Thread repair options

[Pugglt Auld Jock]

At college, back in the '60's, I was taught various strategies for reclaiming and/or repairing a damaged/stripped out screw thread. One of the most common is the Helicoil system which we were actually taught to use and for years that has been my standard "go to" when faced with a thread which is beyond a simple clean up with a tap. Then, a number of years ago I became aware of "Time serts" and, although they require quite a bit more work than doing a Helicoil, I've become a bit obsessed with giving them a try.

Now I'm going to have to address a damaged thread in one of the caliper pins on the Ibiza I thought "Great, just the excuse I was needing". Then I came across this video:



Now I'm not so sure. I still like the idea of the Time sert but now I don't think it's worth the extra expense and bother of doing it. Think I'll just stick with what I know and Helicoil it.

I quite like the idea of these too:

https://www.ebay.co.uk/p/1601701613...lBQXd0dj8mk5bubNXObzh2bc1ArXEr-8aAvxhEALw_wcB

I think they would be especially useful where a real "Horlicks of a mess" had been made of the thread to such an extent that a helicoil would be impractical. This second system is quite limited in application, You couldn't use it in a blind hole for instance, but for it's specific purpose it looks good with not too much "precision" required in tool use to be effective. I like also that it gives you that separate M9 tap just in case the original threads will clean up.

Anyone who would like to expand my knowledge base by commenting would be very welcome
Regards
Jock

 

[Pugglt Auld Jock]

I like also that it gives you that separate M9 tap just in case the original threads will clean up.

Just been reading a review on one of the seller's sites for this product and it got a 100% recommendation. Interestingly just one customer stated that the insert had compressed slightly when installed which made the slider pin tight to wind in. However rather than risk jamming/damaging the pin he ran the included M9 tap through the insert which cleaned it up to the correct diameter.

Maybe that tap is not part of the kit so you can try cleaning up the original thread "just in case" it can be made serviceable again, but so that you can open out the thread in the insert if it crushes up slightly as it's being installed?

 

[portland_bill]

Interesting topic, but that video gets irritating before it finishes, so dropped out around half-way through.

After a little thought, there's a flaw in his testing. He is testing to the yield strength of the bolt, but surely he should be testing to the expected limits for the base material. As I understand it, helicoils were originally created to make threads in softer materials, like aluminium, stronger. Thread inserts are sometimes used in aluminium as an original fitment, before any repair is necessary, as the insert makes a stronger thread.

Some time ago I saw a listing of the various thread insert types, with their advantages/disadvantages, and their intended uses. Sadly cannot find this now.
Needs more research, perhaps from manufacturer's websites to fully understand the various differences.