Lots of things getting in the way, so I haven't made a lot of practical progress on the radio, save for a bit of experimentation with toning/staining the cabinet.
The parts hunt, however, is going reasonably well. I sourced an 8" field coil speaker - pretty tricky to find anything original, but the unit I selected is of appropriate vintage and ought be adaptable to the set. A set of valves (tubes if you prefer) has been procured, and a few other items are in. The next step will be some documentation of the chassis, component layout, wiring to filter caps and speaker socket etc,. before the cleanup and recap work begins.
Here's the latest view of the cabinet. Yes, I still need to repair the grill, and will likely work on that this weekend. I have a section of material cut to shape, and on some similar material, tested the wood stains I have and found one that provides a nice match.
Ed;
Don't bother with the wood stain, the only type that works is penetrating stain or wood dye. Shading lacquer, such as what Mohawk or Deft sells, is what they used originally, and will cover up a multitude of sin in terms of stains, and repairs.
Regards
Arran
This weekend allowed quite a bit of time to work on the radio. On the cabinet, I found a few more areas of the delicate grille that were delaminated, and also another couple of weak spots, so set about getting those glued. To repair the missing piece, the repair part was trimmed to match, plus some overlap which was feathered down in thickness. The points where it would meet the rear of the original grill were also thinned. This allowed for the front surface of the repair to be level with the rest, while providing plenty of overlap for gluing in to place. I also carved the details into the repair, to match the design on the other side. This was very fiddly work, but the piece was completed and set carefully in to place with glue, first using tape to allow position to be set, then a clamp on each overlapping joint while it dried. No pictures yet, and anyway, it needs to be toned to match as it sticks out like a sore thumb at the moment. However, on tests I did with some similar material, it will be possible to get a very acceptable match. There is a tiny bit of grille surface to be replaced just adjacent to the repair part - this was near the messiest part of the break and must have fallen apart thanks to the carved details in the top ply - any pieces were long gone before the set came to me, but they can be replicated with a little care.
As there were a few breaks (probably not the best choice of words there...) in the cabinet repairs, I turned to the chassis to get familiar with the layout and wiring. A diagram of the underside was drawn up, and the layout of valves, power supply and major components added. Add to this, details of the speaker socket and filter cap wiring, plus notes on which of the paper caps corresponds to component numbers on the schematic. I find this to be really handy reference material for when the soldering iron is hot. It also helps to notice the clues to the set's history. In this case, there are signs of at least one, probably two visits to the repair shop. Both the larger caps were replaced with Mallory and Aerovox parts, and the latter substituted again with a smaller electrolytic. A few of the resistors look like 50s or 60s replacements as well. One or two repairs were tacked on - and have fallen off their tags on the valve sockets, and in a couple of places, the junction between components is hanging in mid-air. I'll spend more time tracing to make sure there are no mistakes lurking.
The speaker chosen for the project arrived, and should work well enough with it. Field coil resistance is a bit high, but can be paralleled with a resistor to net 100 ohms required. A quick tinker with the unit did not suggest an easy way to remove the coil for a rewind. There is some damage to the cone, which I knew about, and this can be repaired, or I may replace. For now, it is operational, will fit the cabinet, and the transformer is good. A new wire harness and 5 pin plug will be made up for connection to the chassis.
More pics when the grille repair is presentable. I'm still thinking about overall cabinet tone and finish, in particular what are the proper colour choices for the top, sides and bottom molding.
Thanks for the pictures - nice radio. It's also helpful to have your notes on colours.
Usually I try and preserve original finishes, but this one had rather a hard life before being left for dead on the street... Time to learn some new tricks
More progress today, and I think I have the repair to the grill to a satisfactory standard.
Here's the repair piece glued in. Where it joins the vertical bar on the right, I have marked out the carving required. At this point, there was still a littl shaping required to match its counterpart on the other side.
Very carefully, I completed the shaping, and carved the groove details
Then a little stain on the new wood, plus a little shellac, just to see how things are going to work out.
It will never be perfect - or original - but I feel this has turned out well. The damage to this area was something that almost saw me walk away (but of course I couldn't in the end) and so it becomes a challenge. Then again, I have a hard time seeing 80+ year old wonders like this meet their doom.
On the electronics front, things are lining up nicely. There is a full set of valves, and a plug matching the speaker socket arrived at the end of last week. From there I can make up the cable harness. Recapping will be relatively straightforward - The chassis is uncluttered, and quite an economy of components was managed by the designers. I'm thinking perhaps to restuff the paper caps, as there are relatively few to deal with. A closer look is needed to see if any are replacements. The big cans will be restuffed. From pictures, these also ought to have cardboard sleeves, so I'll have to make something to match. Looking forward to the next phase.
WOW ! You did a really beautiful job on that grill repair ! Once stained it is going to blend right in so nobody will even notice. I am good at the electronics, but I will admit I suck at fine cabinet work.
