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  #301  
Old 23-04-20, 20:09
David Dunlop David Dunlop is offline
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Default SEMS Fasteners

I have been taking a closer look at the panel mounting hardware on this Sender. A two-part reason for this.

Firstly, I want to know exactly what it is I have on this Sender, and secondly, once knowing that, I want to try and determine what is correct and what is not.

I started by numbering all 31 screws I had removed, on the foam board I transferred them to, and then I spec’d each of them out and recorded the data obtained. Apart from seven specialty screws, all others were 6 – 32 thread cutting of ¼, 5/16. 3/8 or ½ inch lengths.

I made some inquiries about possible specific names for thread cutting screws, in the process of which I stumbled across references to SEMS Fasteners. When I looked these fasteners up on line, it turns out pretty much any screw or bolt can become a SEMS Fastener. This fasteners claim to fame is the fact the shank of the screw, directly under the screw, or bolt, head is machined down slightly thinner than the following thread. A split washer is then fitted in that space and essentially held captive there.

With the exception of the previously mentioned specialty screws and two other in the panel, this type of fastener was what was being used as the panel mounting hardware. When I went into the Hardware Listing for the 52-Set, I found them listed as SEMS Fasteners. The big advantage of this hardware on an assembly line is the amount of time saved at stations where the workers do not have to fit individual screws and washers together before installing them. Both pieces are automatically together.

The other interesting thing in the Hardware Listing was that only two lengths of 6 – 32 SEMS Fasteners were used installing the front panels: 5/16 and 3/8 inch. So the ¼ and ½ inch ones I have present are clearly substitutes. That is a big help at this point.

David
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  #302  
Old 27-04-20, 23:04
David Dunlop David Dunlop is offline
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Default TERMINALS, Aerial, No. C1 ZA/CAN 4716

At some point the front panel of the Sender took a hit on this TERMINALS, snapping the small phenolic resin mounting plate for it. I had hoped it was a simple break that could be carefully glued back together, but no such luck. As you can see, a clean break on the left side but nearly 1/8-inch of material has gone missing on the right side.

Fortunately, an identical TERMINALS is mounted on a somewhat larger phenolic board on the 52-Set Receiver and I have one available on my spare receiver. I will have to identify and source the small plated brass tube rivets used to mount the board to the front panel before I can do the replacement, but at least it is doable.

David
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WS No. 52 TERMINALS, Aerial .JPG  
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  #303  
Old 27-04-20, 23:12
David Dunlop David Dunlop is offline
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Default Sender Capacitor C39A

It looks like the only electrical component that was replaced during the 1966 202 Workshop overhaul was this capacitor. The orange coloured one on the upper right side of the photo. It functions in the PA Bias Circuit as the AF Bypass and is rated at 5 mf and 300 Volts. The original was nearly 1 inch in diameter. This one would be about two thirds of that size.

Not bad really for a set that was likely in service over 20 years at the time of overhaul.

David
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WS No. 52 Sender Cap C39A.JPG  
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  #304  
Old 27-04-20, 23:36
David Dunlop David Dunlop is offline
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I was able to get the usual assortment of nylon, plastic and fine brass toothbrushes out today, along with a small electronics vacuum and an air gun set to 30 lbs., and get most of the dust and dirt cleaned from the chassis interior, followed by a careful wash and dry where needed.

Included in that process was the IPA 7 – 16 MC Flick Drive assembly from which the lower flick arm had become disconnected. The parts were in good shape and cleaned up well. The reassembly was straightforward and it is nice to see the parts back together again. I will refurbish the upper Indicator Flags on the three drives at a later date and try and get all that painting done and out of the way at once.

One thing to be aware of with this particular Flick Drive. It is not as secure in the chassis as the other two when freed from the front panel and has a tendency to wobble a bit if bumped.

David
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WS No. 52 Sender 42.JPG  
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  #305  
Old 28-04-20, 00:11
David Dunlop David Dunlop is offline
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The two bottom sidepieces of the Sender chassis form the two rails it slides in and out of the Carriers No. 4 on, and they are held in place at the front of the chassis by the two lowermost panel screws. A pair of countersunk screws secures the back ends of these two rails.

Standing water a couple of inches in from the front of the rails had created a pair of noticeable rust blisters on these rails and I found these dug into the paint on the inner base of the Carriers enough to really make it hard to manoeuvre the Sender in and out of the Carriers as the rust blisters really dug into the paint.

The paint will eventually get stripped out of the interior of the Carriers, but in the meantime, I took advantage of the access to the bottom of the rails to buff the rust away and get a smooth metal surface back where it belonged.

One thing of note with these rails, as per the photos attached. They are heavy for their size and when the front set of retaining screws are removed, the rails have a tendency to swing towards each other. The one on the left about ¼-inch and the one on the right about 1/8-inch. Since these rails hold the thread for the panel screws, they need to be pulled into alignment when the panel goes back on. A small set of spring clamps should work nicely.

