I have a '35 Model 60b early version that the tuning condenser shaft is slipping and not sure how to fix it (or if it can be). The shaft turns much too loosely and is not moving the condenser blades except slightly every couple of turns. Obviously, the blades have somehow broken loose or otherwise disconnected from the shaft. Any advice on how to better diagnose and repair would be appreciated. I've not attempted to take it apart yet so I don't possibly damage something. Thanks.
Unfortunately, this is where my ignorance becomes very obvious. I don't know exactly what the vernier drive is, except some further searching I did seems to indicate this is a secondary tuning drive. I may be wrong.
Simply put, there are three shafts on the front of my Model 60 chassis. The middle shaft turns the shadow dial and rotates the blades on the tuning condenser. When I turn the shaft with my fingers, it basically spins freely and only seems to "catch" the blades and rotate them every couple of shaft turns - when the blades should be turning in direct correlation with the shaft turn. It seems something has come loose or broken inside that would have connected the blades to the shaft.
I hope this helps explain my predicament better.
exray - thank you for your reply. If this addition info helps explain, please let me know if you have any additional thoughts.
Be absolutely sure that the bearings and shaft of the tuning gang itself are cleaned and re-lubed and free to move by hand, otherwise the vernier assy. will slip. Old dried/caked grease in the gang shaft is usually always a culprit.
Jay
That rear set screw adjusts the bearing end-play and tension. Use just enough tension to keep the shaft from slopping with good contact.
WD-40 is NOT your friend here. Use a small dab of Lubriplate or other light white grease at both bearing spots. NOT anything automotive, like bearing grease (too heavy) or even plain 3-in-1 oil (it runs away).
Chuck
Okay - Here's what I have. I removed the tuning shaft (only 1-1/2"-2" long) and cleaned/lubricated it. Removed the 3 bearings from the brass shaft/sleeve and clean & lubricated them - as well as cleaned & lubricated the inside of the brass shaft/sleeve. Lubricated the bearings surrounding the brass shaft contained in the condenser frame. Tried to turn the adjustment screw on the backside of the condenser frame and it's completely frozen - tried to lube and free with no success.
Results of the above: 1) The short steel tuning shaft (holding in pic 3) turns very freely but doesn't move the condenser blades at all, 2) Finger turning the brass shaft/sleeve that has the 3 bearings in it turns the blades very smoothly with no slip - as it should.
I'm sorry, I can't figure this out. I see nothing on the end of the short steel shaft (notch, teeth, etc) that should/would engage inside the brass shaft/sleeve to turn the blades. With the adjustment screw on the backside frozen, I'm at a loss as to how to disassemble the entire shaft and clean/lubricate -- but seemingly this would have no effect anyway since the blades turn so smoothly when finger turning the brass sleeve.
No clue what to do here. Any advice would be appreciated. I've attached these pictures in order to illustrate what I'm working with. Note: any white discoloration is the white lube I used and since wiped off the excess. Thanks.
Note from site admin: Sorry, but the photos which were attached to this post are no longer available.
Im not for sure, but perhaps there used to be a rubber-bushing that may have hardened and is missing? If so, try finding some neoprene type rubber hose from a automotive store ( of proper thickness) that will fit snuggly to the shaft to make shafts rotate together. Ive had similar probs with old Atwater Kent sets, and adding the rubber-shaft bushing worked replacing the missing parts. On Philcos, Im not sure tho. The "vernier" is a slow-moving shaft for fine-tuning on the SW bands on most old radios or communications receivers. Once Ron or Chuck gets back here, they will be able to tell you exactly what is wrong. Im just tryin to help with ideas in the interim.
Thanks Texasrocker, I appreciate it. From all of the posts I've seen, I'm surmising that this shaft engages to turn the blades based on spring tension against it's end -- managed by the screw on the opposite end of the condenser. If I'm correct, then the fact that the screw is frozen/won't turn either direction may be the culprit. May be, but it doesn't look like a bushing goes on the shaft the way it's designed and with the 3 bearings it has to fit between. Like you said, I'm sure Ron or Chuck will set me straight! Thanks again.
Most important: Don't lose any of those ball bearings!
