Redrilling wheels - has this guy found the limit?

I am commenting on increased speed due to not having to make sure that the wheel nuts are tightened in stages firstly finger tight then more torque to make sure centring occurs. Not the fact for speed of lining up bolts with holes or not as the case is with studs.

None of this makes a difference to whether the original wheels can be used or not as spigot rings can be made to suit. The subject seems to be avoided.

 

Note Point A in picture, a good ~10mm depth for bolt clamping.

 

The wheel coming off isn't the fault of the spigot. The bolts became loose, and the clamping force was lost. In this case a spigot would have helped support the wheel when the bolts came loose, but it wouldn't have stopped the intial cause of the failure of the joint.

You had obviously managed to centre the wheel ok, or you would have noticed vibrations in the 5 laps you did manage. I suspect that the bolts would have turned upon a re-torque after a lap or so, much the same as you're recommended to recheck the bolts on a road car after fitting a wheel after a number of miles.

 

All those that say 'nay' to spigots, front up your evidence.

Saying 'my wheels haven't fallen off my road car, therefore it's all fine' doesn't address the track failures seen, and merely suggests that it requires a little more in the way of tough conditions.

 

Wheel bolts and most bolted joints are not designed for the bolt to the take shear loads. The shear loads should be accomodated by the friction force between the two clamped (bolted) components or other means such as doweling.

But If we are going to say spigots are used to stop shear forces on the bolts then we should also be saying that on driven and braked wheels that we should use dowels to stop the shear forces being put upon the bolts when drive or braking force is applied to the wheel via the hub or vise versa. We do not see these put into most wheel fixing applications so therefore the clamping force must be strong enough to stop these shear loads being transferred to the bolts. Thus we do not need spigots to stop the wheel from moving on it's hub. Correctly used and machined taper bolts or nuts and corrsepnding seats in the wheels will ensure the centring of the wheel.

But we do need to ensure correct torquing to make sure the clamping fore and resultant friction stopping any shear force in the bolts is high enough.

 

A few years back, I bought a set of alloys from ebay, fitted R888s on them, and tried them out on my 2.0 16v Mk2 golf. Foolishly, I hadn't checked the spigot size - they're 60.1 Renault fit. The bolts were properly torqued up.

Under hard acceleration, you could feel the wheels moving around (it was a bit like axle tramp - felt like the wheels weren't round).

I bought and fitted Spigot rings and the issue went away. I think the wheel was moving around on the face of the hub, and if I'd gone on track like that I'd have ended up losing a wheel.

If you want to run without spigot rings, that's up to you. Write some goodbye notes to your loved ones first.

 

What stops them from moving around under braking and acceleration etc now? If the clamping force from the bolts didn't stop it then what stops it with the addition of spigot rings?

 

Is the length of unsupported stud not an issue when there are no spigots supporting the wheel?
Surely the longer the unsupported studs are, the more leverage the wheel will have acting on the studs in shear, to start moving around initially and then loosening off as this movement increases.

My T25 van has steel wheels and no spigots supporting or centring the wheel as standard, however the wheel studs will be lucky if there is 3mm of length between the threads in the flange and the taper of the stud in the conical seat of the steel wheel rim.

I am in the spigot ring gang personally, The theory is all very well, but why take the chance. If you have spacers on you are probably running with the incorrect ET anyway.

 

Spigots or size on size fitting prevent the wheel from moving up and down on the bolts/tapers. It stands to fact that if there's a gap in the bore, the forces working on the wheel will eventually either move the wheel off centre, or start to elongated/damage either the bolt hole or surrounding countersink that the bolt sits on. Thats why when you buy wheels, you buy them either to fit, or with the recommended spigot rings in place.
Even with the bolts torqued up(which isn't a huge amount when you look it up) it isn't going to enough to stop the weight of the car plus it's dynamic forces when moving to hold the wheel true without something evetually giving.
I'm not sure how many companies supply their cars with wheels that don't have a sliding fit onto the hub, or how many supply them with a gap for it to all jiggle about? I'm sure it's zero.
From experience, and with proper wheel bolt tightening, I've had a wheel near-as-damit fall off on the motorway for lack of spigots.
If you've used them without and been ok then you've probably been lucky.

