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Post by matt1234 on Jul 9, 2017 13:01:04 GMT 1
What does cross threading actually mean like I know it when its misaligned but why does it cause the female and male threads to strip.
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remmington
Apprentice
Owns Spark Eroder
Posts: 4,966
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Post by remmington on Jul 9, 2017 14:41:28 GMT 1
Not sure how to embrace a response to this question without sounding like I am "taking the p*ss".
So with that in mind...
I will refrain from answering!
(How is that for restraint Noberator?)
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Post by chippie on Jul 9, 2017 15:08:44 GMT 1
Cross threading generally occurs when the axis' of the male and female parts are not aligned to one another....
Attempting to continue to make the join causes stress on the thread crests and eventually break off.....hence the stripped thread....generally caused by the ham-fisted brigade forcing the two parts together rather than finding the reason why they dont fit as they would normally....
How does that explain it?
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Post by matt1234 on Jul 9, 2017 16:35:34 GMT 1
So basically what your saying is , if you start to feel resistant on a turn on the thread and every turn afterwards is getting allot harder to turn it starting to cross thread and that what it doing the stress on the thread and if you start to feel resistant and the turns afterwards getting harder take it out and have a look.
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Post by chippie on Jul 9, 2017 16:46:09 GMT 1
I'm not sure where this thread is going.....( pun intended...)
It is not necessarily true that the bolt threads strip.....it may be the counterpart's threads that are damaged.....it depends on how well the thread was made/the material the parts are made from etc...any number of variables......
If parts that are mated together by male/female thread and are not fitting well, take them apart and find out why....there is usually a good reason and why cleanliness is a good thing....
This why we have thread chasers and die nuts....in our tool kits ( we do, dont we?)
I'm not being condescending but it isnt rocket science......
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Deleted
Deleted Member
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Post by Deleted on Jul 9, 2017 16:55:48 GMT 1
I'm not sure where this thread is going.....( pun intended...) It is not necessarily true that the bolt threads strip.....it may be the counterpart's threads that are damaged.....it depends on how well the thread was made/the material the parts are made from etc...any number of variables...... If parts that are mated together by male/female thread and are not fitting well, take them apart and find out why....there is usually a good reason and why cleanliness is a good thing.... This why we have thread chasers and die nuts....in our tool kits ( we do, dont we?) I'm not being condescending but it isnt rocket science...... It's nuts and bolts science  |
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Post by matt1234 on Jul 9, 2017 17:24:08 GMT 1
It just people keep saying to me you will know you have cross threaded a bolt as you can feel it . I have never felt it , is it obvious as for the reason why I am asking is because I'm just about to start a project on a bmw z4 and I've got strip the engine out e.c.t.
Like on some bolt they go in and have a slight resistant but then easy to turn again and then repeats this process again down the thread is this okay . Is that just muck on the thread .
I just need someone to explain to me that It will get stiffer if cross threaded and the sentence above me explained . I know it a stupid question but It my first proper strip out on a engine and this is one thing that is concerning me as I have never felt it before .
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Post by chippie on Jul 9, 2017 17:51:44 GMT 1
It just people keep saying to me you will know you have cross threaded a bolt as you can feel it . I have never felt it , is it obvious as for the reason why I am asking is because I'm just about to start a project on a bmw z4 and I've got strip the engine out e.c.t. Like on some bolt they go in and have a slight resistant but then easy to turn again and then repeats this process again down the thread is this okay . Is that just muck on the thread . I just need someone to explain to me that It will get stiffer if cross threaded and the sentence above me explained . I know it a stupid question but It my first proper strip out on a engine and this is one thing that is concerning me as I have never felt it before . Starting out on a Z4 is a bit ambitous...... Slight resistance is difficult to quantify in an abstract world like this.... If it was assembled before you took it apart, it must go back together........ I suggest you become acquainted with nuts and bolts of any description and have a feel for how they fit together........ thread engagement differs across a wide variety of thread forms and it comes down to experience and 'feel' when assembling parts...I speak from many years of engineering experience not just talk.... I might also add that using a torque wrench is important to ensure threads are not over tightened, which can also lead to premature thread failure... |
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Deleted
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Post by Deleted on Jul 9, 2017 19:56:36 GMT 1
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Post by Rhubarb on Jul 9, 2017 20:39:21 GMT 1
It just people keep saying to me you will know you have cross threaded a bolt as you can feel it . I have never felt it , is it obvious as for the reason why I am asking is because I'm just about to start a project on a bmw z4 and I've got strip the engine out e.c.t. Like on some bolt they go in and have a slight resistant but then easy to turn again and then repeats this process again down the thread is this okay . Is that just muck on the thread . I just need someone to explain to me that It will get stiffer if cross threaded and the sentence above me explained . I know it a stupid question but It my first proper strip out on a engine and this is one thing that is concerning me as I have never felt it before . Don't run before you can walk Otherwise it will end in tears |
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rpm
Apprentice
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Post by rpm on Jul 9, 2017 21:21:44 GMT 1
Firstly, doing a bolt up by hand, you will not cross thread it. Do it up until threads all way through the nut and then use tools.
Secondly, buy some metric standard bolts and some standard and fine thread nuts and then try and assemble them. You will see and understand the difference.
Sorry, but if you need more information than that, then what you are about to undertake is too much for you.
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Post by Joepublic on Jul 9, 2017 22:52:22 GMT 1
It just people keep saying to me you will know you have cross threaded a bolt as you can feel it . I have never felt it , is it obvious as for the reason why I am asking is because I'm just about to start a project on a bmw z4 and I've got strip the engine out e.c.t. Like on some bolt they go in and have a slight resistant but then easy to turn again and then repeats this process again down the thread is this okay . Is that just muck on the thread . I just need someone to explain to me that It will get stiffer if cross threaded and the sentence above me explained . I know it a stupid question but It my first proper strip out on a engine and this is one thing that is concerning me as I have never felt it before . Its putting a nut on a thread on a tilt so one side of the nut is further down the thread than the other, in practice when running the nut on with your fingers the nut will bind after half a turn or so, but if you used a long enough spanner you could destroy the thread on either / or the nut or bolt by using excessive force in conjunction with the leverage of the spanner |
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Post by Joepublic on Jul 9, 2017 22:55:42 GMT 1
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Post by Noberator on Jul 9, 2017 22:58:38 GMT 1
Not sure how to embrace a response to this question without sounding like I am "taking the p*ss". So with that in mind... I will refrain from answering! (How is that for restraint Noberator?)Fill ya boots Remmington if it makes you feel better. I'm ready,  |
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Post by chippie on Jul 10, 2017 12:07:46 GMT 1
I'd love to know what Remmington was gonna post....  This topic is driving me nuts.....  |
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