NAD 3140 amp input selector repair

[dalehimself]

I have a NAD 3140 amp that has been neglected for many years, that I am trying to clean up and use, although there is one critical problem. Behind the input selector knob is a metal shaft about 8" long, that connects to a similar shaft inside the unit near the back. These two shafts were connected by a plastic grooved pressure connector, each shaft simply slides into one end and is help in place by pressure and friction (very much like a Chinese finger puzzle). Unfortunately, from age and use, this connector piece, about 1.5 inches long, is made of plastic, which has dried out and completely crumbled. Is something like this available, or does anyone have a DIY substitute? Thank you!!

 

[planet10]

Shrink wrap of an appropriate size.

dave

 

[Sqeek]

excellent ideal @ planet10 or may i suggest make one out of a wood dowel possible?

@ dalehimself i am curious of what you speak could you post a picture ?

Happy Holidays

 

[dalehimself]

First picture, just about dead center, you can see the two metal shafts that have to be coupled. Second picture: you can see the shaft that needs repair, and the one to the right of it that is still intact, with the black plastic coupling. I'm thinking the way to go is going to be a piece of wood (or plastic?) dowel rod drilled out just large enough for the two shaft ends to be wedged into. I could possibly add some glue and/or saw dust just before I'm ready to finally fit them together.

 

[PRR]

1/4" fuel line. If the long shaft wobbles, you can cut rubber hose a little longer than the gap, hold long-shaft aside as you work the hose onto the short-shaft to clear, align, and work the hose onto the long-shaft. Use soapy water as lubrication, it will dry.

If you really can't work the shafts aside, and the shaft rotation is less than 180 degrees, use fuel line and two small hose clamps. Slit the hose up the side so you can get it on. First(!) slip the clamps onto the shafts so you can clamp the hose.

 

[Sqeek]

Thanks dalehimself i see now

PRR suggestion sounds like a good one but i would use wire ties (plastic instead of hose clamps (metal) to secure the hose.

 

[Lojzek]

Couldn't a knob for a curled potentiometer shaft be used as a clutch, with a mod or two?

 

[huggygood]

6mm Arbre de potentiometre metal Coupleur EXTENDEUR COUPLEUR RALLONGE POT arbres | eBay

 

[levistubby]

From the pictures, the shafts seem to be slightly out of alignment. If they are, then a flexible coupling of some sort is needed rather than the otherwise ideal coupler linked to above.

 

[korpberget]

+1 on the fuel hose solution.

Dirt cheap, flexible and rigid enough.
KISS method.

 

[dalehimself]

The shafts aren't out of alignment, there was just nothing really supporting the front end where its supposed to be positioned in that picture. Thanks for the suggestions, I'll keep you posted on what I end up doing.