So after recapping and repairing 2 table tops (1933 and 1949 RCAs) an a '50 Chevy radio, I decided to try a 40-180. And after removing the chassis, my first question was what the heck did I get into?
I've read a several other threads on similar chassis recaps. And learned a few things along the way. Like restuffing the Bakelite cap pack, and replacing/repairing the rubber coated wires. But I was wondering if there were other tips or tricks to this chassis.
It looks like the first thing you do is desolder the 7 leads from the series of adjusting screws (I don't know what else to call them) from the push button switches. Then you can remove the bracket. Next it looks like you desolder the bare braided wire from each of the preset coils that runs to the push button switches. After that, it looks like you will then have access to the majority of the caps.
Am I on the right track so far? I did order a set of service papers from philcorepairbench.com and caps I should get from just radios.com that should be showing up later this week. Any other tips for this chassis?
Thanks!
-Nick
Nick
One thing, I think, you have one of those "rubber jobs" where the wiring is done using rubber wires.
It is, I understand, recommended to re-wire all of that using modern cloth-covered wire.
Rubber is probably cracked now and will be getting more cracked every day.
Yeah, I'm aware of the rubber coated wire issue. I've read other people's comments about it. Surprisingly, every wire except the pilot light's insulation is still intact and fairly flexible. But I'm still leaning towards replacing it, or unsoldering one end and putting shrink wrap over it.
I'm just checking to make sure I'm taking the correct approach to recapping. This chassis intimidated me a little.
Nick, you are on the right track. I am working on my 40-180 right now and have removed all of the caps, the tuning coil, and the dial display. The only thing left on the top of the chassis is the transformer. You can get to all of the caps without removing the tuning coils - just unscrew the bracket and flip it out of the way for now. I have all new caps and resistors at home and am waiting for a delivery of wire so I can begin rewiring. Take lots of pictures, work with the schematic. Make notes. You'll be fine.
Eric,
Thanks for the confirmation. I'm still on the fence about rewiring, vs. slipping some heat shrink over one end of the existing wires. If I go the rewire option, whats a good size? 20ga solid for anything in the chassis, and then stranded for the pilot?
You are doing fine. Heat shrink over wires is OK for isolated instances, but is an eyesore if overdone. Solid wire easier to handle for anything that will not move, otherwise stranded. Try to use the same color as original so you don't go nuts next time you have to dive into the set.
I ordered a "kit" of 6 spools of 20ga stranded wire. Then I looked more closely and found that most everything under the hood is solid core- doh! Oh well. Look around, there are a few places that have very reasonable deals on wire. I found mine here:
http://www.elexp.com/cbl_ld25.htm (though it hasn't actually arrived yet - so don't take this as an endorsement).
As CF mentioned use to same color replacement wire as believe it or not it is color coded. Would use plastic covered wire as apposed to the new cloth covered. If it was an older set from the '30's I'd go with the cloth. Plastic is cheaper. 22Ga is fine.
Terry
I made the same mistake myself, EricS. Most everything under the 42-400 is 20ga stranded now, as opposed to the original 22ga solid! (What was I thinking???). Works perfectly swell, but was a BEAR to connect at spots with multiple point connections. Radio plays beautiful and strong, but that will always be in the back of my mind, gnawing away, till it gets to the point where eventually I'll have to tear it all back apart and rewire it again!
I ordered both stranded and solid. I do not see anything bad about stranded.
AWG 22 is rated for 7A for chassis wiring so even this is overkill, gauges 24 and even 26 would work just fine, save the situation where one winding is used for all filaments then you want some margin on the ampacity and gauge 22 is somewhat warranted.
Good to know 22ga is plenty. I have a lot of 22ga solid laying around (albeit not the same colors as the original, but oh well). I was expecting my caps to show up yesterday, but they didn't. So this weekend I started the desoldering process. I'm rewrapping the old caps back on the terminal. So when the new ones arrive, I know where they go and can quickly replace them. My resistors arrived, so I can start replacing those along with the wiring.
For the power cable, does anyone know what the original was? Was it still rayon covered wire? Did it have a unique plug? Mine was replaced with a generic lamp cord at some point, but I would like to make it look authentic. Also, the white plastic piece behind the dial is filthy (actually, the entire chassis was caked in dirt, I blew it pretty much all off with compressed air). Should I just try washing it with soap and water, or use a mild cleaner with bleach (like Clorox cleanup spray)?
Never. Ever. Use Chlorox. On anything. Other than your food prep surffaces or your kids' stomach bug puke.
I have found GoJo or Goop to be excellent cleaners for lots of different surfaces. It removed crud from the wooden cabinet, from the metal chassis, from the dial glass, from the white plastic behind the dial glass, from the knobs...
I have heard the no pumice version of Goop/Gojo was good for cabinets. I guess I never considered it for plastic too. I'll give it a shot.
yes, no-pumice GoJo.
In fact some people tell that Windex makes things dull, but I have used it on many things, including my fully custom kitchen cabinets, and in 5 years they did not suffer (no, I do not use it too often). For things like dials Windex might work, but I am in the habit of trying it on small inconspicuous area first.
Alcohol works well on many things plastic.