David
Attached Thumbnails
WS No. 52 Sender 43.JPG   WS No. 52 Sender 44.JPG  
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  #306  
Old 28-04-20, 00:42
David Dunlop David Dunlop is offline
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Default CANS, Metal, Shields Valve No. C1 ZA/CAN 4232

Two of the four 6V6G Valves in the Sender are shielded; V5B and V5C (the Driver Doubler and Driver respectively). They are visible right inside the Access Door with the two spring clip retainers secured against the tops of the two CANS with a wing nut.

The tops of both cans had accumulated water over the years, with V5C, closest to the front of the Sender being the worst. To get better cleaning access to the interior of the chassis, I pulled everything from the wing nut down to the CANS and decided to clean them up before reinstalling them. An interesting installation.

The wing nut was straight forward enough. The next down was a bit of a surprise; a small C-Clip. Popped it off and then the Spring Clamp for he CANS on V5C came off. Next a flat washer, followed by the Spring Clamp for CANS on V5B. At the bottom of the threaded post was the final flat washer.

It took a bit of cleaning but they now look aged, rather than totally neglected.

David
Attached Thumbnails
CANS, Metal, Shields 1.JPG   CANS, Metal, Shields 2.JPG  
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  #307  
Old 28-04-20, 18:09
David Dunlop David Dunlop is offline
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Default Changes in Composite Resistor Colour Codes

I almost forgot this little bit of electronics history.

Back in Post #303 about the sole upgraded/replaced component in this Sender, I neglected to mention the odd looking yellow component tucked in below the capacitor. It looked like a resistor to me but the markings were nothing I had ever seen before.

I took a photo of it and sent it to Jacques Fortin for identification. I received his reply last evening in which he confirmed it was indeed a composite resister with a pre-WW2 Colour Code. In the Sender, it is R46B in the PA Circuit for V7A, the 813 Power Amp. The resistor provides the keying bias.

Armed with that information, I went looking for its partner in the Sender, R46A, located in the V5D (6V6G) Screen circuit, where its job is to provide voltage dropping. When I found it, it sported the more conventional coloured ring code. Both resistors are original installations, with no signs of replacement on either.

The earlier code used a full body colour on the resister to identify the first rating digit. A wide band at one end was the second digit and the ‘Multiplier’ was a third band or blob in the middle of the resister. The Gold, or Silver, tolerance rating (if applicable) was applied at the opposite end from that for the second digit.

This older resistor coding pretty much disappeared in the 1940’s, but when I checked my Amateur Radio Handbook from the mid-1960’s, a detailed explanation of this older coding system for resistors was still provided. The information was completely gone from the handbook for my Amateur Course a few years ago.

Jacques also sent me the attached photo of some of these old resistors he has on hand. Colourful little suckers,

David
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Vintage Resisror Colour Coding.JPG  
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  #308  
Old 02-05-20, 04:13
David Dunlop David Dunlop is offline
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I was able to cut two small pieces of 2x4 to block up the two Indicators today. This takes the load of their weight of the couplings to the Condensers and stops them from wobbling around.

All removable pieces are now off the Sender front panel as well, with the exception of the remains of the small phenolic resin mounting board for the TERMINALS, Aerial at the top of the panel. I need to carefully drill off the crimps holding the rivets for this board in place to remove the rivets, I need to size and source replacements to put a new assembly back in place when the time comes.

David
Attached Thumbnails
WS No. 52 Sender 45.JPG   WS No. 52 Sender 46.JPG  
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  #309  
Old 06-05-20, 18:27
David Dunlop David Dunlop is offline
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Default COUNTERS, 0/9999 2-3/4 inch x 1-3/8 inch x 1-7/8 inch, No. C1 ZA/CAN 4642

A little bit more chassis cleaning has been done. The current project was to get all the oily soot off the phenolic board directly behind the two COUNTERS, and the two COUNTERS themselves.

The board is now done and the left hand COUNTERS. I have about half of the right hand COUNTERS to complete. It nice to see that when the small windows on the two COUNTERS were cleaned, the numbers went from a dull yellow, back to their original bright white look. I was hoping, but not totally certain, that would happen. They look to be well-sealed units, but one never knows what time and hostile conditions can do to things.

I do find these COUNTERS are VERY jumpy, for lack of a better word. The slightest movement of the assembly starts the dials turning. It takes a bit of patience to get the right side assembly in its correct position for mounting to the front panel. At that point the dial comes nicely to all zeros. It is going to be a very careful reinstall when the time comes.

Because these COUNTERS are so sensitive to movements, I am thinking they must have been assembled and shipped from the manufacturer, with some sort of retaining clip, or block, fitted to prevent any dial movement until they were installed on the Sender, and said clip, or block, was only removed once the COUNTERS were properly in place.