As you have the drive disassembled now, what you need to do is thoroughly clean every part; the tuning control shaft, the shaft of the tuning condenser which the shaft fits into, the ball bearings, and the cup which holds the entire thing together on front of the tuning condenser.
Then, as Chuck mentioned, use a good quality grease on all of the parts as you reassemble them. Lubriplate or white lithium are good choices. As Chuck said, not anything automotive.
This will cure the slipping. As for that set screw on back of the tuning condenser...do as Chuck said. Additionally, the set screw should be set so that the plates of the tuning condenser are "centered" and not rubbing against each other.
I've done all of the above as Chuck directed with no luck. Thoroughly cleaned and lubricated everything with white lithium grease and reassembled. The set/adjustment screw on the back will not turn at all in either direction -- it's frozen in place. Unfortunately, I cannot follow Chuck's direction on adjustment of that screw because it will not turn. Pic of screw attached.
Note from site admin: Sorry, but the photo which was attached to this post is no longer available.
One brand name comes to mind...PB Blaster.
Soak the adjustment screw and nut liberally with the stuff. Multiple sprayings over a day or three may be necessary. Be patient. It should eventually break free.
You did loosen the locknut, right?
Hey exray,
It is all frozen up. Screw, nut neither will turn. I followed Ron's advice and have soaked it well to see if it will work loose. I have had some success, though. After 3 thorough cleanings and lithium white lube applications, I now have the shaft engaging the blades in a limited manner. I figure when I get the screw loose, lubed and adjusted, then it will work okay. I've been told I've got a screw loose a few times, for once I wish it was true....
I have rarely needed to adjust the back of a variable capacitor; if the assembly is turning OK and the rotors are not touching the stators, leave well enough alone. But if you must, you could try the following.
Spray first with WD40 and let sit for a few hours. I also give it a shot of De-Oxit too.
Get a very good box wrench to fit the nut. You could also use a properly fitting nut driver but proceed cautiously. It is easy to break the nuts, they are often fragile, and made of brass. After an intimate relationship with rusting iron and mouse pee for half a century or more, they are reluctant to part.
Make sure the wrench fits the nut very well. Then tap the wrench lightly anti-clockwise with a wood stick or small mallet. Do not over do this. Sometimes a tap or two clockwise followed by a few taps the other way will work. If there is a lot of crud and rust afound the nut, you could try to scrape it away with a scalpel or small knife, followed by more WD-40 or machine oil. Once the nut is a little loosened up, you should be able to re-tention the device by turning the screw. Brute force will not serve you well. Everything must be treated with lubriplate or lithium grease before tightening up. I clean everything up with a little paint thinner with a paper towel underneath to soak up the drippings. Of course don't fire up the set for several hours if not overnight after using flammable solvents, and remember to take the trash rags and towels out of the house right away. That and left (other) hand in the pocket has kept me alive so far.
So far as the front bushing is concerned, I don't have a lot of experience there, but there were sometimes rubber bushings to damp the tuning capacitor so that critical tuning, especially on SW bands, would be possible. Kind of like go/no go mechanical couplings. Others would know more than I about these things. But unless there is a gear or idler of some sort, it's a 1 for 1 deal.
From Joes photos, the orig shaft looks pretty worn! Look closely. After getting the "loose nuts" behind the steering-wheel fixed, ( JUST KIDDING!!),& shafts are freed up, stator & plates not touching thru entire rotation of tuning condenser,& making sure both point-to-point shaft surfaces are engaging, if not, some kind of "spacer" is going to be needed for the worn shaft? Just a guess only. Perhaps a single-layer of friction tape on the worn shaft would bring everything together? Not sure tho, Im guessing at best, & the Philco Pros here will know for sure!! I just had to fully replace a tuning condenser on a 40s Firestone Radio with a sub, ( orig chassis had been dropped hard on orig tuning condenser beyond repairs), replacement & match wasnt easy for alignment. You WILL be able to fix this prob Joe!! Plenty help here that knows lots more about specific model Philcos than I do!! Just tryin to help if I can. You sure build very-fine homebrew Loop Antennas indeed!! Just think how good that mod 60 is going to receive once you get everything working!! Best of luck with all your restorations!!