[Hallicrafters] S-53 slugs n' tuning - Slug Fest

[Kevin J. Ward]

Using candle wax is bad advice. I spent many years repairing avionics, 
tube type and transistor, and here's my advice concerning coil slugs and 
wax.

Paper coil forms are usually slathered in beeswax to keep the slugs from 
moving. Here's a tip to make removal or adjustment easier. Hold the 
business end of a soldering iron or gun near the coil form (no closer 
than a quarter-inch) long enough to soften the wax, then turn the slug 
out before the wax hardens. This trick can also be used during alignment 
and will prevent slug breakage.

I keep a lump of beeswax at the workbench for tightening up loose 
slugs.  Use a pen knife to shave a small bit of wax on top of the loose 
slug, then carefully heat the form as before. In all cases, keep the 
iron from actually touching the coil form. And never, ever use candle 
wax. Here's why.

Beeswax is the stuff bees make their honeycombs out of - literally.  
Candle wax is solid paraffin - a hydrocarbon of the methane series. It 
is made from paraffin oil, which is obtained from petroleum. Beeswax 
will remain solid at higher temperatures than will paraffin, and when 
solid is harder than paraffin. Paraffin could soften and run out of the 
coil if your vacuum tube rig gets really hot. Then the slugs would be 
free to move and throw the alignment out of whack.

73,
Kevin  N2IE