How much exposed stud is safe?

[shadango]

No, this isnt a dirty question.   

When I got my car it had some copycat Weld rims.......and the stock studs on the drums.

The studs measured just under 1" of exposure to go thru the wheels.

The flange on the wheels is about 1/2".  That left just a hair less than a 1/2" for the lugnut to grab onto.

Well, left it as is and seemed ok....though I wondered if the length was inadequate. Figured I would deal with it when I did the disk brake swap.

Well, that time is now.

Bought a new 11.75" rotor and the studs measure 1', same as the drums....actually they are just a hair LONGEr than 1/"...maybe by a 1/32" or so.

Is 1/2" enough stud to grab onto or is this dangerous?  Should I swap out the studs? Dont really want to if its OK, but I also dont want to have an issue down the road....like I said, it was fine for a few thousamd miles that way.....

Thoughts?

[Supercuda]

Basic rule of thumb for wheel studs: Allow at least the diameter of the stud PAST the lug nut (acorn seat, open style), as installed on the vehicle. In other words, there should be twice the diameter of the stud past the wheel, for proper engagement. On shouldered styles, you want the stud to come out past the face of the wheel, but not so far as to prevent the lugnut from properly clamping the wheel. Since this style uses threads hidden inside the wheel for some of its clamping, the amount of stud past the wheel is not as critical. I would say that a safe amount of thread exposed, is more than 1/2", but not so much that it interferes with proper function of the parts, or tools used on those parts.

[FJ5_440]

If you are running the Weld wheel type rims with the thick cross section, I would run the extra long wheel studs also.  I had Weld wheels on my 64 Sport Fury, and the stock type lugs were NOT long enough to run safely.

[Kapteenikosmos]

Basic rule of thumb in machine design is that 5 intact threads is enough for steel applications. That is, you can turn the lugnut atleast 5 turns before it is completely tightened. When the application is as critical as this I think that I would keep mayby 8 threads as a minimum to keep on the safer side.

[cudazappa]

I was always taught that the stud should at least be flush with the face of an open lug nut.  (about 10 threads on a 1/2" stud). This will pass tech at most tracks.  Longer is preferred.

[Chryco Psycho]

engineering will tell you taht you need 1.5 x the width of the stud to be as strong to pull as shear so you need 3/4 of threads , if you are using a nut that trheads inside the wheel with a shoulder you are ok

[shadango]

The nuts I am using are chromed closed end nuts with the angled mating surface.  Not sure if that is what you call "shouldered" ??



I looked inside the lugnut and found that there is only 9/16" of thread inside the nut....so, while I am not going beyond the end of the stud inside the nut, I am at least using all of the threads......but I dont think any of the threads are extending beyond the inside threaded portion of the nut....but thaat would be the same and "flush with the end of an acorn nut", right?

[Changin Gears]

Sound OK if you're using all the threads in the nut.

[shadango]

I think I am, by my measuring.

...and they are 7/16" studs...........

[Chryco Psycho]

no those are not the shoulder nut I was Talking about but if you have 90% of the threads meshed you should be fine