cleaning blocking diode connections

[oldjohnnyb]

I want to clean the stud bolt connections on a blocking diode assembly. They are badly corroded and i'm not sure the nuts will come off. I am proposing to use "Servicol 10". I am concerned that solvent will penitrate the moulding in which the rectifiers are sealed. Has anybody any thoughts. I am reluctant to use "Plusgas" but again any thoughts.
John

 

[ccscott49]

What type of corrosion? Rust? a little plus gas should help that and with careful use so should any other of the same type, if its verdigrise type (copper) a little hot water should help, be very careful, as they could break. If you are careful the plus gas etc, shouldnt damage bthe stuff sealing the box.

 

[oldjohnnyb]

I suspect they are steel with some form of plating.
Thanks John

 

[charles_reed]

Splitting diode connections

In fact a major problem if you have any big (>30amp) currents flowing.

You'll find they're cadmium plated steel.

I now clean mine every year as part of spring fit-out, the ferric oxide acts as a major resistence and causes local overheating.

I've not used WD40 - a little drop of diesel is cheaper and just as effective - and no the insulation substarte doesn't appear to be affected by common solvents.

Clean with phosphoric acid - neutralise and coat with silicone/teflon grease or better copper grease (as is used for anti-squeak in automotive brake assemblies).

Watch out for local damage to the insulation material when you unscrew them !!

Good luck