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True Or False

I wander if someone could answer this question for me , as slightly confused . Before anyone said’s any think haha its nothing to do with cross threading as I know how that is caused now . However the other day I was at the pub and my friend who is a apprentice mechanic , said to me that the bolt will sit flush if you were to force it in all the way but surely as it is at angle due to cross thread it will be at a slant and wont sit right . The only think I can think off is that your bending either the threads or the bolt it self to go in flush.

Wandered if you think it true or false

cross threading will make it go in crooked, sop no- it will not sit flush as designed. It will also make it not hold as tight.

So to clarify it will not sit flush is what your saying and sit wonky

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I think a cross-threaded bolt will sit flush; at least in most cases. A very short bolt might be visibly canted a bit.

Reminds me of the old Howdy Doody show with the WONDER bread commercials helps build strong bodies 8 ways. Then I wandered away from the TV set and went outside.

Bolt threads are long inclined planes with the bolt and the hole matched in the width and angle so that when they are put together they fit tightly and offer a strong resistance to pulling out. Cross threading means you are mashing the threads on either the bolt or the hole it goes into or both. So you are destroying the inclined planes and simply forcing the bolt in a hole. So the pull out resistance will always be less. Whether the head is crooked or not I think depends on the length of it and the size of the bolt. If it is a little off, just whack it with a mallet since the thing is destroyed anyway.

I thought Wonder bread built strong bodies 12 ways, guess they should have added ginkgo to the vitamins.

Context is important here. In some circumstances, a cross-threaded bolt will sit flush tightened all the way. In some circumstances it won’t. It depends on how long it is, how long the hole is, etc. A long bolt in a log hole will tend to straighten out because it has to align with the hole in order to be fully inserted. A short bolt in a short hole might make it through at an angle.

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In the old days it was 8 ways and then the improved version was 12 ways.

Frankly, I wandered off before finishing original post or some think.

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Right on @Whitey. The OP has wandered around cross threading in several posts. You can mess up threads by using mis matched threads or not having proper threads aligned. Bottom line is bolt and hole have to have the same thread and lined up properly

I wondered about that…


Who had more beers, you or your friends? Judging by the spelling you wrote this post while in the pub.


Shorter bolts if cross-threaded and fully seated, the head can indeed appear to be tilted with respect to the surface it fits against. That’s one way to tell they are cross threaded. The longer the bolt and hole, the less that effect will be. Say you have two old fashioned 5 foot diameter hand dug water wells, one is 10 feet deep and the other is 50 feet deep. If you put a long wood pole in the 10 foot well until it bottoms out and let it fall against the side, it will tilt at a larger angle w/respect to vertical than the same pole in the 50 foot well.

A long bolt can still sit flush because it had destroyed all the threads on the way in, if it hadn’t it would have just destroyed some of the threads and stopped advancing. Just in case you were wandering.