loctite thread a hole

[debtman7]

Ok I can finally report on this stuff. Last time I tried to use it to fix one of the slide cover holes on my carb that was cross threaded, I ended up trying to put the wrong screw in it and messed it all up so I just threaded it for a new screw.

Well I got a chance to try it again on this POS 50 cc scooter my dad bought. I, again, stripped the threads on the carb that bolts it to the intake manifold. DOH. Well I figured I could at least try the loctite stuff again (it has enough to do probably 6 or more small screw/bolt holes)

This is basically a two part epoxy, but also includes a special loctite thread release compound you paint on your bolt. You mix up the two epoxy parts, paint your bolt with the release agent, then fill the hole up with the epoxy. Wait five minutes, unscrew the bolt, let it cure for several hours. Done!

My first attempt failed. The hole I was trying to fix went all the way through so as instructed I covered the bottom with tape and filled the hole up. Then I screwed in the bolt. Unfortunately, I didn't screw it all the way through and ended up with a solid 2-3mm layer of epxoy at the bottom of the hole. Oops. This did, however, give me the chance to discover that this stuff is HARD. I had to drill it out and then use a thread tap to clean the remainder out. I got the hole pretty clean again, however at this point it had essentially no threading left at all.

Take two. This time I made sure to get the bolt all the way through, which of course leaked some out the bottom. Clean that up right away, since as I found once it dries it's a Buddha Loves You to get off. I removed the bolt after 5 minutes (don't wait longer, even at 5 minutes it's tough to get out and I had to carefully use a wrench). To be safe I let it cure up overnight.

The final result was great, I put the carb back on and bolted it down and bam, nice and snug. You could look in the hole and see nice perfectly formed threads. I wouldn't trust this on a critical part or anything that requires a lot of torque, but for less critical applications, or old crappy scooters, definately worth a shot. They claim it can handle something like 150 ft-lbs of torque once cured.

[Egaeus]

You forgot the important part:

What did you use?

[debtman7]

You forgot the important part:

What did you use?

For what?

[Egaeus]

to make the thread.  The epoxy stuff.

[debtman7]

to make the thread.  The epoxy stuff.

title of the post... loctite thread a hole. NAPA was the only place I could find it at.

Ok just looked up the actual name, it's Loctite Form-A-Thread although they seem to be mostly labeled Permatex Stripped Thread Repair Kit.

http://www.acehardware.com/product/index.jsp?productId=1295869&cp=1255100.1258962

[ohgood]

Is using the bolt to form threads in the part just to negate needing a tap ?

I could see using two part epoxy to repair a light duty tapped hole. Why not just use a tap after the epoxy sets proper ?

Now I have to get some of it and try out it's claimed torque resistance ! There was 'Pig Putty' a while back that did a good job. I don't remember what it's holding strength was though.

Good report on what looks to be a good product. 

[debtman7]

Yeah, the idea is no need to tap and it forms perfectly to the bolt. You could just tap epoxy, I guess, the advantage here is that you can use any size bolt/hole without having to buy a complete tapping set or keep buying individually sized taps.

[Jay_wolf]

not sure they sell it over this side of the pond,

[sledge]

Jay?
Plenty of similar products available over here. Check out www.belzona.co.uk,
Specificaly the 1000 series metalic polymer

[Jay_wolf]

sounds gd , i hacksawed the bolt off,. now i have 2 drill out the hole ., so this seems perfect thanks 

[debtman7]

sounds gd , i hacksawed the bolt off,. now i have 2 drill out the hole ., so this seems perfect thanks 

Er, no... I would not use that on fork clamp bolts. It may do ok, for a while, but those things are pretty important, something you wouldn't want to fail. I wouldn't ride around with a critical part fixed on with that stuff. Epoxy may or may not do ok there, but I wouldn't chance it.

[Egaeus]

sounds gd , i hacksawed the bolt off,. now i have 2 drill out the hole ., so this seems perfect thanks 

Er, no... I would not use that on fork clamp bolts. It may do ok, for a while, but those things are pretty important, something you wouldn't want to fail. I wouldn't ride around with a critical part fixed on with that stuff. Epoxy may or may not do ok there, but I wouldn't chance it.

I do indeed wholeheartedly concur.  Go to a machine shop before you kill yourself. 

The bad news is that you've probably doubled or tripled the cost of removing the bolt by hacksawing the head off.  The good news is...well, there's not really any good news. 

[sledge]

I will back those statements up, those rmetal-epair compounds are good if used and applied correctly but I wouldnt trust them on something safety related and they can be expensive to buy. Look in the yellow pages for "machinists" and make a few phone calls.

[ohgood]

I will back those statements up, those rmetal-epair compounds are good if used and applied correctly but I wouldnt trust them on something safety related and they can be expensive to buy. Look in the yellow pages for "machinists" and make a few phone calls.

You rang sir ?

[ohgood]

Bellzona is kick ass stuff too. We use it on 30,000 lb. prop shafts (cosmetic only) but if it can stand up to the torque/vibration/heat/salt water, 24/7 operation for 5-10 years on a TUGBOAT, it'll prolly hold up to minor things on a motorbike.

[sledge]

Belzona, when its good its good, when its bad its very bad. and a lot of our clients will not accept its use in mechanical reclaimation work under any circumstance. I have mixed opinions, Its pulled us out of the s**t a few times but I have also seen it fail with expensive and often "spectacular" results. I wouldnt be 100% comfortable knowing my forks were held together with the stuff but others might be. A helicoil followed by a pull-test and a go/no-go plug-gauge test is the way to go.