Why do people put a ball bearing under a stud??

I noticed that someone put one steel ball per hole (ball bearing) in the stud hole before the stud was installed on my quick change cover studs. what is the reason for this. Is it just to give me more exposed threads?? or so the stud does not bottom out?? or is there better reason??

 

Reasons I can think of:
1-the studs they had on hand weren't long enough, so they dropped a ball in there.
2- they were too cheap to buy/find the correct length studs
3 - they wanted to brag about the extra ball bearings in the casting?

my .02

 

maybe to pass the 'ball bearing test?'
I think it is just to seat the stud against steel.

 

It takes balls to cut corners like that.

 

Good way to crack the casting, if your into that sort of thing...

 

To be 'just a stud' is merely 'to be'.

To be a 'Ball'n'stud', well...that's goin' some.....

 

I'd imagine the stud itself can be fully torqued without exerting case splitting force into the bottom of the holes that can't be fully taped. Id also imagine that if you needed the stud out , it would come right out because the end of it wasn't distorted.

That or someone cut corners, could afford a quick change but not the studs.

 

I thought about this and just wondered if it worked by tightening the thread of the stud against the thread of the the casting so when you undo the nut the stud does not come out.

cheers vin

 

I am sure this was done to prevent the threads on the ends of the studs from being messed up when the stud was bottomed out in the tapped hole. I have seen many parts destroyed because the stud was driven into the imperfect threads in the tapped hole and when the stud was backed out the messed up threads on the stud ruined the threads in the part. Another way to prevent it is to turn a dog point on the end of the stud.

 

When you were able to get steel studs out of the aluminum casting your question was answered.

 

Bottoming the stud in the hole is another good way to crack a casting.

 

I have been known to do that when one gets around the Ol' Lady. Then while he is down I give him a good solid kick in the teeth.

Ball bearings never leave home without one.

I am kind of hangin' with 31 Vicky on this one his explainantion sounds logiocal to me.

 

It's a positive stop for the stud

Alum housing expands with heat

This method keeps the stud tight when changing gears on a hot housing between races

Those ball bearings are put in at the factory and are included when you buy a replacement stud set from all the manufactures

Tony

 

boom!^

 

The collective power of the Hamb is awesome! Thanks guys!

 

I wonder if the ball-bearing causes a slight spreading of the end of the stud, out into the threads in the casting, reducing the risk of loosening? Just a thought.

 

Someone told me that the technical name for that is "Studs Terkel". I had to look it up to be sure though.

 

See I wasn`t wasting time on the HAMB...I was learning stuff! Thanks Tony!

 

a any oil or grease left in the hole will cause the case to crack when it gets tightened the bearing leaves an air pocket at the bottom

 

Yup. This ball-bearing business makes me real uneasy. I just dont like the idea of ANYTHING pressing on the bottom of a blind hole with a stud on top of it...

 

There is no oil or grease in these holes when assembling them new

The studs are ment to stay put....
Sometimes we have that cover off 4 or 5 times a night

They have been in every quickchange I have bought in over 25 years of round track racing

And the ones that where built when I was to young and just hanging on the fence watching

And I've never had a stud or housing failure

And if you ever had to remove a wore out or broken stud in an old halibrand from the 60's you'd be glad the newer ones have them
Especially if you have a magnesium rear

Tony

 

Obviously, they didn't think the engine had enough balls as it was.........

 

And to lesson the worrying naysayers

All race aluminum engine blocks have a" bullet nose "on the end of all head and main studs, so the stud can stop at the bottom of the hole and be snug, not wedge against the shoulder of the stud

Tony

 

They shouldn't wedge against the shoulder of the stud either. Finger tight is the rule where I come from. I will admit though, I have never worked on a quickchange. Maybe I am being overly paranoid. But its the way I was taught, been doing it that way for 35 yrs, ect ect.

 

"Its all ball bearings nowadays."

 

Are the threads all run with a bottoming tap or not? i would think the ball bearing would allow the studs to seat at the same distance and never have a chance to gaul the case upon removal. I would think they get Loctite coated before being installed.

 

Ding Ding Ding - We have a winner!

new studs from ARP often have a ball end on them to keep them from threading down into a part of the hole that wasn't fully threaded. You do not torque studs in place, anyway. They go in finger tight, then you torque the nut after installing the cover, head, manifold, whatever.

 

good one LOL ! !!

 

For my aluminum quickchange or any aluminum application I tend to agree with goatroper02. If the stud bottomed out and was tightened would'nt the case crack as opposed to damaging/distorting the stud since aluminum is softer?

I checked Hot Rod Works stud kits for quickies, they also have ball bearings included.

 

I guess guys just dont have the skills anymore. I have bottom-tapped every blind hole in every motor I have built since I was 16. Never even thought of it as a big thing, its just part of basic block prep, along with grinding any flash off, chamfering the tops of bolt holes, knocking the hard edge off the tops of the bores, ect. In this day of crate motors, no one knows how to build motors anymore.