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Thread protrusion
Rogthebandit - 18/2/12 at 11:01 PM

Hi

Just building up the suspension on the mk. Can anyone give me advice on the thread protrusion for the iva inspection. I have about 2 threads showing past the nylock. Just want to make sure them there testers are not going to fail me when I get it tested. Also do the suspension bolts need to be greater than 8.8s ?

Cheers

Rog


daviep - 18/2/12 at 11:21 PM

2 threads is good enough as is 8.8


designer - 19/2/12 at 09:06 AM

The minimum thread projection is 1 1/2 threads.


britishtrident - 19/2/12 at 09:34 AM

As protruding threads as above .. so no worries.

8.8 or grade 8 are fine for suspension bolts provided they are adequately sized to start with but 10.9 is better..


Rogthebandit - 19/2/12 at 10:04 AM

Cheers chaps, that's sound, I shall carry on with the build :-)


Davegtst - 22/2/12 at 06:30 PM

I've just checked mine and I only have 1 thread at the most. Looks like I need longer bolts which is strange as these were the bolts mk supplied. Would there be any problem using stainless bolts?


Andybarbet - 22/2/12 at 06:52 PM

As far as I know stainless bolts are a no go on suspension due to being brittle compared to steel ones.

I will let the Locost fountain of knowledge correct me ive been mis-informed


iank - 22/2/12 at 07:14 PM

quote:
Originally posted by Andybarbet
As far as I know stainless bolts are a no go on suspension due to being brittle compared to steel ones.

I will let the Locost fountain of knowledge correct me ive been mis-informed


I believe you are correct, I believe stainless would likely fail IVA if used on suspension.

8.8 is said to be best for suspension (iirc there are two theories either as an 8.8 bends rather than snapping like harder 12.9 if you hit a curb too hard you're likely to keep the wheel all be it at a funny angle, or it will protect the chassis more by breaking where the chassis will tend to bend and suspension brackets rip off before a 12mm 12.9 lets go.) Take your pick, but 8.8 passes IVA fine.


Stott - 22/2/12 at 07:15 PM

quote:
Originally posted by Davegtst
I've just checked mine and I only have 1 thread at the most. Looks like I need longer bolts which is strange as these were the bolts mk supplied. Would there be any problem using stainless bolts?



Don't use stainless for the reason above

As for a solution to your problem get a load of form b washers and replace all your normal ones which will save you changing all the bolts.

They are about 1/2 - 3/4 thickness so will get a little more thread showing.

ATB
Stott


britishtrident - 22/2/12 at 07:23 PM

Are flange nuts accepted by "the powers that be" as self locking ? they are generally a lower height (height = dia) and don't require washers.


Neville Jones - 23/2/12 at 10:39 AM

Flange nuts aren't accepted, as they aren't self locking. I've even had aero stiff nuts questioned.

Two threads protruding is mandatory for IVA.

Above is for Southampton and Reading, other stations may differ in interpretation.

Cheers,
Nev.


loggyboy - 23/2/12 at 10:55 AM

quote:
Originally posted by Neville Jones
Above is for Southampton and Reading, other stations may differ in interpretation.

Cheers,
Nev.


Reading?


Davegtst - 23/2/12 at 03:08 PM

quote:
Originally posted by Stott
quote:
Originally posted by Davegtst
I've just checked mine and I only have 1 thread at the most. Looks like I need longer bolts which is strange as these were the bolts mk supplied. Would there be any problem using stainless bolts?



Don't use stainless for the reason above

As for a solution to your problem get a load of form b washers and replace all your normal ones which will save you changing all the bolts.

They are about 1/2 - 3/4 thickness so will get a little more thread showing.

ATB
Stott


Thanks, i did think of this but i don't think it would be enough. I have just bought a load of 8.8 bolts 5mm longer which are a lot better. It would drive me mad if i failed the IVA for the sake of £10 worth of bolts.


britishtrident - 23/2/12 at 05:06 PM

Thread copied for future reference.


Neville Jones - 23/2/12 at 06:11 PM

quote:
Originally posted by loggyboy
quote:
Originally posted by Neville Jones
Above is for Southampton and Reading, other stations may differ in interpretation.

Cheers,
Nev.


Reading?


Yep, used to be an SVA station in Reading. I've use Southampton nowdays.

Cheers,
Nev.


jacko - 23/2/12 at 08:10 PM

Why not fit half nuts you can buy them and they will give you enough thread
M12 HALF NUTS / LOCKNUTS 12mm BZP (Pack 20) | eBay

[Edited on 23/2/12 by jacko]


phelpsa - 26/2/12 at 03:22 PM

Kaynuts are generally quite slim and aerospace certified.

http://www.nasbolts.co.uk/acatalog/Metric_K_Nuts.html

Not cheap though


MEERKAT - 28/2/12 at 06:21 PM

Can you have too much thread showing?