Camber bolts self manufacture

I have been looking at a picture of the H-R set and the cost to purchase them of £48.61

In my opinion this is very expensive relative to the quality of the end product.

Would someone be able to give/lend me one in order to see if I could get a batch made up at work.

I'll ask one of my engineers to have a look and see if we can machine some of our existing stock of stainless steel bolts to the exact profile.

If anyone has already done this or found an alternative supplier that can make them up for a few £ let me know.

If I was able to make up a few sets of these, which would include the nuts, washers and spacer, would anyone be interested?

Thanks

Mr T.

Would stainless steel not be really bad to use in a high load application?

I believe so, I think you'd need a none stainless grade 10.9 for this application.

OK

We have bolts in most sizes pitches and materials.

None stainless and 10.9 or stronger it is.

If anyone has any other observations, ideas or recommendations, then feel free to comment.

Not saying it's not a good idea, but have you considered what might happen if one of these was to fail? You could be opening yourself up to a world of pain in terms of liabilities should anything nasty happen.

I'd much rather buy from a large well known company like H + R than some bloke on an internet forum who 'said it'd alright, like.'

I have found these from Fleabay . £22 delivered is still very expensive for two bolts, but more realistic.

I think that based on the ebay price vs the H-R price it would not be worth me trying to manufacture these cheaply for our benefit.

Thanks anyway.

Glad you arrived at that conclusion - camber bolts are of a smaller diameter than standard hub-to-strut bolts but still need to be of the correct tensile rating. because of the design, they also need to be stronger in shear

Leave it to the experts....

ALSO,

NEVER fit to the LOWER strut point, ALWAYS the top, the shear forces are massive in comparison, I did a LOT of work & used some very specialist metallurgy advice in the old days to check out some USA bolts, they were shit, the QA of the material was that of Gr 8.8 on a good day going down hill with a rocket propelling you.

No less than 12.9 IMHO ( as the shank will only be a M10 ).

Don't think stainless is tough, fatigue resistance is crap

HTH

Thats not quite true. The shear force on the joint is resisted by frictionby the clamping force. The clamping force is created by the end load on the bolt when it is tightened. Assuming both the upper and lower bolt are tightened to the same torque, this is the maximum load the bolt will ever see.

Which is exactly my point - the torque setting for the camber bolt is much less - just 55 lb-ft with the Eibach bolts

So, are THESE any good? Is the seller reputable and are they likely to be genuine Eibach bolts?

yer there fine!

im doing a group buy and we can get them cheaper mate!!
see the group buy section!

its only £1 cheaper...

by the way, the group buy camber bolts are Eibach!

ERM, wrong !

Friction may be related to a clamping force applied by torquing up a bolt ( and this is assuming that both surfaces are DRY / clean of debris etc )

HOWEVER that does NOT mean that both bolt areas experience the SAME force on them, BENDING MOMENTS anybody ?

Fit them to the bottom & let me know how long you live with "athletic driving".

I really hope someone doesn't ignore my advice.

oh, and 55 lbs of torque is no good, on an standard M12 I would expect about 250Nm ( whatever that is in pounds, say 175 lb ) This means the clamping force is Already less than stock = movement = bolt shear.

incidentally 55lb is only about the max for a Gr 10.9, fail

The maximum stress the bolt sees in this application will see is when is is originaly tighted. The joint is kept together by friction not by the bolt sitting against the side of the hole. (unless the joint is uncorrectly designed) The bolt will not see any more stress in service than when it is stationary. The bolt does not see any bending at all, the joint however does and this is different at the top and bottom

Ok Pal, my fault, It TRULY is a STATIC application & not subject to vibration, SHOCK loading etc / dynamic force placed upon the joint assembly ( note the word assembly ).

I apologise

Anyhow, this is NOT aimed at scaring persons from buying a camber bolt ( hell I've used them ) however remember it's limits ).

HTH.

Taz - that's what I thought, but the instructions with the Eibach camber bolts were very clear on the torque rating, stating it was critical

Could someone that's taken part in the camber bolts GB please confirm this torque value?

You need to investigate the design of bolted joints . The pre load in the bolt due to the initial torgue should exceed any load that is seen in service. This means the bolt will not see any additional load.

Any sidewides forces on the strut caused by cornering, braking, or accelerating will put less load on the upper part of the joint than the lower, however any verical load on the strut by load transfer in cornering, or bumps in the road (Shock) will actually load the upper part of the joint more than the lower

rather than using camber bolts, can't the hole be filed eliptcal in the shock absorber as some of the coil over are made

Yes, that's another way of doing it, but there is no method of adjustment, other than loosening both bolts and angling the hub by hand

the beauty of camber bolts is that rotating the bolt actually adjusts the camber (because there's a cam in the middle of the bolt)

I didn't realise they had a cam in the centre, just thought the centre was a smaller diameter. This go somewhere to explaining their cost

As I said previously I commissioned a mate from work ( by the way he is a VERY WELL qualified metallurgist, mainly EX MOD , Nuclear, Automotive & has extensive NDT knowledge ).

When I drafted a drawing of the fit ( noting that the OEM uses a fitted bolt setup with a close fitting shank to act as a load bearer if the bolt looses pre-load, i.e. corrosion / poor fitting ), he was alarmed to say the least.

Pretty much reinforced my own conclusions, BTW this company was sent the results ( in a discreet way, NOT Eibach / H&R as their products are VERY good , but an American company ).

HTH chaps

@ Ecrab, the design is quite intricate, it's a casting, rather than a forging ( on the cheaper types ).

Taz are you saying the bolts are cast rather than forged ?

I know / have it on some recollection that the very expensive ones are from a forged stamping which then is machined...

I am pretty sure that the cheap jobbies are just a casting / pressure casting ( certainly the spec they were assumed to made to, they didn't even meet ).

Also, the standards of underhead radii, threadforms etc all pointed to a shocking design.

This particular bolt is NOT the Eibach / H&R brand, however I am happy to let you know the maker by PM.

Joe AKA Dr Frag was the unfortunate victim of this make & I did a lot of correspondence in the old days to assist him

HTH

I remember Joe's post about snapping his bolt - proper brown trousers moment

IIRC Didn't Joe has his camber bolt in the wrong hole though - causing excessive stress to the bolt ?