Rivnuts - Weakening Chassis

[robo]

Countersunk rivnuts .http://image.made-in-china.com/2f0j0...ut-Metric-.jpg

If I did want a removable underfloor it would be a lot easier with those self tapping self drilling bolts.http://www.google.co.uk/imgres?q=sel...7&tx=106&ty=95 and the hole would be no bigger than the normal rivet.



I picked up one of these swivel headed rivnut tools off ebay. Dead on for getting in tight spots. http://www.rivetnuttool.net/images/w...ivetsrivet.jpg

Bob.

[flyerncle]

Rivnuts come in all different configerations and you possibly need thin sheet one's MikeB.

The question of weakenig the chassis is a good one,normally if something splits or cracks the fix/cure is to drill a small hole at the end of it,so I would think that unless you can drill a square hole you should have no problems and with square tube you have three other sides to support it.

[nickharding]

Well I thought of using rivnuts underneath as then access to the prop can be gained easily. Now I think about it I can just rivet the bottom panel underneath same as everyone else, and just rivnut the inside tunnel panels and the back panel behind the seats. That might work out better.

[HandyAndy]

Originally Posted by nickharding

Well I thought of using rivnuts underneath as then access to the prop can be gained easily. Now I think about it I can just rivet the bottom panel underneath same as everyone else, and just rivnut the inside tunnel panels and the back panel behind the seats. That might work out better.

What you can do is not "panel in" the underside where the tranny tunnel is, that makes the prop easy to get at from below,

or

fully panel in the whole bottom/underside & make the top of the tranny tunnel interior panel removeable ( this is how mine is ) as I thought getting into the prop would be easier from above rather than from below.

Also worth noting.....The IVA tester "may" want to see inside the tranny tunnel come test time.

cheers
andy

[MarkB]

You only need a few rivnuts to hold things on, but the floor wants to be riveted and bonded as this adds to the stiffness of the chassis. Panel all away across the bottom as you don't need to get to the prop underneath. There are better alternatives to rivnuts but they cost a lot more, check Merlin Motorsport for range of natty fixings. I have some somewhere that came from Jordan GP when my brother worked there and they are made from titanium, superb wee things and it's what they used to hold the nosecone on. The daft blue thing I built used them along with as many NAS bolts and K Nuts as I could(came courtesy of Jordan GP.....)

[wylliezx9r]

Originally Posted by MarkB

You only need a few rivnuts to hold things on, but the floor wants to be riveted and bonded as this adds to the stiffness of the chassis. Panel all away across the bottom as you don't need to get to the prop underneath. There are better alternatives to rivnuts but they cost a lot more, check Merlin Motorsport for range of natty fixings. I have some somewhere that came from Jordan GP when my brother worked there and they are made from titanium, superb wee things and it's what they used to hold the nosecone on. The daft blue thing I built used them along with as many NAS bolts and K Nuts as I could(came courtesy of Jordan GP.....)

Sounds like the fixings would have been worth more than the rest of the car

[nickharding]

Originally Posted by HandyAndy

What you can do is not "panel in" the underside where the tranny tunnel is, that makes the prop easy to get at from below,

or

fully panel in the whole bottom/underside & make the top of the tranny tunnel interior panel removeable ( this is how mine is ) as I thought getting into the prop would be easier from above rather than from below.

Also worth noting.....The IVA tester "may" want to see inside the tranny tunnel come test time.

cheers
andy

Cheers Andy.

Maybe I will do as you said. Panel the underneath as one piece with rivets, and all of the inside/outside bodywork and above the tunnel I will rivnut.