Twin turbo Jag V12 mid engined scratch built Zonda

[Davi]

Depends on mix, temperature etc - if you do it when it's freezing and use a low enough mix it can take weeks if ever (guess who made that mistake once...)

It should be mixed / temp controlled to give you just enough working time before it gels in the pot - hour or so to gel then I allow to harden off for a day or two - or cook it if I'm feeling fancy.

e-marked does not mean legal / correct for UK road use on anything you feel like putting them on - for cars you have to have a specific beam pattern. As I say I'm sure I recall reading about someone trying similar only recently so check thoroughly you've got your use and regs correct - you'll be pissed off if you have to make whole new housings because you didn't check something so simple.

[andygtt]

Nick Im in no way trying to diss your car, I think its awsome and as a fellow scratch builder Im 100% behind you as I know its easy to talk the talk but getting on and doing it is something else.

The problems you are having with it moving is exactly what Im experiencing... I had to remake my rear wheel arches by 2 inches recently because it had moved and the body was welded to the chasis and I have a subframe to hold it so how its moved so far is beyond me... but it definatelly had.

I dont want you to build the body only for it to move and crack so badly that you cant even take moulds from it later and end up having to throw it away... that would be criminal.

As a constructive solution, why dont you do what I have done to my buck and build a steel sub frame and bond it into the body? heavy yes but will really help movement.

[Tony 1234]

Nothing to add, just think this is a good thread.

[nicktruman]

andygtt said:

Nick Im in no way trying to diss your car, I think its awsome and as a fellow scratch builder Im 100% behind you as I know its easy to talk the talk but getting on and doing it is something else.

The problems you are having with it moving is exactly what Im experiencing... I had to remake my rear wheel arches by 2 inches recently because it had moved and the body was welded to the chasis and I have a subframe to hold it so how its moved so far is beyond me... but it definatelly had.

I dont want you to build the body only for it to move and crack so badly that you cant even take moulds from it later and end up having to throw it away... that would be criminal.

As a constructive solution, why dont you do what I have done to my buck and build a steel sub frame and bond it into the body? heavy yes but will really help movement.

Hi Andy
My body has a steel subframe (skeleton)! I integrated it into the polystyrene so when i laid the glass fibre it bonded to the steel. When i removed the buck I laid extra layers of glass over the steel on the inside for extra strength.
Where it has sagged is in the areas like air intakes etc.. But I'm sure I can reinforce those parts.What i meant by sagging happened within a few days of laying up. The glass on the bonnet was lovely and smooth. By the time it had cured it had developed wrinkles (gravity?)! I didn't have the same issue on the rear section which is very smooth, although as someone pointed out in another forum distorted on one wheel arch

Maybe if i leave the car looking like "paper mashe" Pagani will buy it off of me to save it being the only Zonda people ever see!

Ah well maybe I should have just done the car in secret and not told a soul - seemed like a good idea at the time. Anyone want to finish it off?

[nicktruman]

Tony 1234 said:

Nothing to add, just think this is a good thread.

Hi Tony welcome to the Nick bash

[Davi]

nicktruman said:

Hi Tony welcome to the Nick bash

Nick it's truly not a bash, we're just trying to offer advice based on our experiences - to help, not to hinder!

[andygtt]

Nick Im really not trying to bash you.... Im building up a body in a very very simlar way to you, people have told me Im doing it wrong as well but its the way that works for me and Im trying to explain the major issues Im having when the cars just sitting still.

Ive had similar bashings about my car on the thread about it, so I know how it feel... but sometimes people come along and give you some excellent help that really moves you on or saves you time (Davi did this with my rear end body design )...

As another suggestion, I have bought some proper filler foam sheets, these are relativelly cheap and when sandwiched between fibreglass make the panels super strong and relativelly light, Ive done this in a few places... maybe you could try laying some of these on the rear of your panels and fibreglassing over them?

[skwdenyer]

nicktruman said:

Tony 1234 said:

Nothing to add, just think this is a good thread.

Hi Tony welcome to the Nick bash

Nick, I think you're a madman. You're exactly the sort of madman we need more of, but that doesn't detract from your madness. But I'm definitely not going to bash you for being mad!

I'm designing a car at the moment. I would never embark on it the way you've done it, because I have absolutely no skill or patience to do the "artisan stuff" with the body that you've done.

In all of that, well done you!

However, it does also seem a shame that you don't take advantage of the skills and experience that are available here and elsewhere. Just because you're prepared to put a great deal of labour into the project doesn't mean that you shouldn't ask and listen to help you use that labour wisely.

The only bashing you'll get from me is if you get lots of good advice, ignore it all, and then moan about it not turning out as you hoped It is, sadly, true that you've been very light on questions on this thread, which just seems a shame.

As for the lights you've found, I like those a lot for another project I've got on the go. Do you have any dimensions you could post? As regards your car and SVA (don't forget that SVA is dead, of course...) then you'll need to get hold of the Construction & Use regulations and read them to make sure that your lights comply. Yes, they have to be "E" marked, but they don't just have to be "E" marked, if you see what I mean.

[skwdenyer]

[quote=nicktrumanIf you guys want projector head lights for you carts i have found the ultimate source! Suzuki AY50 moped lights. Ther are twin Projectors and can be picked up for around £15 a pair.

So that leads to my next project, I need to fabriate and make 2 head light units. But I want them to be great. See picture below, any ideas??




