Re: Revox A77 refurbishment advice please.
First, thank you all for your helpful comments.
Now brakes, on mine I have the shiny metal bands and the brake drums have cotton tape that seems to be glued on. Due to high forces >200 gms needed to turn the drums in the unwinding direction I removed the bands and ran what I thought were clean fingers around them to see if they were OK, the surface seems very hard, anyway I reassembled them and found the force required to turn them was now way too low so bands off again and I cleaned them with Isopropyl alcohol being careful not to over do it, the cleaning cloth I used snagged quite a bit on the hard rough surface. Seems the little amount of grease on my fingers had a big effect and cleaning restored the forces to near normal. Now because the tape liners seem hard and rough they may be suffering from the glue migration problem. Re-adjusting the solenoid to bring band clearance to near 0.04 thou has restored forces to normal but the brakes do seem 'touchy' hence I will replacement the cotton tapes.
The comment about parts not being cad plated is right now I think about it, my thinking was clouded by my familiarity with cad plate from working with it in my aviation engineering career. I have a stock of stainless screws and will replace the bad cases.
I have done a fair amount of research using the forum search facility and have read many threads on the A77. A common theme seems to be replace the small electrolytics, tantalums and motor phasing capacitors, also the trimmers.
I also need a belt for the counter, I can only see one belt in my machine, am I missing one?, Nagravox supply two in their kits an 'O' ring type and a toothed one.
The pinch roller seems good but should I replace that?
Your thoughts on what to lubricate would be appreciated as well?
Now sourcing these parts, Nagravox Australia seems to get mentioned a lot, your thoughts on who to use?
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Andrew
Illegitimi non carborundum
Last edited by MeerKat; 11th Jul 2019 at 11:55 pm.
Reason: more detail
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