Wireless Set No. 52 Canadian - Project

[David Dunlop]

This particular stencil is probably the most interesting of the 52-Set stencils I am aware of to date.

As you can see in the photo of the original surviving markings, it is not a true stencil marking, but some form of silk screened product, perfectly centred on the upper left side of the Carriers No. 4. The characters are definitely all 1/2-inch in height, but slightly slimmer, and without the webbing the stencil cutting machine produces. The line lengths are a very close match but the overall height of the three lines on the stencil is 1/4-inch lower than the actual markings on the Carriers No. 4. Also, there is no means of cutting a lower case, underlined ‘o’ on a stencil machine.

When I started this project, I assumed Canadian Marconi Company built everything for the set but actively contracted out for components. I am not sure why I made this assumption considering I knew Northern Electric had built the Supply Units for the earlier No. 9 Sets made by CMC.

I have now learned RCA and Philco were clearly providing major sub assemblies and accessories to CMC for the 52-Set as sub-contractors. The sheet metal work required for the chassis of the Receivers, Supply Units, Senders and Coils Aerial Tuning (and probably the Remote Receiver Case) would certainly be within the capacity of Marconi’s shops to have produced, and with the exception on the Remote Receiver Case currently soaked with NATO Green paint, all the other chassis bear CMC inspection stamps punched into the metal.

The Carriers No. 4 is a somewhat different beast. Although the basic three compartment box is the same gauge metal as the chassis items, the Carriers No. 4 has some very heavy duty steel formed and fitted to it. It would not surprise me at all if the Carriers No. 4 were sub contracted out by Marconi for production and whatever company manufactured them used silk screen style tools for the markings. When I eventually get to the point of restoring the Carriers No. 4, perhaps some stampings will show up on the metal parts somewhere that will shed more light on this bit of 52-Set production.

In the meantime, I now have a stencil I can use for this marking, if all else fails, and enough time to explore silk screening options a little more to see if there is a way to easily replicate this item.


David

[David Dunlop]

This test meter arrived in the mail yesterday afternoon.

In the original Issue 1 of the F524 2nd to 4th Echelon Work Manual for the Wireless Set No. 52, when doing calibration/alignment work on the Sender, one had to construct a Dummy Load from a number of switches, capacitors, resistors and an ammeter to tune against. However, in the 18 January 1961 Revision 2 of F524, this Marconi Instruments Ltd TF957/1 Wattmeter was available to do the work for the Low Power output work on the Sender. It was simply connected between the Aerial and Ground, along with a 120 V, 150 W Light Bulb and away you went with your test work.

At the same time I had discovered this information, this meter popped up for sale on eBay out of Alberta. Quite a surprise when it arrived. I was expecting something in size comparable to a typical RCA, or Simpson, Multimeter of similar vintage, but this 15 lb, 12 inch high by 10 inch wide by 8.5 inch deep beastie showed up instead. Quite a size for a passive piece of test gear.

The meter is a Marconi Instruments Ltd, England product from 1957 and the TF957/1 was the export version of the TF957 for the North American Market. The main differences are the use of BNC terminals for the 1-Watt and 25-Watt test connectors and both circuits being standardized to 52 Ohms. This one was owned by the Canadian Army and probably disposed of shortly after 28 April 1994. That was the meter’s last calibration date with the next one noted as being due 15 July 1995. Missing the extension cable for the probe, one cover latch assembly and the Instruction Manual/ Card, which probably stored inside the cover with the probe and extension cable.

As much as it would have been fun to build the original Dummy Load, this is going to be so much easier.


David

[David Dunlop]

Two sets of Stencil Brushes arrived in today’s mail. They are natural bristle, square cut and small enough to work with the ½-inch stencils I recently cut for the 52-Set Project.

I toyed with the idea of tracking down an original stencil brush, the type with the paint reservoir handle, but they would be much too large for such a small sized stencil and with the oil board being close to 1/32-inch thick, I would likely have issues getting paint easily into the cut-outs without serious risk of too much paint suddenly blobbing under the oil board.

From what I have read on the current crafting media, it is far better to use very little paint and build up the density you need in several layers.

Fortunately, I have enough ‘goofed’ oil board stencils to practice on until I get the process right.


David

[James D Teel II]

Stencil brushes are cool and all, but I've found that a cut off piece of new kitchen sponge works just as well and with much less expense.

Keep up the good work. I can't wait to see it all in operation!

[Bob Carriere]

They have cheep foam on a stick for dabbing and I have used off white...looks a bit grimmy poster acrylic paint in small bottles.... very thick and works well.

.....and yes let it dry and dab again for more density. sticks very well on flat OD...... not sure about semi gloss finish.

[David Dunlop]

James and Bob.

Thanks for your feedback. Your timing was spot on in that Debbie and I had just been up to the local Michaels for some yarn for Debbie and I took the opportunity to see what they had in stock for stencil brushes. They had some dome shaped bristle brushes available and a number of the foam type you described. Debbie says the foam ones are called ‘pouncers’ in the Crafting World. Who knew.

I also had a look at the paints you mentioned, Bob. The white you described was not in stock, unfortunately. They had a sale on and it looked like that shelf had taken a hit.

I am using a latex paint for the boxes/cases and plan to pick up a small tin of the plain white eggshell finish base coat you add the tinting to, to do the stencils with, so should be OK there when the time comes.


David

[David Dunlop]

Spray painting today, in spite of perfect weather, did not go well.

I did a lot of oil based enamel spray painting years ago, but this was my first attempt at working with a latex paint with an air gun. After a lot of reading, the key issue in working with a latex paint in an air gun is the viscosity. From there, it goes tricky very quickly. There are quite a few thinning formulas out there and all come with warnings. Too thick and the gun plugs and you have to be fast to clean it. Too thin and the number of required coats to get the colour you want and the finish, goes up. At the same time, the colour starts to get lighter and if you go too thin, the tint particles start falling out of suspension. After an hour of fiddling about, I could not get the gun to draw the paint through it at all, so gave up and wasted more time cleaning up the gun and making sure it could at least spray clean water in the correct pattern before putting it away and bringing out the backup plan, small paint roller.

Two coats and four hours later, the tool box is safely back in the basement to cure and harden.

I started with a block of 4x4 under the bottom of the box and painted the back of the box first. I then carefully picked the box up by the sides and turned it to face me and then tilted it towards me letting the lid swing open until the box was upside down.

I then set the lip of the box across two pieces of 4x4, while swinging the lid forward to rest on a 2x4. In this position I could then easily paint all the other remaining sides of the box. After four hours, I repeated the process for a second coat and then brought the tool box back into the basement to cure The attached two photos show it curing in the main painting position described above.

One thing I will do differently with the other boxes/cases is to prime all the hardware by hand as I did this time, but then finish paint all the hardware by hand as well, before going to the roller. On the bright side, the roller application has produced a very nice finish to the paint and I think it is going to work out very well.


David