Replace magnetic connection point on spring reverb

[DrGonz78]

I have this 2-spring reverb in an old Kustom PA that had one of the springs just laying around broken off. Looking at a picture of sorts I understand that the little hook point that connects each side of the spring has a magnet piece and is soldered in place. I have a couple broken reverb units that have those little magnet parts that I could remove and put on this reverb. Might be a tough fix but it might work. Has anyone tried a repair like this before and had any luck?

[g1]

Yes. I've replaced those 'cores' before. It's tricky. If the sleeve the core goes into gets overheated you can melt the plastic it is housed in. Also there is some foam damping material around the core wire. It affects the tone.

[52 Bill]

I have this 2-spring reverb in an old Kustom PA that had one of the springs just laying around broken off. Looking at a picture of sorts I understand that the little hook point that connects each side of the spring has a magnet piece and is soldered in place. I have a couple broken reverb units that have those little magnet parts that I could remove and put on this reverb. Might be a tough fix but it might work. Has anyone tried a repair like this before and had any luck?

I've fixed tanks by replacing the entire transducer assembly with one from a different tank, and I have just replaced a broken end wire using a very thin guitar string with good results.

I have never had any luck in removing an original wire and reusing it on another tank. The wire will break at the soldered end. The plastic mounting bracket will melt when you apply heat to the spun brass inserts.

[g1]

I have just replaced a broken end wire using a very thin guitar string with good results.

Could you clarify the what and how of this?

[52 Bill]

Could you clarify the what and how of this?

A hundred years ago, when the only place you could buy replacement tanks was from OEM sources, if the small spring hook wire broke, you could look around the tank can and find the small ceramic magnet stuck to the inside of the can.

You could then pull out the end of the hook wire from the magnet and slide the magnet onto a thin plain guitar string, something like a .007 or .008. Then bend a hook into the string and fashion a replacement spring hook wire to replace the broken original one.

Later on, the magnets were epoxied onto the hook wires, so they were harder to remove them to reuse them.

Fender used to sell just the end assemblies for the tanks so that you could repair them by just drilling out one mounting screw. I think it used to cost $5 bucks for the replacement.

[g1]

Ok. So you still had the melting plastic issue I guess?
When I started (less than 100yrs ago ), those transducer assy.'s were up to $20 which is about the price of a tank now, but at that time the tanks were quite expensive, $50 or 60 if memory serves.

[52 Bill]

Ok. So you still had the melting plastic issue I guess?
When I started (less than 100yrs ago ), those transducer assy.'s were up to $20 which is about the price of a tank now, but at that time the tanks were quite expensive, $50 or 60 if memory serves.

Yes, that's the only reason why we would try and rebuild them. Now they are so cheap it hardly makes sense to fix them, unless you prefer the sound of the old tanks.

I found that you can file off the soldered end of the spring wire to keep from melting the plastic. Then you heatsink the tube with a pair of pliers while you quickly solder the replacement string.

[DrGonz78]

So I got it!! Bill gave me the idea that the plastic melts so I pulled out the long ferrule tube off the unit I was repairing.


I then broke off the same piece from the donor unit, which included the ferrite magnet attached.



Then I managed to get donor parts back into the repaired unit. They fit very snug and I can always dab a bit of super glue onto it, although I don't think these will fall out on their own.



Thanks again for the help and your experiences with these things Bill and G1!! Sometimes you repair something just to see if it is even possible.

[drewl]

I've even used bus wire, or just left over resistor/capacitor leads pushed through and bent into a loop.
They hold.