Fixing Auto Return on my JVC AL-A1

[greenhorn]

I was lucky to find out that the Reason for my TT's auto return not working was a piece that had broken off from the base of the arm, and it was still inside. A little M seal later...



The innards

There isn't much to it. It's Almost entirely plastic. I have no idea what that spring is there for. The only thing nearby is the broken piece of plastic itself - Not sure why they have a spring between two parts of the arm base which are fixed together, and it can't be attatched to something else, as that would restrict the movement of the arm.

Waiting for it to set. Hopefully I should have a fully functioning TT by tomorrow! Now if only I could find one more of its missing feet!

 

[Saket]

Hey Greenhorn,

I think using Araldite in place of mseal would be much better. Don't think that mseal would be as strong & durable as a joint put together by araldite.

Regards.

 

[greenhorn]

The cross section area of the broken piece was very small. I've had less than satisfactory results using araldite in such places, especially where a lot of sheer stress is involved.

Even my dad had recommended araldite, but after my experience with fixing a broken leaf spring, I decided to go with M seal

 

[omishra]

It seems you need strength and not visual appearance at joint. Clean it and make both part together as they would be look after joint made. Now take couple of metal strips from toys etc, bend it over at least three sides. Imagin a metal octopus sitting over the hole where tonearm wires are coming out. It's holding those broken pieces together and letting wire and other movements freely. Now pierce these metal strips into both plastics with hot soldering rod.

For better suggestion please post multiple side close up pics. That 3M tape is confusing me to imagin original part. Remove it. I can draw diagram for this. No glue will help you here.

 

[Saket]

I have been in such a situation where the adjoining areas of the plate to be stuck was very small hence, araldite alone was not a solution. What I did is that first I stuck the plates like that only. Then put two metal strips on both sides for reinforcing that stuck area. It has been 3-4 years now since this experiment; and mind it, this mechanism bears the stress of the idler, hence takes some significant load on my HMV record player. You may try this idea too.

 

[greenhorn]

the 3M and the white plastic block (it's the cap off a VGA connector) are just there to hold it in place while it set. It seems to be working fine. Will take detailed shots when I open it up to fill it up with modeling clay - that't the next plan

Regarding the metal - this joint flexes a lot. I needed some metal which would flex a bit, but retain its original shape. I dismantled a toy car, but the spring inside it was too flexible, and the metal strips I could find were too stiff.

This is a question that I still haven't found a suitable material for. even in my cassette deck, after sticking the part back, the mechanism has become more stiff, since less of the metal/plastic is bending.