Have an old (1948) Sears radio where the dial cord slips on the tuning shaft. Have check the layout and wrapping of the dial cord and spring to make sure the cord is tight, with no help in fixing the cord slipping. The cord is the original, and the shaft is alum. The bushings for the shaft looks to be in good shape with very little side-to-side movement. Any suggestions?

:Have an old (1948) Sears radio where the dial cord slips on the tuning shaft. Have check the layout and wrapping of the dial cord and spring to make sure the cord is tight, with no help in fixing the cord slipping. The cord is the original, and the shaft is alum. The bushings for the shaft looks to be in good shape with very little side-to-side movement. Any suggestions?

David,
Buy a baseball pitchers rosen bag at the sporting goods store and rub it on the dial cord. Lube any bushings/bearings in the tuning capacitor and associated linkage with automatic transmission fluid.

Will

::Have an old (1948) Sears radio where the dial cord slips on the tuning shaft. Have check the layout and wrapping of the dial cord and spring to make sure the cord is tight, with no help in fixing the cord slipping. The cord is the original, and the shaft is alum. The bushings for the shaft looks to be in good shape with very little side-to-side movement. Any suggestions?
:
:David,
:Buy a baseball pitchers rosen bag at the sporting goods store and rub it on the dial cord. Lube any bushings/bearings in the tuning capacitor and associated linkage with automatic transmission fluid.
:
:Will

I haven't tried the rosin technique but I have successfully used the 'glue' technique: rub a little water based wood glue on the cord which will make it sticky and give the cord traction. Don't overdo it, use sparingly

Nick

Three thoughts....considering that the point where the dial cord experiences its very sharpest turn radius, is the typical two to three turns where it encircles the tuning knobs ~1/4 in shaft down within the concave groove that it is wound within. In all probability, with decades of use, that groove has become a highly polished / slick area. Why not consider three possibilities of restoration of that current shaft surfacing to a more appropriate matte finish with mildly longitudinally striated grooving.

The first of two procedures would involve a dimensional "eyeball" sizing of the groove radius and the location of a cylindrical "form" or dowelling of the same dimension or very slightly smaller. Upon that form, a single covering layer of ~#400 wet 'n dry would be placed with any diametrical surplus being crimp retained by your encircling thumb and fingers as they are holding the combo. Next wet down the sandpaper with a trace of dishwasher JOY, etc plus water to attain captive surfactal retention of that moistening combo to the sandpaper AND metal shaft as you then use the combo on it.
The preparation of the shaft is to either loosen up the stringing of the dial cord and move it out of the shafts groove area or if there is adequate spring freedom, the cord might be sequentially nudged backwards as the shaft is rotated such that the cord ends up being out of the groove and resting back on the shaft away from the groove working area.
If you will then start moving the "resurfacing" combo back and forth, front to back , down into and then out of the groove; it should then be possible to rotate the shaft slowly such that you have eventually covered its total periphery. This will then leave micro grooving from front to back within the groove along with its now matte surfacing. This will again provide the nominal "grip" that the virgin shaft initially presented to its encircling dial cord wraps.

A variation of this is to use the pumice charged abrasive agent that is contained within the rubber core of a wooden stick / pencil profiled typewriter eraser. (Eberhard faber, etc,from an office supply store) Expose fresh erasing area on its tip and then use it in the same manner of moving it front to back to produce a matte resurfacing of the shafts groove from front to back. This procedure leaves a slightly less matte surface than the former, but it far exceeds a slick groove condition.

The last and crudest procedure involves the same front to back movement within the groove but it involves either a sharp knife or an #11 Exacto knife with it having a moderate applied pressure and the blade scraping from front to back.
Then one moves aside just enough by shaft rotation, to then enact other sequential scrapings. The end result will be micro front to back striations, side by side, around the periphery of the inner groove.
This, along with proper dial cord spring tensioning, should restore normal positive dial cord rotational integrity. Eventually without reverting to sticky / goo countermeasures.

73's de Edd

First you need to identifiy where the problem is.

DRAG/LOAD:
Is the tuner and the mechanical elememts like the bushings moving freely or binding?
If binding then lubricate properly.

Next if you are comfortable with know the there are free moving parts then test to see if the cord is slipping because it's too loose or whatever.
Sometimes trere are more than one hook on the wheel to clip the spring to to adjust tension.
If everything is fine there you can try various things to add friction to the cord.
I use bees wax or candle wax along the string. Works very well and very easy to apply. Make sure it's coated very well where the action is.

Well, everyone has given me several ideas to try, as well as looking at possible drag/loading by the tuner. I hope this weekend, time permitting to take another look at it.

Thanks,

David S

:First you need to identifiy where the problem is.
:
:DRAG/LOAD:
:Is the tuner and the mechanical elememts like the bushings moving freely or binding?
:If binding then lubricate properly.
:
:Next if you are comfortable with know the there are free moving parts then test to see if the cord is slipping because it's too loose or whatever.
:Sometimes trere are more than one hook on the wheel to clip the spring to to adjust tension.
:If everything is fine there you can try various things to add friction to the cord.
:I use bees wax or candle wax along the string. Works very well and very easy to apply. Make sure it's coated very well where the action is.
: