Pretty sure that this can't be salvaged but i figured it wouldn't hurt to ask you all. As you can see from the pictures, the plastic corroded on the inside of the knob. The other seven knobs work perfectly for the time being. I've gone ahead and ordered new replacement knobs from stewmac but just wanted to see if anybody knows of any miracle cure to reharden the rotten innards of this knob so that it could be reinstalled.
Super glue + get new tuners and keep those forever somewhere else!
Sorry guys...should have mentioned that I had already tried super glue to no avail. I had cleaned the plastic residue off of the metal post and filled the knob with a few drops of super glue and stuck it back on. I let it sit overnight and was disappointed the next day to find that the knob just spun on the metal post instead of grabbing it.
I've had good luck with Gorilla glue when I need to join metal and plastic. It expands, so it needs a way to escape.
I would then be using 'Weldbond' meta epoxy.
If it is something you won't be able to see, I would use an epoxy, like JB Weld or similar. It is thick and dries hard like hard plastic.
Hi John- There is a two part epoxy that Lowes sels that will bond metal to plastic or just about any material--
give it a try, and I think it might work for you --- peace, Donald
Will give epoxy a try. Thanks for the advice everyone. Will let you know how it turns out.
I might try filling the hole completely with epoxy or whatever, and then re-drilling the hole.
I have not tried it yet, but there is a method described in the GAM journal No. 108 that just came out. It described how to replace the knob. Use a small piece of wood, drill a hole of diameter that matches the knob to a depth that matches that of the knobs thickness. From one side, drill another smaller hole into the cavity created by the first hole. This smaller hole is used to insert the metal tuner post into. Use a hard setting epoxy with appropriate color added to fill the larger hole and bond to the inserted post. Once cured that epoxy can be shaped as needed.
Looks like epoxy did the trick. My local hardware store didn't carry any of the brands you all had recommended, but the owner of the store steered me toward Devcon "plastic welder" epoxy. Worked like a charm. Thanks again to everybody for the advice.