Hey What causes a thread to do this? And is it just the thread that is damaged or will the nuts thread be damaged too? TIA
Can be several reasons but in this case it's probably the locking device on the associated nut if that is the type used that you have pictured next to it. Some of the best locknuts aren't really meant to be used over and over but perhaps this one has and will distort the thread as you're undoing it.
And what if it was into something else threaded like a engine mount or caliper hanger? Is it always going to be the outside thread damaging the inside thread?
normally there would be a different kind of locking devise that doesn't grip the thread, other than a nylock nut. ie split washer
If that is a Nyloc nut in the pic, it looks to me as though a cut / split washer was used underneath it...........definitely a No, No. With Nyloc nuts only use a plain washer.
Although I am happy to be contradicted, the nut in the photograph looks very much like the type of locking nut that uses a slightly out of round ridge that is, as has already been mentioned, normally for a single use application on both the bolt and nut. I am now curious as to where this nut and bolt came from. Andy
don't think it's a nylock, see them often. yip they can damage the thread, you get another kind of nut thats criped at the top, they damage threads to.
have seen this quite a lot usually though it is caused by wrong thread ie pitch etc between nut and bolt ie metric bolt and an imperial nut goes on tight but not the right parts but could be caused by damaged thread picking up when tightened thus damaging the rest
Looking at it more closely, the nut looks a bit bashed on the top.........so is it one wot holds sprockets on?.....y'know, the ones with the slightly oval holes (forgotten what the type is called) and with a small flange............because they shouldn't have anything underneath them, not even a plain washer.
No, it braces the the rear caliper to stop it spinning when the brake is applied. There was no washers.
Cagiva use similar in some locations as std - fine for one use (as said) but chance of snagging on re-use/undoing.
Ah...One of them buggers......... Well, as Chris said, they will bugger a thread as easy as anything............change both bolt and nut if intending to use the same types. Several options instead of them, though.........here's a few....... Personally, I would use a castle nut, washer and split pin if there is room for them.......nothing like 'simple' really.
you can't really see but inside of nut is very similar. To be honest, it's so tight to do up it would never come undone on its own. I will probably chuck it back in unless I have something kicking round garage. So, in a nutshell, if a bolt goes like this it is due to the thread it is going into, rather than the end of the bolt being damaged.
Not nesser-celery....... A slightly badly cut lead in on the thread can bugger both male and female threads...........Try cutting a bolt down and getting it to go into a perfectly new nut for example.
It's a Fuji Lock Nut and the 2 steel teeth can not damage the top of the threads, they grip the root of the thread. They are designed for one application but the bolt can be re used.
It was putting the nut back on that damaged the threads. But getting it off/out was tough as so rusted on/in.
