Repairing internal thread – Chin Spoiler Alfa Romeo 90
The internal thread cut into the inner side of the chin spoiler on my Alfa 90 was ripped out on one side after an encounter at speed with a large feral cat.
As the thread appears to have been originally cut into a resin boss built into the fibreglass spoiler, I puzzled over a possible fix for it. Originally, I thought of cutting a larger hole in the boss and then setting a 14mm nut into it with resin or j-weld or similar. Had to discard that idea as it would have meant having to weaken the walls of the boss in order to make space for the nut.
My local plastic welder came up with a better concept – to drill out the boss and create a new internal thread using a 2 pack resin filler.
I decided to give his idea a try. Attached is my little "how to".
Hope he came off much, much worse than your spoiler. As they say, there is only one good sort of cat.... particularly native animal killing varmints! ;D