[KB1PKS]

I'm seeking help on a troublesome persistence of sensitivity loss and /or completely cutting-out of reception when touching the tuning knob on my 1936 Philco Model 60B Cathedral. Just a little giggle on the variable capacitor tuning shaft can knock out the signal completely, especially on the upper short wave band. Placing rubber grommets and plastic spacers under the variable capacitor helped a little, but not much.
Please see the You Tube video I made at the link below for a visual reference to my issue:
 
https://www.youtube.com/watch?v=f7MoGcZ1Dpw
 
Please, if you've seen such issues before with these early to mid 1930's Philco Model 60 radios and know how to fix them I'd appreciate your help.  Thank you.

KB1PKS  (Bill)