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Radio City Products 423 Restoration [Permalink]

For those who don't know; I quite enjoy buying old broken test equipment and restoring it to a fully working condition. I recently added another ebay purchase to my collection. It's by far the oldest piece I have dating from about 1942. That's about seventy three years old. That's fourteen years older than my AVO 8 (MK1).

It is the "Radio City Products model 423". There is a great site for reading about the history of RCP if you are interested:


As you can see, it got to me in a rather poor state. The top of the box was falling apart, the leather handle had snapped and most of the varnish had disappeared.


The joints at the back of the box were also loose. This is likely to be because the lid puts stress on these joints when it's fully open.

Some other problems also needed sorting. So, The plan was;

The first interesting part was the handle. I don't really know much about making leather carry handles and so I just took the old one to a shop that does leather repair and asked "Can you make a new handle like this?". The result was a handle that had both ends. Hooray! The woman in the shop tried to give it an antique look and finished it with a two tone dye. This is the place I used:


So that wasn't much effort and was only £18. The meter itself from ebay cost £12.59, then there was £16.61 shipping from somewhere in the USA. So far the handle has been the most expensive part, in total I've spent £47.20 on the meter.

Now to the box and to the loose joints. The joints are dovetail joints. I clamped them back into place and then drilled a hole down each one. I then unclamped them, applied glue, clamped them again and put nails in the holes I drilled. I'm hoping that by adding the nails I have increased the life span of the newly repaired joints. You can just about see the nails in the joints in this next photo.


While the lid was off, I took the opportunity to remove the broken plywood.


Wanting something easier to do, I then turned to the clasp, it was a little stiff and a bit out of line. I decided to replace it completely which was slightly more awkward than I anticipated. I wanted to bolt it on instead of screwing it on. It's more secure and more difficult to get wrong. This was easy enough on the lid but the box required some notches to be removed.







Next on the list was that shattered plywood top. This was fairly easy to replace. I cut out a section of ply to roughly the same size as the lid, slightly too big. Then, because the joints on the corners of the lid were also loose, I had to put the hinges back on and attach the front section using the new clasp so that I could hold everything in the correct position to glue it back together. I placed the box upside down on the new ply while I let the glue dry. Held in place with some heavy things I had handy.




Then I just had to trim the excess off and sand it down. The sanding part was made really easy by this magic device...


It rounded off the corners of the lid nicely and powered through what was left of the varnish.



Quick confession, this is the first time I've really been focused on restoring a wooden box. Usually I'm restoring the electronics. I had to ask a friend about what varnish to use. He recommended polyurethane varnish, so I got some in the closest colour to the original. On the inside of the box the varnish hadn't peeled off and so I could match the old colour. I ended up buying some ronseal varnish in walnut flavour.


This next photo was taken after the first coat, I gave it two coats.


With a nice shiny new clasp and handle, I couldn't leave the hinges and the handle holders looking dull and old. Time to break out the astonish and a small handheld rotary polishing tool. I cleaned them up with one of those rotary wire cleaning tools first to get the muck off. See the before and after shots.





That's all the visual stuff done. Now I had to stop the rattling inside the meter coil assembly. After playing the invisible maze game for a while it turned out that there was the head of a screw loose inside. Hmm. Time to open it up a little further. The meter coil housing is difficult to remove because of one particular nut. It's hidden under lots of wiring and is very difficult to access with a tool of any kind. I did get it in the end. Once it was out, I simply removed the back and the screw head fell out. A quick check to make sure everything was still held together correctly inside and then it all went back together.





Hooray, all fixed. Almost. With the new clasp in place, the handle stopped you being able to open the box easily. I had to move the handle clasps down a little. This would have left two rather ugly holes visible so this is why there are two screws that appear to do nothing. The finishing touch was to fill in the white paint on the pointer. It had gone dull and grey and in some spots fallen off.


And now for the before and after photos together...



Bonus shots... (Including the hand drawn schematic found inside the meter, where the batteries go.)






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