David
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COUNTERS, 0:9999  ZA:CAN 4642 13.JPG  
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  #310  
Old 08-05-20, 02:48
David Dunlop David Dunlop is offline
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I spent a slow, and reasonably careful (more on that later) morning today, cleaning up most of the Sender chassis interior. The sequence of soapy water toothbrush scrub, gentle air gun towards strategically placed paper towels, mild cleaner scrub with toothbrush, rinse, and air gun, is tedious work, not to forget mention of careful drying with Q-tips and more air gun, but the end result is rather pleasing when done.

If you scroll back to the second photo in Post #207, you will see the before image. Oily carbon soot everywhere. Now the phenolic boards are all shiny brown. I can actually see the colour traces in the main wiring looms. The colour code rings on the vertical stack of large resistors can been clearly seen again and all that scary carbon deposit is finally gone from the two large ceramic terminal plates and the rest of the BAND Selector Switch assembly. I will wait until just before reassembly to clean all the switch and relay terminals with DeOxit.

A few more items in the chassis remain to be cleaned, but I am finally over that particular hump and the remainder needs a bit more careful study of how best to position the Sender chassis, while in a disassembled state, to get safest access to the parts that still need attention for cleaning.

David
Attached Thumbnails
WS No. 52 Sender 47.JPG  
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  #311  
Old 08-05-20, 03:33
David Dunlop David Dunlop is offline
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Default COUNTERS, 0/9999 2-3/4 inch x 1-3/8 inch x 1-7/8 inch, No. C1 ZA/CAN 4642

I mentioned in my last posting the cleaning process today on the Sender chassis was almost uneventful. Well here is what I discovered about the word ‘almost’ today.

Back in Post #280 and Post #281 I had discussed what I had learned up to that point in time about the COUNTERS Coupling Assemblies used in the COIL, Aerial Tuning and Senders PA LOADING Drives respectively. The assemblies used in the Sender are more sophisticated, utilizing a lower Bakelite plate with small pin, and an upper tapered metal plate with a slot the pin slid into. There was also a somewhat mysterious SPRINGS, Coupling Assemblies wrapped along the top surface of the tapered metal plate and snugged up against the pin from the lower assembly. It was clearly there to provide some tension to the assembly, thereby taking up any play, or slack in the coupling, but it seemed a bit to vulnerable to any excessive movement. My hunch, in all respects, was correct.

With the Sender now resting on its back on the worktable and the bottom towards me, I now needed to access the top of the Sender chassis for cleaning. A simple enough thing to achieve I thought. Just carefully lift the Sender, turn it 180 degrees, and lower it back down with the top now towards me. The detail I forgot in all this was I had removed the two small wooden blocks from under the two COUNTERS assemblies to gain access to the phenolic board behind them for cleaning. As I lifted the Sender up from the supporting 2 x 4s on the worktable and started to turn it, I saw the right hand COUNTERS assembly dip down and swing suddenly. That was alarming enough, but at the same time I heard a very heart stopping ‘TWANG! Tinka-tinka-tinka-tink’, and then silence. By now, the right hand COUNTERS was actually touching the Bakelite below it and the two parts of its Coupling Assembly were clearly no longer aligned with each other. I carefully set the Sender on the carpet and looked for small SPRINGS, Coupling Assemblies that was no longer in place. It was not in the chassis. A first look at the top of the worktable showed nothing, but when I moved the two 2 x 4s, there it was, resting up against the edge of one of them.

The good part of this event was I discovered once the SPRINGS, Coupling Assemblies is removed from the system, the COUNTERS assembly with the attached upper metal coupling plate can be lifted free from the lower plate. That provided a great cleaning opportunity, once my heart rate had returned to normal. I knew this particular LOADING Coil was snugged back to its zero point, so all I had to do was turn the COUNTERS back to all zeros and remount is aligned to its lower plate and replace the SPRINGS. That newfound knowledge means the other COUNTERS will be able to be reset to Zero far more easily than I have thought, when the time comes.

I added a photo of the top plate of one of the COUPLING Assemblies showing the end with the pin sticking through and the SPRINGS against the side of it.

I am sure this will not be the only heart stopping moment in the restoration journey of this 52-Set, but as long and none of the others involve high voltage/amperage, I will be a happy man!


David
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COUNTERS, 0:9999  ZA:CAN 4642 14.JPG  
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  #312  
Old 10-05-20, 21:38
David Dunlop David Dunlop is offline
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I got another bit of cleaning in the Sender chassis done this morning, deep in the lower back section and was able to bring the Sender Tuning Selector Switch back from beneath its cover of oily soot. I was amazed to find the Switch Plate was marked with luminous green paint. I would have thought it was far too dark in that location for such paint to work, unless there is enough glow from the surrounding valve filaments to keep the paint active.