On a 2nd note, I used to argue the same point about not needing them, then I found out 1st hand you do.

 

My assumption is the clamping force of the bolts should stop the shear movement from getting to the studs. But then with spacers you are increasing the length of stud which is being torqued so maybe the same torque setting on the torque wrench is not giving the same clamping force as before. (this is not proven just my thinking out loud, correct me if i'm wrong.) Im going to go hide in my box and do some thinking.

Spigots do add an element of fail-safe to the system if for some reason the bolts are loose and make movement.

 

http://www.eng-tips.com/viewthread.cfm?qid=152939&page=1

 

For the cost of a set of spigots, why not run them for `piece of mind` rather than perpetuate an argument on who`s engineering knowledge is greater than who`s?...

Being an engineer myself, I perfectly understand the points being made, that they are not (from an engineering theory point of view) strictly necessary, but would rather run them all the same.

Many years ago, before I understood the `need` for spigots I ran a set of wheels without. Subsequently, I bought a new set of new wheels and took advantage of the free fitting the supplier was offering.

On bringing the car back round, he asked me if I knew that weekend`s Lottery numbers.

Why? Because he reckoned I was extremely lucky to have not had a wheel come off.

Being in the wheel industry, I`d consider him an `expert`...

 

I thought the point of the thread was whether the wheels were safe to use, Chris keeps sidetracking the point onto the use of spigot rings and centreing of wheels. As i said you can make spigot rings for these wheels to ensure centrality. But In my eyes the wheels are still safe to use, though In Chris' and others not safe to use. I know my engineering knowledge is smaller than others, I'm still learning it.

This is the point we really want to discuss is it not?

 

Fair enough...back to the original point...

The original exception to the wheels was the lack of `meat` between the centre-bore, and the bolt holes.

I tend to agree. Regardless of the thickness of the wheel through the bolt holes (as you pointed out), this lack of material looks decidedly dodgy to me.

And there would appear very little/no taper towards the center-bore, so a likely stress-raiser, where a crack could form from the clamping force of the bolts/nuts.

Mag wheels are known for cracking after a time, so this (in my mind at least) would be a likely outcome...eventually.

And, as you may know, when one bolt/bolthole fails, the others follow in fairly quick succession...

 

NO. Read the thread. Page 1, issue of centre bores rapidly brought up, Mike H IIRC.

The 2 matters are interconnected, so stop spitting out the notion I'm diverting the thread

 

The point being, that if the wheel is moving around, it will either stress and damage the bolts, or damage the area around the bolt. 7mm of cast Mg isn't going to last long.

I wonder how the clamping loads stand up to the lateral forces when you have copaslip on the hub, to stop your g60 steels rusting on solid.

Spigots are a PITA to manufacture. If they weren't needed, cost down would have removed them long ago, yet show me ONE manufacturer who doesn't use them?!?!

 

No further questions, your Honour.

Anything more from the Defence?

 

Is this not contempt of court?
The anti spigot ring masif appear to have taken a recess from proceedings without informing the court.

I believe the wheels have fallen off their case TBH!

 

Not a single one of you "spigots will save your life" brigade has shown that the wheel moves on the hub without spigots? Prove that the joint is deisgned to allow movement, and that the bolts don't provide enough clamping force, and that the bolts see a shear force. There is not a single reasoned argument from any of you other than "experiences"

We've provided the argument that the bolts do all the work and don't see a shear force, unless the clamping force is lost

Or just admit that yes they are not essential to the security of the joint, but it does priovde other benefits.

 

Been there, tried it, doesn't work!