Seat belt supports on roll bar
 

I think that I'm missing something really obvious here. Do the tapped holes in the brackets that fit to the roll bar have to be 7/16". Could they not be a metric equivalent ?

Cheers

Peter

Yes, they could, but the vast majority of harnesses come with 7/16unf bolts.

Fantastic, that was on my ‘list of questions to ask’

Cheers Peter for the question and Sean for the answer

I wondered about this when making my lower harness mounts but the closest metric equivalent i found was a touch larger than the imperial

I was worried that the bolts wouldnt fit through the harness plates, so just went and got the 7/16 nuts as they are easy to get hold of anyway

I dont have any harnesses yet so still dont know if they would have fitted through or not

do you want to borrow some? ;) :)

andy

Cheers lads,

I knew there would be a reason.

Peter

No thanks Andy, as i ended up using the 7/16 thread anyway just to make sure they would fit through

7/16 unf is sort of an industry standard for seat belt brackets. Mr IVA man will specifically look for the correct size bolts and markings on the bolt head. You get these bolts with your harnesses.

AndyH

You can use metric, IVA manual states

Bolts used in structural areas should be of grade 8.8 or better. Such bolts will be marked 8.8 or 12.9 on the hexagonal head, however, cap-head bolts or 7/16" ( 11mm ) UNF seat belt anchorage bolts (with an anodised finish) not marked in this way may normally be considered to be of equivalent strength. Bolts should be M8 or larger.

In ref to seat belt ankoridges

Im using M10

TIlly

7/16 is 11.1125mm, personally i would go larger to 12mm if going metric,just check that a 12mm bolt will pass through the harness bolt hole.