Wireless Set No. 52 Canadian - Project

[David Dunlop]

The COVERS for the Sender, with its final exterior coat of paint.

Now to start working on the last major repair challenge before reassembly of the front panel to the Sender can begin.

David

[David Dunlop]

While waiting for paint to dry, and taking advantage of the last really nice warm weather here last weekend, I spent some time in the back garden reading up on vintage varnishes. I was frankly amazed at the amount of information that is available, and it is constantly being added to by research teams around the world involved in art, musical instrument and furniture restoration and preservation work.

In simplistic terms, a varnish consists of a solvent medium and resins dissolved therein, with or without the addition of lesser organic ingredients that influence the drying time, finish gloss or hardness/flexibility of the finished product. All vintage varnishes will colour, or darken, naturally over time and some compounds can be added to the mix to produce particular shades of yellow or orange with the initial application. Artists like Monet and Van Gogh, were aware of the natural darkening of varnishes and typically painted in lighter tones of paint to allow for the varnish darkening in the finished painting.

The three common solvents were linseed oil, tang oil and walnut oil, and if a faster drying time was needed, turpentine was used. The vast majority of resins came from conifer trees, pines and firs.

Where it got interesting was the locations for the most popular resin supplies - Malaysia, Indonesia and several of the smaller Greek Islands. It was also noted that the Canada Balsam Fir could also provide a good resin for varnish, but it had a tendency to darken rather quickly.

So it looks like, if the timeline for the fall of the above noted sources of resins during the early part of the war was compared to wartime wireless production, one would expect more late war wireless equipment to have varnishes made from the readily available Canada Balsam Fir, and these would yellow up, or darken, much more noticeably than the earlier war production items.

David

[David Dunlop]

This is the first step that I have thought my way through in regards to being able to reset the four digit indicator for the 7 – 16 MC PA TUNING, COUNTERS.

I need to know the centre point of the indicator dial when it is mounted to the front panel of the Sender, without the front panel being installed, as it is impossible to work on these COUNTERS with the front panel in place. So I need to create a temporary set of x-axis and y-axis reference points.

I did this by first setting up small strips of masking tape on the top and sides of the chassis, where the requited axes would be located. I then reattached the front panel to the chassis with the two upper corner screws and marked the relevant axes marks with an adjustable square, on the side tapes. When the front panel was removed once more, the location marks on the sides were transferred to the tape strips on the front of the chassis.

In the second photo, you can see the two COUNTERS temporarily blocked in their correct positions. Note that although the 1.75 – 8 MC PA TUNING indicator (on the left in this orientation) reads a correct ‘0000’, the 8 – 16 MC PA TUNING indicator on the right has the lowest digit stuck at ‘3/4’. In this position, the Tuning Coil and its related flexible coupling attached to the COUNTERS, are all correctly oriented, as is the COUNTERS itself. What I have to sort out is the best means of keeping the COUNTERS in that position while disconnecting the two sections of the gear drive on it from each other. If I can do that, then I can reset the indicator dial to ‘0000’ and carefully reconnect the two sections of gears, thereby locking the dial back into its correct reading when in its correct final position for reattaching to the front panel.

More on this as I sort it out.

David

[Mike K]

I guess you have seen this guys work

http://www.radiomuseum.co.uk/ws52.html

[David Dunlop]

Hello Mike.

Thanks for posting that link. Although I was aware of his restoration work via another website, I was unaware he had done any 52-Set work.

There is some excellent information work there, as I am just at the calibration and alignment point with both of my receivers, and as he noted, accessible chassis space dictated a few innovative (read remoter than usual) locations for component boards, with significant cable runs and conduits to tie everything together. I had made a note to myself to start mapping out the component locations ahead of time but noticed that work has been well done already now. That will be a huge time saver!

Thanks again and stay safe, Mike.

David

[David Dunlop]

While mulling over the challenges of the COUNTERS reset, I decided to pull the Sender BLOWERS out of storage and have a closer look at the assembly.

A good layer of greasy soot over the front of it all, but the backside was rather clean. Same for the fan blades. VERY filthy on the front side with a few rusty patched showing dull red through the crud, but an interesting amount of shiny metal showing through on the back side of the blades.

Curiosity got the better of me and I decided to clean it all up to better see what was going on.

These three photos are before the cleanup.

David

[David Dunlop]

A couple of hours later, after several solvent rinses, and a light buffing of the rusty sections, this is what came out from under the crud.

I am a bit surprised to find the fan blade has such a bright finish, but now recall seeing a photo of a 52-Set in service somewhere and the fan blades were very visible on both blowers, through the mesh screen COVERS. I must try and find that photo again, and it will be interesting to see what is going on with the Supply Unit BLOWERS when I get around to that part of the project.

David