Juliet,

What’s in a name? That which we call a rose
By any other name would smell as sweet.

So this is my quandary today. What should I “officially” name my latest project?

I’ve been catching up on all my spring chores and managed to steal a couple of hours in the shop this morning. The Source Selector Unit chassis is now all sanded. I also took the time to cut and fit the aluminum for the top and bottom plates. Now my attention will turn to getting all the holes laid out and drilled on the aluminum.

I actually spent a fair amount of time thinking about how to dress the chassis edges for the Source Selector Unit. But after much deliberation, a couple of scrap tests, and some evolution in thought as it progressed, I believe I’ve found a solution I really like.

A good friend of mine, who’s opinion I value, has made a suggestion concerning the Source Selection Unit chassis. And I’m looking for some input.

The chassis for the Source Selector Unit / Preamp is out of the clamps. I removed the clamps, cleaned up the little bit of glue squeeze out at the joints, and gave it a light sanding. It looks fantastic.

Today, I did a little drilling and then got the chassis into glue up.

So I had another productive day working on the Source Selector Unit / Preamp chassis. The chassis has all the major woodworking complete and is ready for glue up.

About a month ago I had an exchange with a reader talking about The Purpleheart Signal Meters and modifying the project to provide multiple inputs and some gain balancing. I’ve been giving this a lot of thought in the last couple of weeks because I have the same needs. So I think this is going to be my next major project.

I have been doing internal layout work and making some design decisions concerning the new SET amplifier. I have also been looking at different materials and I decided that I wanted to make the top plate holding the transformers and tubes of brushed copper. While this is an simple decision to make at this point, it raises the issue of what wood to choose for the chassis frame.