CK5
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dana 60 3/4" studs
- Thread starter 53chevy
- Start date
Vombrown
Mountain Man
Should be fine. Is it drilled deeper or is that just as far as it will go in?
The general rule of thumb I'm aware of is that a fastener needs to be threaded in, at a minimum, the diameter of the fastener....IE, 3/4" diameter bolt needs to be threaded in 3/4". Beyond that you aren't gaining any strength. If anything those that seem to thread in more than that rule of thumb (head bolts, exhaust manifold bolts, etc), it's probably based on ease of assembly, not strength, since none of the nut/bolt assemblies use ridiculously thick nuts, even the axle u-bolts.
May veer off topic, but it seems applicable for this post, if anyone has anything to add to that (or refute).
May veer off topic, but it seems applicable for this post, if anyone has anything to add to that (or refute).
Doesn't exactly answer your question, but wanted to mention the extra thick nuts.
I own a book called Engineering Reminiscences by Charles Porter.
I actually have two copies. One is an original signed by the author in 1908. The other is a copy.
Got the copy here:
https://www.amazon.com/Engineering-...929&sr=8-1&keywords=engineering+reminiscences
This guy died in his 90s, and lived through most of the industrial revolution. He met people like Professor Rankin, Mr Pratt and Mr. Whitney, and was involved with some of the greatest achievements ever.
Many of the things we take for granted, he was around when they were created.
For instance, he was visiting a small machine shop, and saw them drilling holes in steel with some kind of new tool. Up until then, everybody he knew drilled holes with boring bars.
These were some kind of twisted rod. They said that they heated flat bars, twisted them, then sharpened the ends. Called them "twist drills".
He also met the guy who started Western Union telegraph. Turned out he was the sheriff from his home town.
I don't have the book in front of me, but there was somebody of that time that was The authority on all things machinery wise. When you needed to know how to do something, you read his writing on the subject, since he was the best there was.
Porter was in England I think, at a engineering show. They were huge back then, think the electronics show in Vegas now.
He was walking by a display, and there was a large bolt clamped in an apparatus that had been pulled completely in two. The head end was clamped in the base, and the drawbar that pulled it to failure was held to the bolt with a nut that was not any more than the thickness of the bolt its self.
Porter was shocked, and exclaimed " Old -------Lied!"
The expert had proclaimed that to harness the full strength of a bolt, the nut had to be a certain number of times thicker than the diameter of the bolt. Of course, he had no proof of that claim, it just sounded right to him, so he stated it as fact and everybody the whole world over accepted it.
These guys with their hydraulic pulling machine had proven him wrong since the nut was nowhere near as thick as he said it had to be, and the bolt had pulled in two rather than the nut or threads failing.
Since I read that, I have seen many old time boilers, and other machines that had ridiculously thick nuts. Now I know why. There are other reasons, but for anything built in the 1800s or for a while in the 1900s, it was because of that one guy and his idea of the way things should be.
I own a book called Engineering Reminiscences by Charles Porter.
I actually have two copies. One is an original signed by the author in 1908. The other is a copy.
Got the copy here:
https://www.amazon.com/Engineering-...929&sr=8-1&keywords=engineering+reminiscences
This guy died in his 90s, and lived through most of the industrial revolution. He met people like Professor Rankin, Mr Pratt and Mr. Whitney, and was involved with some of the greatest achievements ever.
Many of the things we take for granted, he was around when they were created.
For instance, he was visiting a small machine shop, and saw them drilling holes in steel with some kind of new tool. Up until then, everybody he knew drilled holes with boring bars.
These were some kind of twisted rod. They said that they heated flat bars, twisted them, then sharpened the ends. Called them "twist drills".
He also met the guy who started Western Union telegraph. Turned out he was the sheriff from his home town.
I don't have the book in front of me, but there was somebody of that time that was The authority on all things machinery wise. When you needed to know how to do something, you read his writing on the subject, since he was the best there was.