David
Attached Thumbnails
WS No. 52 Sender 48.JPG  

Last edited by David Dunlop; 11-05-20 at 16:03.
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  #313  
Old 11-05-20, 05:31
David Dunlop David Dunlop is offline
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I was able to pick up another piece for the Project today.

David
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3.8 Litre Mason Jar.JPG  
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  #314  
Old 18-05-20, 17:48
David Dunlop David Dunlop is offline
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Default TERMINALS, Aerial, No. C1 ZA/CAN 4716

A small bit of work done on the Sender this passed weekend, but highly productive.

I was able to successfully remove the two tubular rivets securing what was left of the TERMINALS, Aerial, No. C1 mounting plate to the Sender front panel. If you refer back to Post # 302, you will see the three mount fragments and the back end of the two rivets. The second photo in Post # 308 shows the two truss heads of the rivets from the front of the panel.

I lined the table of the drill press with an old face cloth to protect the front panel paint and went with a 3/16-inch drill bit to cut back the cinch ring on the back of the rivet, being sure to stop the cutting before the centre of the bit got too close the brown phenolic mounting plate.

It was important to be able to identify these rivets to source proper replacements, so once the ends were cut back sufficiently, I switched to a 7/64-inch drill bit to use on the drill press as a punch pin to try and press the rivets out of the front panel. I was a bit wary of this, as generally speaking, drill press spindles are not built to handle that kind of excessive load, unlike a milling machine spindle. But with some gentle increase in pressure, out they both popped.

Before I had started this work, I had assumed these two rivets were plated brass. As the drilling phase progressed, however, the shavings kept coming up bright, shiny, silver. Once the rivets were free, a quick check with a magnet showed they were actually steel. That was a bit of a surprise as I was expecting aluminum.

In any event, they spec’d out to be truss head tubular rivets, with a 7/32 –inch diameter head. Shank diameter is 1/8-inch. Original length was no less than 3/16 –inch and no longer than 7/32-inch. From what I have read on this style of rivets, length is critical to get the job done without damaging parts being held together.

I am going to go with aluminum replacements, as they are the easiest to work with. Particularly when holding thin brown, phenolic board without crushing it to pieces and I only have one replacement available to work with. As it turns out, I can source sizes at both ends of the possible range I came up with exactly, as well as a 7/32-inch length in the middle of the range. I will order in a selection of each.

Now I just have to find an inexpensive hand tool for setting these rivets. The most promising I have seen so far is a C-Clamp style to tool with several interchangeable heads. I will likely only ever use it a half dozen times or so, so don’t need to break the bank There are some countersunk head tubular rivets I need to replace in this 52-Set Project as well, so I need to look into those next.

David
Attached Thumbnails
TERMINALS, Aerial, No. C1 ZA:CAN 4716 j.JPG   TERMINALS, Aerial, No. C1 ZA:CAN 4716 k.JPG  
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  #315  
Old 21-05-20, 22:28
David Dunlop David Dunlop is offline
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Default AERIALS, Horizontal, 4-Section ZA/C 00087

I found one of these a little while back and it arrived in this afternoon's Mail. a lot more compact in real life than I had imagined for some reason. Would have been nice if the Aerial itself had survived, but I think it might be a relatively easy item to replicate down the road.

Now I just need to find the matching Reels, Cable No. 2 Mk II to go with it.

David
Attached Thumbnails
AERIALS, Horizontal, 4-Section  ZA:C 00087 1.JPG   AERIALS, Horizontal, 4-Section  ZA:C 00087 2.JPG  
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  #316  
Old 08-06-20, 03:20
David Dunlop David Dunlop is offline
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Default TERMINALS, Aerial, No. C1 ZA/CAN 4716

I have been side tracked for the last couple of weeks with the discovery and purchase of a minty Tektronix Type 500A Oscilloscope Cart for the Type 545A Oscilloscope I restored earlier this year. Quite nice to be able to glide the 65 pound scope about the shop now and not have to carry it anymore.

With that out of the way, I was able to return to sorting out the shattered AE Terminal Board on the Sender front panel. Once I had drilled out the two rivets holding the remains of the original board to the front panel, I was able to measure the PCB board bits and found them to be 1/16 inch thick and was able to get an old terminal strip of this thickness from a friend in town.

With the terminals all drilled out of the donor board, I was able to scribe out the dimensions of a replacement for the Sender AE Terminal: ¾ “ x 1-1/4 inch. A 5/32-inch hole was then marked out at the centre of that board, and on either side of that hole, a 1/8-inch diameter hole, balanced on 7/8 inch centre to centre.

I drilled the holes out first while the larger sheet of PCB was easier to work with, and then used a 40 tooth per inch X-Acto back saw I bought years ago for a 1/6 Scale Tiger Tank RC Model project, to trim out the required board. Smoothed up the edges and holes with a set of X-Acto Needle Files purchased for the same RC project and another restoration task ticked off the list.

