Wireless Set No. 52 Canadian - Project

[David Dunlop]

Another small roadblock in restoring the Coil, Aerial Tuning No. 2 A was related to the zinc plating work all the brass hardware was going to need.
The two brass Mounting Plate assemblies are going to be the largest items I have ever had to plate and the small plastic containers I have been using for the acid etch and water rinse removal were nowhere large enough to do the job.

I could find nothing available on hand around the house the right size and on finally mentioning it to Debbie a few days ago, she suggested I check out the local Dollarama Store to see what they might have. Went in the other day and worked my way through the isles and ‘Bingo’! On a shelf marked as Drawer Organizers, I found stacks of 8.5” x 2.5” x 1.5” plastic trays that were perfect for the task and only $1.25 each, so I picked up two one for the acid and the second for the alcohol needed to remove all the water when the acid is rinsed off.

I also picked up an extra bottle of Muriatic Acid, and Isopropyl Alcohol, just in case they are needed.



David

[David Dunlop]

It is always a nice feeling when things start going back on during a restoration.

That started with the restoration of the Coil, Aerial Tuning No. 2 A with the 52-Set Project when the green wool felt pad that protects the coil chassis was the first part to be glued, and reattached to the floor of the case.

I had to take another look at the back of the pad first to be certain it was a running bead of glue which had been squirted over the back to originally mount it, and then follow suit with the new glue. It was relatively easy process. One only needs to get the two rear holes for the mounting hardware that comes up through the floor of the case to secure the coil chassis centred and lay the pad down. It will move fairly easy for a couple of minutes allowing for fine tuning of the placement and then I used an old, smooth, steel sanding block I had to firmly press the entire pad down in its final placement. This is the same glue I had used a few months back to install the reproduction Parts Lists I had to make for the Spares Cases, at it dries a yellowish colour very similar to the wartime mucilage glue used by Canadian Marconi Company. Should be all dried and set by Sunday.



David

[James D Teel II]

Is the glue dry?

[David Dunlop]

Indeed it is James.

As you can see in the first photo I had posted, several pieces of the original factory paint came up with the felt when I removed it. I left it as is primarily because the locations of these patches, along with the silvery, slug like trails of where the original glue was applied, gave me a very good idea of where the original run of glue bead had been located. The size of the bead was a bit of a guess but I must have come pretty close to what was originally applied because only a small bit of glue oozed out in three small locations.

It was all dried and cured in about 10 minutes. I had initially thought of brushing the glue on but Debbie advised against that. her logic was that a bead would be thick enough to allow me to carefully adjust the felt pad into its correct, fine position for a few minutes and let me press it down firmly once in place with an old steam iron. She was correct. I got almost three minutes of play time with the felt pad, whereas a brushed on approach would have meant near instant, permanent sticking of the felt in whatever position it touched the floor of the case.


David

[David Dunlop]

A good day yesterday and this morning.

I was able to use the new brass wire wheels to final polish the Left Coil Case Mounting Plate and hardware, acid etch and rinse it all and get into the electroplating solution for a new coat of zinc. My 2-Amp 12 volt trickle charger was getting quite. workout with such a large piece, so after an hour, I switched up to my 10-Amp charger for another two hours last evening, rinsed the plate assembly off and let it dry overnight. Blew through one brass wire wheel getting it done but expected that, given the size of these plates. Great to be able to just pick up another wheel, swap it in and keep right on working.

This morning I was able to reinstall it on the case and now I am ready to repeat the process with the mounting plate assembly for the right side of the case.



David

[David Dunlop]

It took a little longer than I expected to get the Right Side Mounting Plate assembly zinc plated. I finally realized the zinc anode plate was very reduced in size from all the work it had been doing, and could not deliver the amount of zinc to the mounting plate at the cathode needed for a fast job. I ended up fitting three worn plate to the anode and modified the cathode assembly so the mounting plate was perpendicular in the container, parallel to the anode plate and as far away as possible from the anode.

Dry now and setting up for tomorrow.

The right side mounting plate is the one with the brass ground strap connecting the front screw assembly to the lower right front panel bracket, to properly ground the aluminum front panel plate of the coil assembly, so I am going to clean and plate the lower front left and right side front panel brackets tomorrow morning to get the grounding strap properly reinstalled and out of the way.



David

[David Dunlop]

First thing this morning, I started cleaning the lower left and right front panel mounting brackets and hardware and get them into the zinc plating bath. Once that was out of the way, I installed the Right Side Mounting Plate to the bottom of the coil case.

In the second photo here, you can clearly see the longer front 8-32 machine screw used at the front of the plate in order to fit the grounding strap. There is a depression in the countersunk ho;e here which gets filled by a flat washer that gets dropped down over the machine screw before the grounding strap is fitted. If that space is not levelled off, the brass grounding strap will get pulled down into the depression when its hardware is run home. Under the stress, the brass strap eventually fails and snaps. The one on this coil. did because no washer had been fitted, but the grounding strap on my parts coil was in perfect shape and had the missing washer.


David