[doctormap]

I sold my 37-620 Philco when we moved (I'm sorry now) and now I have purchased a 42-380. The cabinet looks nice, but the electronics will need work. I'm replacing a couple tubes and doing some general cleaning, but I have a couple general questions:
1.  The knobs seem to be correct but they fit very loosely. Is something missing?
2.  When I try to use the AM tuner the cord slips on the spindle in some positions and then sometimes it slips off the tuner.
3.  Is there a good electronics cleaner to use on the tuning capacitor?

[DaleHCook]

I suspect that you have a dial stringing problem. Did you check the stringing diagram? What kind of dial cord does it have? Does the tuning capacitor turn easily?

[doctormap]

According to the diagram, the cord appears to be strung correctly.
Is there a way to keep it from slipping when I turn the knob?
It has two turns around the knob spindle.
I really don't know what kind of material the cord is made of, it seems to be the original one.
Why do my knobs fit so loosely? Are they incorrect for this model?

[David]

I have never worked on a model 42-380 but will make some suggestions. If there is a spring on one end of the cord is it providing tension? If so try putting something sticky on the string ie rosin.Please post pictures of the set we like pictures. David

[DaleHCook]

I really don't know what kind of material the cord is made of, it seems to be the original one.

David addressed the spring, and the use of rosin. The best rosin is that intended for musical instrument strings - if you have any musical instrument dealers, check with them. Online, the best flux is also sold by musical instrument dealers. You want something in solid form, which is generally preferred to paste or liquid. As for the cord, the manual does not specify what was used. The 1942 Philco parts catalog offered a thinner black cord, and a thicker white cord, but their diameters are not specified.

Why do my knobs fit so loosely? Are they incorrect for this model?

Knobs are generally held in place with one or two set screws, or with a flat spring which goes between the knob and a flat on the shaft. AFAIK, 1942 Philco knobs all used set screws. A good photo/photos of the knobs, and a description of their material, will help us to determine if they are the original knobs.

[Arran]

If the dial cord is original, or an older replacement, the cord is probably stretched, even if it is routed correctly. If the cord is not rotten, which many are and will snap if you pull on them too hard, then you can add an extra turn, or half turn around the shaft the tuning knob goes on. Most people seem to be terrorized by the prospect of stringing dial cords, which is where these short cuts like rosin come from, I am not, so my inclination is to just replace it along with the paper caps. Fly line backing, used in fly fishing, is a reasonable substitute for dial cord, it's sold in sporting goods stores, the ones that sell fishing rods, and lures, and even Walmart. Fly line backing is rated for tension in pounds, 30-40 pound test is more then strong enough.
The original knobs did not use sets screws, they were push on knobs with a steel spring, the repro ones may or may not have set screws, which many annoyingly do as if they are accurately molded from an original knob there is a slot in the back to accommodate the spring. My 42-327 has similar knobs but they are Bakelite rather then Tenite, the latter is what the 42-380 used in the knobs, which is why many or distorted, or crumbling today.
Regards
Arran.

[David]

If you need to replace the dial cord look for some dacron fishing line 50-80 lbs works great. David

[DaleHCook]

The original knobs did not use sets screws, they were push on knobs with a steel spring

I have seen cases where knob springs needed to be replaced. I have some of the G-C replacement knob springs, in a variety of sizes.

[DaleHCook]

Something else just occurred to me, and is another reason why we need photos of the knobs. It is possible that the OP's knobs have the wrong springs, making them loose. I probably have at least a dozen different types of knob springs in stock.

[madsowry]

I've done 3 42-380s. The dial string will come off every time if the rubber gromets are worn out on the tuning cap. It makes the tuning cap be on an angle which makes it easy for the dial string to come off the pulley. New gromets are needed and I've gone so far as to bore out the screw holes that hold the tuning cap so the dial string does not flip off the pulley. You have to do what ever you can to make the pulley perpendicular to the dial.

[DaleHCook]

The dial string will come off every time if the rubber grommets are worn out on the tuning cap.

Do you know the dimensions of the grommets? I have a wide variety in stock. If the OP cannot find the right ones locally I will mail him a set.

[madsowry]

I think they are 3/8" ID with 1/4 " toward the tuner.