'Bending' Fibreglass

[450Nick]

Just fitting my new front end this week and I've got the mounts all on and glassed up and it sits pretty well on the car but I've noticed that the front of both wheel arches on the new front end (Tuscan racer) are a little bit too narrow for the body of the car, so there is a step where they line up. I need to 'bend' them both out around a centimetre but I'm aware that fibreglass doesn't bend as such. If I were to gently heat the affected areas and put some bracing on to hold the two areas in their desired locations, would I be able to reset their cold position? Or am I going to have to come up with some sort of fixing to hold it in place?

I'm not sure why this has happened in the first place as the front end is out of a standard mould... Unless my front wings have been widened slightly? Actually thats entirely possible as the back has been widened.

[Conian]

how much length of glass is there to spread the 'bend' over
for 1cm i'd think it could bend that far without peril, i'm no expert though

[450Nick]

Theres a fair bit of length for it to bend over, and its quite thin glass anyway so hopefully it will bend, I'm just not sure if it will stay there once bent!

[teamHOLDENracing]

You can't 'thermoset' fibre glass - i.e. heat it, bend it and allow to cool in new position. You should be able to splay the bonnet open by 10mm each side without damage, and use ali L section pieces on the tops of the wings to keep it there.

Its quite common - none of the factory bonnets I had during 2003/4 fitted - you should know by now that nothing TVR, especially race TVR, ever fits perfectly, it always need fettling

[450Nick]

Hmm you're quite right Andy on the fit front! Right then it looks like I'll be cracking the fibreglass kit back out to put some bracing into the wings... Might have to be stronger than ally though as from memory it takes a reasonable force to hold in the desired position even though its not much movement at all. I'll have a look tonight and do some head scratching...

[NTEL]

Nick, as I don't have a tuscan I can't quite visualise what your trying to do but when I made the bonnet bulge in the Taz bonnet I was faced with a similar problem with bending fibreglass.

What I did was to deeply score the back of the sheet using a grinder, stopping just short of the surface, in a number of places. The sheet was then easily "bent" to form the desired curve.

This was then temporarily braced with duck tape whilst I laid up 1 layer of glass on the back. When dry it kept its new shape. Don't know if this method would work in your case though.

[teamHOLDENracing]

Am I right in thinking that if you place the bonnet centrally on the car, the bonnet sits 'inbound' on the front wings by 10mm each side?

If so that's quite common, and overcome by having a vertical edge (a piece of ali L section would do the trick) on the tops of the wings over which you would pull the bonnet should be all you need to do, particularly if you use a sprung bonnet clip on the front edge of the wing to hold it down, and bonnet pins on the windscreen scuttle

A 50mm long bit of ali L section riveted in the right place is probably all you need

[tbdgriff500]

you lot are hilarius
have you seen the gaps above my wheel arches !!
40mm deep ali channel just to take up the gap!
put it this way Nick, once you have crashed it a couple of times you won't give a st anymore like me !
i find the prettier they are the more you crash them, just ask Kev

[450Nick]

Thanks Andy, yes you've understood my poor explanation correctly! The two edges sit slightly inbound around the wheel arch. Hopefully some ally angle will sort it! If not, I'll have to give Dave's method a try!

@ Tim - Oi, boyhood dream of a Tuscan Racecar is in progress of being realised, and its so far looking st hot. I'm buggered if my wings aren't gonna line up!

Edit: I've currently just got an ally bar sitting in a couple of big ally hooks at the front, then a couple of aero catches to go up by the scuttle. Would some side fixings be a good idea too?

Edited by 450Nick on Wednesday 6th October 17:24

[450Nick]

Here's a pic I took last night of the prob (propped out by the black bar in this case)

[tbdgriff500]

that is loooking gooood

[tvrolet]

You might be tempted by my wee solution - maybe too extreme for a full-on racer, but it does keep things lined up. I wanted the bonnet to fit exactly and couldn't use the 'normal' site spring clip thingies.

I've two 10mm bolts going up through the wing - one at the front, one at the rear on each side that a bit of 10mm hose sits over as a sleeve. I then glassed round the hose on the bolt to create a sort of glassfibre 'thimble' type shape; it'll slip off once it's dry by squashing the hose. I gave it a wee smooth-down to make it a sliding fit on the 'pins'. With the 'thimbles' in place on the pins I clamped the bonnet exactly where I wanted it and from underneath/behind glassed the 'thimble' things to the bonnet. It then needs some more reinforecement once everything dried and the bonnet opened again and you can get in to work properly, but essentially the bonnet now sits tight on the 4 'pins' and has no side-to-side (or forward backward) play. You can make out the front 'pins' in this pic (I had spare Samco blue hose, so the bonnet benefits from silicone mounting ), bit not the 'sockets' on the inside of the bonnet, but you can work it out. The front 'pin' is in the pic and would (if I understand your problem properly) solve the 'narrow' bonnet; the rear 'pins' are outside the pic but are in the 'wide' bit of the wing just behind the scuttle in front of the door. I also reinforced the area in the wings where the bolts/pins go through.



