[Hammarlund] Need help removing set screws in a HQ140X antenna knob.

[Jim Pruitt]

I am trying to restore a very cruddy HQ140X.  It is somewhat corroded and I 
have mostly removed the corrosion/mice surprises from the inner chassis but 
need to remove the front panel and do that and the front of the chassis.  I 
have all of the knobs and nuts removed except the one on the antenna 
trimmer.  I can not get that set screw to turn loose in that knob and the 
knob is plastic/bakelite.  The screw looks a little rusted but in plastic 
that should not matter.  Hitting it while trying to turn it does nothing and 
because it is sucha small wrench it just eventually turns in the set screw. 
I am using allen wrenches and think that is correct.  Or is it spline?  I 
hope not.  At any rate,  how do you get stubborn screws to loosen in plastic 
knobs?

Thank you.

Jim Pruitt