Helicoil! Who knew?!

[LWJ]

After finding the incorrect torque on an M5 bolt in an aluminum casting and totally making a mess of things, I did some research and bought a helicoil kit.

Easy. Seems legit. Fast install. I didn’t even pull the casting off my motorcycle and used a hand drill.

Felt like cheating.

And it worked.

I have always heard about helicoils and know the argument for nutserts as well as rivnuts.

But wow! This was a great fix.

[dewolf]

They are brilliant. Broke two water pump bolts on a 928. Drilled them out, tapped them using the Helicoil kit and screwed the insert in. Easy.

[speeder]

I have some stripped-out bolt holes in my MGB passenger door for the latch. I was thinking about helicoils but wondered if they are strong enough?

[LWJ]

Supposed to be stronger than original. Just not a good application if you removed the bolt often.

[908/930]

Given a choice I prefer a key locking thread insert, better for items that will have the bolt removed frequently, but Heli-coils work well.

[speeder]

Definitely will not have the fasteners removed often if ever. It’s a door latch.

[Seabear]

Helicoils are common in aerospace applications. Used in aluminum and magnesium castings to enable a stronger more durable thread.

[herr_oberst]

Originally Posted by speeder

Definitely will not have the fasteners removed often if ever. It’s a door latch.

Hopefully the door latch is aligned right now and you can install the 'coils one at a time, because I'm still fussing with one of the doors on my BMW and I've loosened those screws at least a dozen times and I'm still not happy. Maybe a couple of dozen.
I doubt a helicoil will be able to withstand that.

Is there a way to take the latch apart and weld nuts to the back?

[speeder]

Originally Posted by herr_oberst

Hopefully the door latch is aligned right now and you can install the 'coils one at a time, because I'm still fussing with one of the doors on my BMW and I've loosened those screws at least a dozen times and I'm still not happy. Maybe a couple of dozen.
I doubt a helicoil will be able to withstand that.

Is there a way to take the latch apart and weld nuts to the back?

The nuts would have to be welded into the inside of the door. Not impossible but not easy either.

[dw1]

Originally Posted by Seabear

Helicoils are common in aerospace applications. Used in aluminum and magnesium castings to enable a stronger more durable thread.

And in medical production equipment applications where plastic (Delrin) and anodized aluminum (esp. 2024-T4 & -T351) are common. They are especially useful with smaller thread sizes in relatively soft materials. They are also used in strong but brittle plastics, like high % filled polycarbonate.

Not to mention a real life saver when threads cannot be re-tapped to the previous size because the bolt had to be drilled out and it couldn't be done all that precisely.

PEM inserts (our generic name for press-in threaded inserts) certainly have their place, especially for sheet metal, but our tooling fabrication & repair machine shop was always well stocked with various Helicoil sizes.

[herr_oberst]

Originally Posted by speeder

The nuts would have to be welded into the inside of the door. Not impossible but not easy either.

How about a 'floating' plate?

[island911]

Denis, it sounds like you would want to use rivnuts.

Rivnuts are essentially like expanding wall anchors for sheet metal.

[pete3799]

Originally Posted by island911

Denis, it sounds like you would want to use rivnuts.

Rivnuts are essentially like expanding wall anchors for sheet metal.

This.

[911boost]

My Westy has one for a spark plug that got stripped, it’s held up great.

[smadsen]

Heli coils work so much better than JB Weld.

[Scott Douglas]

Denis - Look into floating nut plates if you need to maintain 'adjust ability' in the nut location.

Heli coils are great as long as you have the needed parent material to complete the installation correctly.

[GH85Carrera]

On my 911 the first time I removed the AC compressor I noticed one of the rear mounting bolts was not tight. When I get it off and looked, it was obvious it was stripped. I could cuss the previous owner's mechanic back then. I went down to Fastenall and brought the bolt and photo of the mount. They set me up with the Helicoil kit. The right tap and the coil, and it went in just fine.

I read the manual and found the proper torque setting for the compressor bolts, and made sure to torque them to spec. 27 years later, the compressor has had to come off many time for valve adjustments or spark plug replacements. It has held up just fine.

[gordner]

Originally Posted by speeder

I have some stripped-out bolt holes in my MGB passenger door for the latch. I was thinking about helicoils but wondered if they are strong enough?

We are allowed to use them in many applications on aircraft, including structural. That would not be the case were they not the equal of the original.

[T77911S]

i have used them with good results.

i have also dealt with one or two that were NOT being friendly at all.
i would still use them.
i seem to remember having one screw out on me with the bolt.

[kolo]

look at timeserts also