In truth that's only half of it, since I 'remade' my bonnet a few cm deeper round the edge as it sits higher to clear the taller engine, then glassed it on to the car to get a perfect fit and re-cut the panel gap, but I was a bit anal about geting a perfect fit....

[teamHOLDENracing]

450Nick said:

Thanks Andy, yes you've understood my poor explanation correctly! The two edges sit slightly inbound around the wheel arch. Hopefully some ally angle will sort it! If not, I'll have to give Dave's method a try!

@ Tim - Oi, boyhood dream of a Tuscan Racecar is in progress of being realised, and its so far looking st hot. I'm buggered if my wings aren't gonna line up!

Edit: I've currently just got an ally bar sitting in a couple of big ally hooks at the front, then a couple of aero catches to go up by the scuttle. Would some side fixings be a good idea too?

Edited by 450Nick on Wednesday 6th October 17:24

The L section will sort you out. In terms of bonnet fixings, you need it solidly bolted at the front so it will tip forward (some people mount them through rose joints). You'll then need bonnet clips (aero or conventional) along the trailing edge through the windscreen scuttle at both sides and in the middle. You'll also need one in the middle/front of the bonnet to a pin mounted on a metal rod attached to the chassis. You'll think you don't need it until you go to a fast circuit like Snett and your bonnet will 'inflate' and try and rip itself off. And yes, a couple on springs just behind the wheel arches would also be a good idea. Have a look at what other people are running to see.

[450Nick]

Thanks for the suggestions guys, I'll have a think tonight and see what will work for my car.

Andy, the bonnet fixings I have at the front at the moment are a pair of large ally hooks. The bonnet has an ally bar glassed into the front and sits down into the hook and then slides back. The aerocatches then lock it in logitudinal position and two guide pieces on the ally bar in the bonnet secure it laterally. Very strong and means that you can hinge the bonnet up normally but can easily slide it forward and off with no bolts. I was thinking of putting a third aero catch in the middle at the scuttle but not thought about one in the middle of the bonnet? Is this the only option or could I maybe put a couple of rearward facing naca ducts in to relieve the pressure?

The next obstacle I face is making up a splitter.. I was thinking of bolting it to the chassis so it can take lots of force and easily be replaced if ripped off without damage to the bonnet. Anyone tried this? I just don't think the bonnet is strong enough not to deflect at speed

[Keithyboy]

450Nick said:

The next obstacle I face is making up a splitter.. I was thinking of bolting it to the chassis so it can take lots of force and easily be replaced if ripped off without damage to the bonnet. Anyone tried this? I just don't think the bonnet is strong enough not to deflect at speed

Nick - talk to Neil S - he's done this with his Tuscan.

[kg55]

tbdgriff500 said:

you lot are hilarius
have you seen the gaps above my wheel arches !!
40mm deep ali channel just to take up the gap!
put it this way Nick, once you have crashed it a couple of times you won't give a st anymore like me !
i find the prettier they are the more you crash them, just ask Kev

know what you mean tim since we stopped doing showroom repairs i have not hit anything (except grahams truck in the paddock LOL) and it still looks the tits

[450Nick]

Keithyboy said:

450Nick said:

The next obstacle I face is making up a splitter.. I was thinking of bolting it to the chassis so it can take lots of force and easily be replaced if ripped off without damage to the bonnet. Anyone tried this? I just don't think the bonnet is strong enough not to deflect at speed

Nick - talk to Neil S - he's done this with his Tuscan.

Thanks Keith, will do!

[Neil_S]

teamHOLDENracing said:

450Nick said:

Thanks Andy, yes you've understood my poor explanation correctly! The two edges sit slightly inbound around the wheel arch. Hopefully some ally angle will sort it! If not, I'll have to give Dave's method a try!

@ Tim - Oi, boyhood dream of a Tuscan Racecar is in progress of being realised, and its so far looking st hot. I'm buggered if my wings aren't gonna line up!

Edit: I've currently just got an ally bar sitting in a couple of big ally hooks at the front, then a couple of aero catches to go up by the scuttle. Would some side fixings be a good idea too?

Edited by 450Nick on Wednesday 6th October 17:24

The L section will sort you out. In terms of bonnet fixings, you need it solidly bolted at the front so it will tip forward (some people mount them through rose joints). You'll then need bonnet clips (aero or conventional) along the trailing edge through the windscreen scuttle at both sides and in the middle. You'll also need one in the middle/front of the bonnet to a pin mounted on a metal rod attached to the chassis. You'll think you don't need it until you go to a fast circuit like Snett and your bonnet will 'inflate' and try and rip itself off. And yes, a couple on springs just behind the wheel arches would also be a good idea. Have a look at what other people are running to see.

Agree with Andy on this. That's how my car was done by the factory and works ok. What you also have to allow for is how the heat from the engine makes the fibreglass go soft too. After a race it is consideraby more flexible than before the start and so needs to be located as suggested.