Porter was in England I think, at a engineering show. They were huge back then, think the electronics show in Vegas now.
He was walking by a display, and there was a large bolt clamped in an apparatus that had been pulled completely in two. The head end was clamped in the base, and the drawbar that pulled it to failure was held to the bolt with a nut that was not any more than the thickness of the bolt its self.
Porter was shocked, and exclaimed " Old -------Lied!"
The expert had proclaimed that to harness the full strength of a bolt, the nut had to be a certain number of times thicker than the diameter of the bolt. Of course, he had no proof of that claim, it just sounded right to him, so he stated it as fact and everybody the whole world over accepted it.
These guys with their hydraulic pulling machine had proven him wrong since the nut was nowhere near as thick as he said it had to be, and the bolt had pulled in two rather than the nut or threads failing.
Since I read that, I have seen many old time boilers, and other machines that had ridiculously thick nuts. Now I know why. There are other reasons, but for anything built in the 1800s or for a while in the 1900s, it was because of that one guy and his idea of the way things should be.
Not trying to argue, I suspect much of what is out there is just to make sure people err on the side of caution. 1.5 times would be hard to get wrong.
This site (can't figure out who authored it) https://engineerdog.com/2015/01/11/10-tricks-engineers-need-to-know-about-fasteners/ says the magic number is 6 engaged threads:
#6. If you’ve ever designed a part with a threaded hole, you may have wondered:‘How many threads do I need to make a strong connection?’ The answer is that it varies, but six at most.
Bolts actually stretch very slightly when force is applied, which causes the loading on each thread to be different. Because of this stretch, when you apply a tensile load on a threaded fastener the first thread at the point of connection sees the highest percentage of the load. The load on each successive thread decreases from there, as seen in the table below.
Additional threads beyond the sixth will not further distribute the load and will not make the connection any stronger.
So will a bolt break before the nut strips? Yes! Nuts typically have no less than three internal threads, but nut thickness standards have been selected on the basis that the bolt will always sustain tensile fracture before the nut will strip."
Given that even in today's day and age split lock washers are still "results may vary", the truth is probably somewhere in between everything we've heard, been told, and taught.
That is what I have learned and if that number had a safety margin built in I am fine with that.
In commercial vehicle inspection and race cars they say lug nts should leave 3 threads showing to be safe.
Is that true?
I don't think so but it some safety procedure someone decided to make sure there is no confusion about the nut fully threaded.
I definitely would have no less than the thickness but when possible I would try 1.5x
I think the 3 threads showing is for a quick glance that full nut engagement is assured.
Dorian, your facts prove true as well.... if you consider that a 3/4" diameter bolt has 10TPI (coarse threads) it will have 7.5 threads engaged to equal its diameter. A 3/4 typical nut is slightly more than .625 height, so that would only leave 6.25 threads of engagement.
Dorian, your facts prove true as well.... if you consider that a 3/4" diameter bolt has 10TPI (coarse threads) it will have 7.5 threads engaged to equal its diameter. A 3/4 typical nut is slightly more than .625 height, so that would only leave 6.25 threads of engagement.
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I drilled mine for 3/4" studs, they are in deeper than an inch. Error on the side of caution, remember the housing is cast and it doesn't hold threads as well as we would like. Mine are around an inch and a half deep, I think.
I helped fix that, I think that was the last trip I saw his Blazer take.
Where are you finding 3/4" studs for this application that aren't allthread?
Where are you finding 3/4" studs for this application that aren't allthread?
I'm using grade 8 allthread in mine. Guess I shouldn't say "studs". Still have a foot or so left in the garage. lol
The numbers I heard were 1X for steel, and 1.5X for aluminum. Then again for aluminum I think if it's really important steel inserts are even better.
Where did you find grade 8 allthread?
An old oil field supply/hardware store by my house. I REALLY miss them, Tad (the owner) always had what I needed no matter how off the wall it was.