David
Attached Thumbnails
Sender AE Terminal Board 1.JPG   Sender AE Terminal Board 2.JPG   Sender AE Terminal Board 3.JPG  
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  #317  
Old 09-06-20, 18:13
David Dunlop David Dunlop is offline
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Default Receiver AE Terminal Board and Hardware

Thought I had better document this little bit of information before moving on, as it relates to the countersunk rivets used in the 52-Set, which are not catalogued in the Parts Listings.

I had initially hoped to be able to salvage the AE Terminal Board from the front of the parts receiver I have available and cut it down to make the replacement for the broken board on the Sender front panel. I knew the AE Terminal Board on the receiver was fastened with countersunk rivets, which I was going to need specs for in any event, as the same rivets were used to mount the Airloc Cowl Fastener Receptacles on the receiver, and the right side one on my Main Set Receiver was broken.

Removing the panel holding the Receiver AE Terminal Board was easy enough, as was drilling out the four rivets holding the board to the panel. It was at this point, however, I confirmed the board would not work at all on the Sender front panel, even if a correctly sized piece could be cut from it. The rivet spacing on the receiver board was on 1-inch centres. The Sender board needed only 7/8-inch centres. Also, the board on the receiver is subject to a lot more stress and strain than the Sender board. The receiver board holds a Gas Discharge Tube clip on the upper terminal and the large conventional aerial socket on the lower terminal that requires a lot of direct in and out push/pull force. Hence, a 3/16 inch thick board was used here, rather than the 1/16 inch thick board on the Sender.

The good news out of all this, however, was that the four countersunk rivets were retrieved and spec’d out.

These turned out to also be mild steel with a 1/8-inch diameter shank. The countersink is 90 degrees, and the head diameter of the rivet at the flat is 0.220 inches. The length for these would have been ¼-inch, but other lengths were used due to differing thicknesses of material things were fastened to on the set.

David
Attached Thumbnails
52-Set Receiver AE Terminal Board 1.JPG   52-Set Receiver AE Terminal Board 2.JPG   52-Set Receiver AE Terminal Board 3.JPG  
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  #318  
Old 13-06-20, 04:29
David Dunlop David Dunlop is offline
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A bit of a milestone has now been reached with the work on the 52-Set Sender. I have done all the cleaning I can now with the chassis resting on its back. One small section of the lowermost chassis stills needs to be cleaned – the area surrounding the socket for the 813 valve – but I cannot easily access it until the chassis is returned to its upright position. This, however, cannot be done with all the components normally secured to the front panel, flopping around loose.

Fortunately, I still have the three Flick Drive assemblies to continue dismantling for cleaning and repainting of the Indicator Flags on each. Then it is a case of cleaning and polishing the front of the panel to get it to a point it can be reassembled to the Sender chassis.

An interesting observation at this point should be made though, regarding the Flick Drives used on the Wireless Set No. 52.

I do not think calling these Flick Drives a ‘Standard Feature’ on wartime British wireless equipment is entirely warranted, but they were certainly common to many wireless sets, and they appear to have worked reasonably well up to the time the Wireless Set No. 19 came into service, and the shear numbers of 19-Sets in use, quickly revealed the limitations of these drives. The design was sound, but the products chosen for assembly, quickly proved wanting.

The main problem that came to light by 1943 was that with high usage of pre-set Flick Frequencies, the drives eventually began to fail to return to the chosen frequency reliably. In fact, they would start to drift off the pre-set frequencies so badly, renetting to the required frequency became the only way to get the set back where it was supposed to be. The answer for that with the 19-Sets was the introduction of the Crystal Calibrator unit developed by Canadian Marconi.

In developing what became the Wireless Set No. 52, Canadian Marconi built the Crystal Calibrator designed initially for the 19-Set into the Receiver of the 52-Set. And they went further. In reviewing the concerns raised by the Flick Drives loosing the ability to return to their pre-set frequencies with the 19-Set, two problems were identified.

The BUSHES, Dial, Mounting, No. 2 (ZA 14552) were made of machined, cast zinc. This was found to be too soft and wore out easily with prolonged, repeated use. Canadian Marconi switched to a bronze alloy for these BUSHES on the 52-Set.

The second problem was found to be with the two small BRACKETS, Supporting, No. 1 (ZA 14553) located at the outer, upper corners of the Flick Drives. These had typically been made of small folded steel pieces, screwed to the back plate of the drive. In turn, the front panel of the wireless set was then screwed to these small brackets. It was too easy to strip any of the screws in these assemblies, and the sheet steel flexed too much. This combination would eventually allow the Flick Drive to move as a unit behind the panel when flicking between the two pre-set frequencies. Canadian Marconi solved this by switching to solid bronze alloy BRACKETS, welded in place on the Flick Drives intended for the 52-Set.

