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On the subject of nuts and bolts
The Doc - 13/2/05 at 07:23 PM

Hi folks,
Obviously we know about nylock nuts on suspension linkages etc, but what's the deal on things generally - say the bottom swivels etc? Is it best to assume spring washers all round?

Also does the SVA man actually look to check the tensile value of bolts etc? I'd like to know this before I paint everything for the final build and find I have to take it apart again!

Cheers Mike


RoadkillUK - 13/2/05 at 08:05 PM

If by bottom swivels you mean the lower ball joints on the front suspension, you definately need locknuts. I accidentally left 'normal' nuts on and failed my pre-SVA MOT.


The Doc - 14/2/05 at 01:31 AM

I mean the the bolts that hold the ball joint units to the wishbone as opposed to the nut holding the upright to the taper


Marcus - 14/2/05 at 08:06 PM

Definitely use locknuts, it's just not worth the risk. I don't think it's an SVA requirement, but the fact that nearly all my nuts are nylocs got the thumbs up from Mr SVA.
BTW, make sure your master cylinder is held on with locknuts, they argued mine wasn't properly secured (typical, the only nuts I forgot about)

Marcus


dblissett - 14/2/05 at 08:22 PM

yes you must have nylocs on the ball joint fixing bolts and they must be high tensile bolts
mr sva will look for the rating on the bolts
ps you must use ht bolts for the suspension also
cheers dave


britishtrident - 14/2/05 at 08:43 PM

quote:
Originally posted by Marcus
Definitely use locknuts, it's just not worth the risk. I don't think it's an SVA requirement, but the fact that nearly all my nuts are nylocs got the thumbs up from Mr SVA.
BTW, make sure your master cylinder is held on with locknuts, they argued mine wasn't properly secured (typical, the only nuts I forgot about)

Marcus


He was out of order on the master cylinder mounting plain nuts with plain and spring washers are more than sufficient.


DarrenW - 15/2/05 at 10:39 AM

Ive used nylocs right thro on my build. General rule seems to be better safe than sorry.

Hijack follows -
I gave my father my tie rod (std sierra tie rod ends) end lock nuts before i put my front uprights on etc. He weakened is taking them on and off several times. BIG MISTAKE - i cant find replacements. Strange thread. Seems to be 10mm diameter but has same thread form as 1/4 whitworth!!! If anyone knows what they are or where to get them please U2U me.


dblissett - 15/2/05 at 07:03 PM

are you sure they are metric its just that 3/8 is close so it could be 3/8 whitworth
cheers dave


wheelsinsteadofhooves - 15/2/05 at 09:04 PM

m10 fine thread me thinks. maybe imperial though. (i'm usually wrong)


britishtrident - 15/2/05 at 10:14 PM

If you mean the nuts holding the taper to the steering arm they could be anything but my first suspect 3/8 UNF (24 tpi)


3/8dia BSF has 20 tpi same as 1/4 withworth

10mm Metric fine has a pitch of 1.25

[Edited on 15/2/05 by britishtrident]


wilkingj - 15/2/05 at 11:17 PM

I think you will find that all "Mission Critical" nuts need to be of the lockable type ie Nyloc, or Castelated with a split pin. Its a MoT failure point.

For the minimal cost involved I am fitting all Nyloc nuts.
You are spending at minimum £2000 building a car, and you want to reduce its safety by skimping on and extra £20 or less on the higher cost of Nyloc nuts over std ones.

Dont spoil the ship for a Half P's worth of Tar.

You know it makes sense.


dblissett - 16/2/05 at 08:57 PM

"£2000 min
my book says you can build one for £250 so it must be true


clbarclay - 16/2/05 at 09:39 PM

£250! that barely covers SVA

appart from that £250 could still be do able, if all the donnor parts were still plentifull.
Fond a scrappy with a cortina in it, no front uprights mind.
Its a pain in the arse, when you jump on a band waggen 9 years too late.


NS Dev - 16/2/05 at 10:48 PM

quote:
Originally posted by The Doc
Hi folks,
Obviously we know about nylock nuts on suspension linkages etc, but what's the deal on things generally - say the bottom swivels etc? Is it best to assume spring washers all round?

Also does the SVA man actually look to check the tensile value of bolts etc? I'd like to know this before I paint everything for the final build and find I have to take it apart again!

Cheers Mike


Don't use spring washers!!!!

Use Nylocs, or any other locking nut (K-nuts etc) but spring washers are utter crap and should never be used on anything more technical than a gate!

Really can't be bother to explain why now, but they are crap and should NEVER come near to a car.


Rorty - 19/2/05 at 11:43 PM

I would agree with NS Dev; don't use split washers, they're for farmers. Use either Nylocs, or better still, "all-metal elastic stop nuts" such as K-nuts.
And also use proper hardened washers too, not the farmer's grade of mild steel washers, They can distort and "hammer" with the result they loosen the bolted joint. Use non-ground hardened washers with the rounded edges against the bolting surface.
One bloke I came across said the rounded edge went towards the nut to prevent damage to your fingers when initially tightening the nut!


clbarclay - 19/2/05 at 11:56 PM

Whats up with you rusty, sounds like you've just driven 20 miles stuck behind a tractor.

My experiance of farmers is if the use spring washers (in fact any washers at all) it is because they haven't lost the origional ones yet.


Northy - 20/2/05 at 10:56 PM

quote:
Originally posted by Rorty
with the rounded edges against the bolting surface.



Why? Guess why I'm asking!
Got me worried now.....


Rorty - 20/2/05 at 11:06 PM

quote:
Originally posted by Northy
quote:
Originally posted by Rorty
with the rounded edges against the bolting surface.



Why? Guess why I'm asking!
Got me worried now.....

It prevents the sharp edges digging into the material and fretting or causing stress risers.
I once saw a car being towed back to the pits minus one wheel; the two-piece wheel had been tightened uo OK with the correct nuts and hardened washers, but the sharp edges of the washers had nice and neatly punched through the thin aluminium wheel shells. It obviously didn't happen just there and then. The damage must have been progressing for some time and neither the owner nor scrutineer had noticed the tel-tale cracks. On examination, another wheel was going the same way. So much for stripping and checking everything between races!


clbarclay - 20/2/05 at 11:15 PM

Theres no point stipping everything if you don't know what your looking for. I wounder just how many of us know about all the small things like which way up to put washers on. To be honest I didn't.

Another similar problem are is circlips, the holes on them are tapered. so if you manage to get one on the wrong way round, you can garanty it will be a pain to remove again. Remember small side of the hole towards the circlip pliers.


Rorty - 20/2/05 at 11:31 PM

quote:
Originally posted by clbarclay
Theres no point stipping everything if you don't know what your looking for. I wounder just how many of us know about all the small things like which way up to put washers on. To be honest I didn't.


That's the difference between a novice and a seasoned racer. If you don't know, don't let pride prevent you from asking. Most people would prefer somone who asks endless questions to some know-it-all who causes accidents and damages others cars.
There's nothing like knowledge gained from experience, and there are no short cuts; you have to put in the miles.
If you join a club, other members can help guide you, and the scrutineer should soon let you know where you're going wrong.
It pays to get on the good side of scrutineers and remember, they're always right and have the final say!


Hellfire - 21/2/05 at 12:40 PM

BT I agree with you about the SVA man being out of order. However, as there is no real law, it is upto the individual on the day. That's life isn't it?