Hard wax on RF coil ferrite slugs
 

Could Otex ear drops dissolve the hardened wax which prevents the fragile slugs from rotating?
The active ingredient is urea hydrogen peroxide (5% w/w). The other ingredients are 8-hydroxyquinoline and glycerol
Not sure if this could damage the coil former.

Re: Hard wax on RF coil ferrite slugs
 

If you heat the slug with a soldering iron just enough to soften the wax I find that works ok
Cheers
Pete

Re: Hard wax on RF coil ferrite slugs
 

I have tried that but it did not work, it's still stuck that's why I'm considering Otex.
It might be damaged or cracked it's difficult to tell but the radio (Phiips 310A) is functional now, I'm not sure if it can be improved upon.
I may well leave it as it is.

Re: Hard wax on RF coil ferrite slugs
 

As a chemist, my instinct is that Otex is not the way to go, but I could be wrong. Are you really sure the stuff is wax and not something else like paint? Waxes tend to have 'modest' melting points.

Can you offer some more details on the formers? Are we talking IF coils, are they plastic or something else, what era are they. As you say, any approach needs to avoid damage to the formers.

Wickes do a paint and varnish remover which I have used successfully to soften various substances with (in the process of cleaning), and I suspect it would soften (real) wax, but I know that it does react with some plastics.

B

Re: Hard wax on RF coil ferrite slugs
 

Philips 310A 1952 S14 coil slug

Re: Hard wax on RF coil ferrite slugs
 

Why don't you get a sharp knife and lift of some of the excess wax which is on top of the can and experiment with it? If it doesn't melt at some reasonable temperature (<100'C), that would be off-putting, tending to suggest it is a material which has set and may need a strong solvent to soften it.

B

Re: Hard wax on RF coil ferrite slugs
 

Never mind moving the stuck slug.
Add another ferrite slug and see if you can peak the coil. Leave it in if that works.
If the output goes down there is a need to reduce the inductance. Introduce a small piece of brass or aluminium rod into the former and see if it peaks, glue that in if it does.
If nothing peaks the coil then the existing slug is in exactly the right place.

This may not work with TV IF coils where the core affects coupling.

Re: Hard wax on RF coil ferrite slugs
 

Curious that on the two transformers to the right, the slugs seem to be on brass screw shafts, but the coil that's highlighted is different.

B

Re: Hard wax on RF coil ferrite slugs
 

Further to reply from John (Sundog) "back in the day" there was a device like a pencil called a Tuning Wand which had exactly what he described ie a ferrite slug at one end and a brass slug at the other.

Re: Hard wax on RF coil ferrite slugs
 

I will try that, now I need to find some bits!