A third problem was found to be the steel used in assembling the Flick Drives was too soft. CMC upgraded the specs for the steel they used in their Flick Drive Production.

One extra step CMC undertook was to include the FREQUENCY ADJUSTMENT Control directly above the Tuning Dial on the 52-Set Receiver, just in case a pre-set flick frequency was not spot on when returned to, adjusting that Control would find the correct frequency quickly for the Operator.

The attached photo shows the Bronze alloy BUSHES readily on the three Flick Drives and the triangular plated bronze alloy blocks mounted in the upper corners of the drive assemblies.

This is why the manuals for the 52-Set point out that although the drives and parts thereof are common to both the 52-Set and the 19-Set, 19-Set parts should not be used because they are of inferior quality.

David
Attached Thumbnails
WS No. 52 Sender 49.JPG  

Last edited by David Dunlop; 13-06-20 at 22:48. Reason: Fixing the free thinking auto correct.
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  #319  
Old 18-06-20, 23:12
David Dunlop David Dunlop is offline
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I spent the morning today disassembling the rightmost Flick Drive assembly…to a point. A pause was then required for some serious reflection.

The two Flick Indicator Flags at the top of each Flick Drive Assembly need to be repainted. The easiest way to do that would be in removing them from the Drives. The problem, when I got to that point, is the two screws securing the Indicator Flags and their host of assorted springs are impossible to get at with even the smallest screwdriver, without removing the components immediately above them. Something I am just not prepared to do.

The leftmost Flick Drive has little directly above it, but what is there cannot be removed. Mainly the lower Cowl Fastener Receptacle assembly that is welded to the chassis.

After studying the problem for a while, I decided it would be possible to carefully cover over the entire front chassis of the Sender, leaving just the six Flick Indicator Flags exposed. In that condition, they can all be stripped of the existing damaged paint and completely repainted. So a huge amount of additional physical disassembly work can be avoided at the expense of slightly more prep work for the actual painting. I got away lucky with that one.

The other noticeable thing coming out of the Flick Drive pieces today was how different the metal pieces look when clean, compared to the corresponding parts in a 19-Set. They are not the usual dull grey Cadmium Plating one is accustomed to, but a rather shiny finish. Clearly different plating has been used (if one was used) and this may be a reflection of CMC’s decision to use a higher grade of steel in these Flick Drive parts compared to what had been used in the 19-Set items.

David
Attached Thumbnails
WS No. 52 Sender 50.JPG  
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  #320  
Old 21-06-20, 19:46
David Dunlop David Dunlop is offline
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This 52-Set is never short of surprises, large and small.

I have now finished cleaning all three Flick Drive Assemblies on the Sender today. The surprise this time around was fortunately a small one, but interesting none the less.

When I got to the Frequency Dial Drive on the far left side of the Sender and was removing the Lower Flick Arm, I noticed for the first time that it was different from the other two Lower Flick Arms. And from all other five Flick Arms for that matter. They are all the same, just mounted differently if being used as an Upper or Lower.

A closer look at the odd one confirmed it was actually a Flick Arm from a 19-Set. In the first photo attached, you can see the subtle difference. The 19-Set arm is on the left and the 52-Set arm on the right. The difference is in the extreme left tip of the arm.

As you can see, the tip of the 19-Set arm is stepped down from the last mounting hole to the end. On the 52-Set arm, the lower edge of the arm runs full length to the end curve and is cut back at an angle at the top end.

With the 19-Set arm installed, the end of the arm stuck out slightly beyond the edge of the Upper Drive Disc. I do not think this would create any problems in doing so. It might be a different matter, however, if a 19-Set arm was installed as an Upper Flick Arm in a 52-Set. That end-mounting hole near the tip is actually fitted over the central Flick Indicator Flag Spring Hub and the tip plays a role in activating the Flags by means of applying tension to the Indicator Leaf Springs. Different tips would end up applying pressure on these springs at different points and times. I was not interested in exploring that any further, so removed the Lower Flick Arm and Spring assembly from my spare receiver and installed it onto the Flick Drive in the Sender.

Now I have to decide if the Sender Blower Door is the next restoration step, polishing it back to an acceptable paint patina, or switching over to finish fine tuning my recently assembled, new band saw so I can cut the pine boards needed to restore the missing partition in the 52-Set Tool Box.

David
Attached Thumbnails
Flick Arm Comparison 19:52-Sets.JPG   WS No. 52 Sender 51.JPG  
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  #321  
Old 26-06-20, 22:42
David Dunlop David Dunlop is offline
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Default BOXES, Tool, No. 1 WS Cdn No. 52 ZA/CAN 4727

A little bit of a ‘step back’ from the 52-Set Sender this week. The work was at a logical point for a break and I needed to get a few things completed in the garage to continue with the overall project. That work was mainly final adjustments on the band saw I had assembled earlier, and bolting down the bench belt sander and giving it final adjustments as well. It was cool this week and it made sense to get those things out of the way. With that work being done, I decided to get back into the 52-Set Project by backing up a bit to work on the wooden Tool Box again.

I had not done much with the tool box since obtaining it from Jordan Baker, way back around Posts 60 to 65, other than sorting out the specs for it and what was missing from it. Basically, just two pieces were missing, the wooden partition inside and one metal bracket. I had worked out the details for both pieces and realized the partition would be something I could tackle easily enough.

The partition was assembled from solid. Clear pine boards, one half inch thick. It spanned the width of the box at 6 inches and was four and three quarters high. It formed a space at the left end of the box exactly 3 inches wide that was used to hold the cord for the 12 Volt DC soldering iron. The handle of the iron rested on the front top of the partition and the tip of the iron in the small metal bracket that was still in place at the front right side of the box, four and three quarter inches up off the floor of the box.

The challenge was that one half inch thick boards cannot be had these days Best I could find was three quarter inch clear yellow pine, seven and a quarter inches wide, so I bought a two foot length to work with. I marked off an eight inch wide piece (building in a Goof Factor) and split it in half lengthwise. This gave me two pieces of board that I could work with in the band saw when it came time to trim the thickness down to one half inch. Once trimmed, I glued the two pieces back together, let them set and then sanded down the rough bits on the cut side and finally trimmed the piece to the required 6 x 4.75 inches.


David
Attached Thumbnails
WS No. 52 Cdn, Box, Tools E.JPG   WS No. 52 Cdn, Box, Tools F.JPG   WS No. 52 Cdn, Box, Tools G.JPG   WS No. 52 Cdn, Box, Tools H.JPG   WS No. 52 Cdn, Box, Tools I.JPG  

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  #322  
Old 26-06-20, 22:45
David Dunlop David Dunlop is offline
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Default BOXES, Tool, No. 1 WS Cdn No. 52 ZA/CAN 4727

Once I had the finished piece cut, I lightly sanded the top two edges to match the profile of the existing wood pieces in the box, as they have had 70 years of wear on them to soften the edges somewhat. Then it was a test fit that was delightful!

I then applied a single coat of the paint I had matched at RONA, by hand, both sides and top edge. I left the two ends and bottom of the partition unpainted to preserve an original look. The factory paint was applied after assembly of the box. I was not too worried about thin spots showing in the paint as the rest of the interior has some wear spots thinning the paint out a bit in a few locations, so it blends in better.

I had to think a bit about the best way to reinstall the partition. I assumed a 3-inch spacer block was likely used at the factory to quickly get the partition placed correctly at the left side of the box, so cut a 3-inch section of 2 x 4 to serve the same purpose.


David
Attached Thumbnails
WS No. 52 Cdn, Box, Tools J.JPG   WS No. 52 Cdn, Box, Tools K.JPG   WS No. 52 Cdn, Box, Tools L.JPG   WS No. 52 Cdn, Box, Tools M.JPG  

Last edited by David Dunlop; 27-06-20 at 17:09. Reason: Correcting Auto Correct.
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  #323  
Old 26-06-20, 22:47
David Dunlop David Dunlop is offline
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Default BOXES, Tool, No. 1 WS Cdn No. 52 ZA/CAN 4727

The nails used to fasten the partition were ¾-inch finishing nails. I initially though they might have been countersunk and filled, but after a bit of close study, realized they were simply hammered flush with the outside face of the box. Three nails were used front and back. One roughly centred and the other two about one half inch in from the top and bottom of the partition. The original holes were still visible, but filled with years of dirt and oil. This came in handy.

I pre-set the six nails to a point just before they poked into the interior of the box. This allowed me to easily set the partition up against the wooden spacer, ensure the partition was square in both directions and then hold it in place while lightly tapping each nail just enough to capture the partition. I could then easily remove the spacer block and run each nail home. I then used a flat punch to make certain each nail was flush with the exterior of the tool box.

David
Attached Thumbnails
WS No. 52 Cdn, Box, Tools N.JPG   WS No. 52 Cdn, Box, Tools O.JPG   WS No. 52 Cdn, Box, Tools P.JPG   WS No. 52 Cdn, Box, Tools Q.JPG  
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  #324  
Old 01-07-20, 20:21
David Dunlop David Dunlop is offline
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Default Flick Indicator Flags

The process of isolating the three sets of Flick Indicator Flags on the front of the 52-Set Sender has now been completed, along with the related masking of the entire chassis for the ensuing work.

I split a pair of printer paper sheets in half length wise and centred two 5/8-inch slots one and a half inches apart to slide over each set of flags. When the three sets were so covered, I simply added larger sheets of packing paper over the front and sides of the chassis with masking tape.

This way, as I remove the old paint from the faces of the flags, the paint bits will be accessible for clearing away with a small battery vacuum I bought years ago to clean computers and never used. Everything is then also ready for the application of the flat white, flat black and luminous paint back onto the six flags.

David
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Flick Indicator Flags 1.JPG   Flick Indicator Flags 2.JPG   Flick Indicator Flags 3.JPG  
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  #325  
Old 04-07-20, 23:33
David Dunlop David Dunlop is offline
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Default Flick Indicator Flags

Three of the six Flags have now been cleaned of old paint. These were the three in the worst shape. The second from the left looked pretty good at a distance, but when up close, the paint looked suspiciously lifted.

I used a pair of Exacto blades to remove the paint. one is a s thin chisel head, and the second a long slim pointed blade. The paint pretty much popped off all of them and you can see where the paint had indeed lifted on the second one from the left. Darker oxidation of the metal is readily visible.

This procedure has also confirmed the original steps at the factory for painting these Indicator Flags. The full flag face was first painted flat white. The bottom halves of each flag were then given a coat of flat black. The final step was to return to the upper white sections and give them a final top coat of luminous green paint.

David
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Flick Indicator Flags 4.JPG  
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  #326  
Old 05-07-20, 20:13
David Dunlop David Dunlop is offline
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Default Flick Indicator Flags

The flags have now all be cleaned and received their new coat of white paint. I have used KRYLON Satin White #42420, my 'Go To' for flat white paint.

I slipped a small square of Post It Note paper under each pair of flags before spraying them. This paint sets up to the touch in about 15 minutes and I did not want the flags sticking to the mask paper underneath them, as I still have the flat black and luminous paints to apply. The best solution, therefore, was to slip the temporary papers under the flags and pull them out when finished spraying. Any paint sticking to these papers would not adhere, so I end up with nice clear edges on the flags.

This paint take 7 days to cure to a chip proof state, so the flat black will be applied next weekend.

David
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Flick Indicator Flags 5.JPG   Flick Indicator Flags 6.JPG   Flick Indicator Flags 7.JPG  
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  #327  
Old 12-07-20, 00:35
David Dunlop David Dunlop is offline
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Default Flick Indicator Flags

With some available free time today, I managed to get the masking of the Flick Indicator Flags for the flat black coat of paint sorted out and the painting done.

The flags are 13/16 inches long, split in the middle with the flat black paint being applied to the bottom halves. I decided to go with cut down strips of Post It Note paper again to mask off the upper halves of the flags. Once in place, I augmented them with small pieces of painters tape to ensure the guide edge for the paint stayed put when hit with the spray paint spray.

I measured back 13/32 inch from the glue end of each Post It Note and penciled a line across the top of a 3-inch square note. Then cut each note in half to form a pair of masks for each set of flags. Using the pencil line to line up at the top of each flag, I pressed them home and them did the painting tape thing to keep them all down.

Again, KRYLON is my go to paint and I was using their Satin Black #48823. About 10 to 15 minutes after the spay work was done, I removed the Post It Note masking, leaving just the original paper set down before starting work on the flat white paint earlier. Again, it will take about a week for the flat black to cure hard and then I will be able to do the hand application of the luminous Natural Green paint over top of the flat white upper sections of the flags.

David
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Flick Indicator Flags 8.JPG  
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  #328  
Old 12-07-20, 01:25
Chris Suslowicz Chris Suslowicz is online now
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You're making a beautiful job of this restoration.

Chris.
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  #329  
Old 12-07-20, 02:08
Bruce Parker Bruce Parker is offline
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Quote:
Originally Posted by Chris Suslowicz View Post
You're making a beautiful job of this restoration.

Chris.
Agreed!! And a factory fresh example is going to put my yellow cigarette stained one to shame.
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  #330  
Old 12-07-20, 16:28
David Dunlop David Dunlop is offline
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Thank you for the kind compliments, Gentlemen.

This is certainly a much slower, planned process than anything I ever did with the 19-Sets years ago. Lack of comprehensive overhaul information being the major culprit.

Sometimes you can get lucky with tobacco smoke, Bruce. I have had wartime, original pieces from time to time that cleaned up beautifully with mild soapy water. The pail of water and cloth were brown when done but the paint immaculate. Then you get the bits where the organic mix of compounds in the top coat varnish had a mind of their own over the years and heat, UV rays, and chemical interactions between all the varnish components, yellows the coating completely through. That is what I am going to be up against here with the Sender front panel. Lots of careful polishing ahead sooner or later. In the meantime, I am finally getting a good handle on the factory parts that never were varnished and would stay gloss Navy Grey their entire lives. A slow process as well, but finally starting to make sense of it all.

Best regards to all!

David
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