[/quote]

Thinking about the headlight issue a little more, is one of those dipped and one main? In that case you might be OK. The problem with headlights is that dipped beam generally has to dip to the same distance from the front of the vehicle. So if the unit is mounted higher (such as a bike), it has to point "down" more than a car unit would do. Transfer the unit to a car and you find that dipped beam doesn't light anything much at all (but can still be legal!).

[Tony 1234]

nicktruman said:

Tony 1234 said:

Nothing to add, just think this is a good thread.

Hi Tony welcome to the Nick bash

Don't take comments personally Nick, I'm sure everyone is trying to help you

[nicktruman]

Sorry guys i was having a sensitive day, everything piling on top!

I appreciate that my body is awful, I know I should have made it in a different way, But we are where we are! and like Andy says it suited me to do it this way.

So I can't afford to make another body, I can't make a mould then another shell!

So what options do I have.

Andy, what is this board you mentioned? I have no shortage of power (550/600 bhp)so weight isn't really an problem! although at under a tonne it would be cool to stay as lite as possible.

I have some creases and sags, but i also have plenty of commitment and energy to make as good as possible. Surely if I sand the sags down so they go and lay up extra layers of matting on the inside the body will smooth out? I can't see why it couldn't?

I read on a lambo site that the doors are made in situ, by screwing board across the door opening and laying up the glass from inside the car. That way you get an exact fill for the door hole. But to do that i need to get some release agent to paint the MDF with, what do you recommend?

The lights.. They should have been here by now, coming via courier, my luck they will turn up just after my wife gets home and thats me in more trouble

I realise the pattern might not be correct, but there is a plate in the light which targets the pattern that may need adjusting to the correct car shape.

Regards

The Madman!

Edited by nicktruman on Tuesday 21st April 10:59

Edited by nicktruman on Tuesday 21st April 11:23

[skwdenyer]

nicktruman said:

Sorry guys i was having a sensitive day, everything piling on top!

I appreciate that my body is awful, I know I should have made it in a different way, But we are where we are! and like Andy says it suited me to do it this way.

So I can't afford to make another body, I can't make a mould then another shell!

So what options do I have.

Andy, what is this board you mentioned? I have no shortage of power (550/600 bhp)so weight isn't really an problem! although at under a tonne it would be cool to stay as lite as possible.

I have some creases and sags, but i also have plenty of commitment and energy to make as good as possible. Surely if I sand the sags down so they go and lay up extra layers of matting on the inside the body will smooth out? I can't see why it couldn't?

I read on a lambo site that the doors are made in situ, by screwing board across the door opening and laying up the glass from inside the car. That way you get an exact fill for the door hole. But to do that i need to get some release agent to paint the MDF with, what do you recommend?

The lights.. They should have been here by now, coming via courier, my luck they will turn up just after my wife gets home and thats me in more trouble

I realise the pattern might not be correct, but there is a plate in the light which targets the pattern that may need adjusting to the correct car shape.

Regards

The Madman!

Edited by nicktruman on Tuesday 21st April 10:59

Edited by nicktruman on Tuesday 21st April 11:23

Nick

The problem you've got if you try to "sand across" things is that you may sand away some of the glass fibres. If you do that, you'll weaken the structure.

Can you post a close-up photo or two to show areas that you're particularly worried about? That way I (and others) can try to understand a little more about what is happening.

[GreenV8S]

nicktruman said:

Andy, what is this board you mentioned?

Fiberglass is quite flexible, and an open structure will flop all over the place. The way to make a glass fiber shape stiff is to give it thickness. You could just slap more and more layers on to build up the thickness, but that makes it very heavy and expensive. The vast majority of the strength of a thick section comes from the layer near the surface, so you can get pretty close to the stiffness of a half in thick slab of fibreglass by making a sandwich of two thin layers with a half inch thick rigid spacer between them. It's the same way domestic interior doors are made - two thin layers of hardboard are as floppy as anything, but glue then to either side of a cardboard honeycomb and the result is really stiff.

You can achieve the same effect with fiberglass by bonding a layer of foam between two thin fiberglass skins. You can get really useful increases just by making a stiffening rib by glassing over a half inch thich wooden lath or rolled up newspaper. The thing in the middle isn't important in this case - it's the thickness (separation between the two layers of fiberglass) that gives it the stiffness.

Edited by GreenV8S on Tuesday 21st April 21:16

[skwdenyer]

GreenV8S said:

nicktruman said:

Andy, what is this board you mentioned?

Fiberglass is quite flexible, and an open structure will flop all over the place. The way to make a glass fiber shape stiff is to give it thickness. You could just slap more and more layers on to build up the thickness, but that makes it very heavy and expensive. The vast majority of the strength of a thick section comes from the layer near the surface, so you can get pretty close to the stiffness of a half in thick slab of fibreglass by making a sandwich of two thin layers with a half inch thick rigid spacer between them. It's the same way domestic interior doors are made - two thin layers of hardboard are as floppy as anything, but glue then to either side of a cardboard honeycomb and the result is really stiff.

You can achieve the same effect with fiberglass by bonding a layer of foam between two thin fiberglass skins. You can get really useful increases just by making a stiffening rib by glassing over a half inch thich wooden lath or rolled up newspaper. The thing in the middle isn't important in this case - it's the thickness (separation between the two layers of fiberglass) that gives it the stiffness.

Edited by GreenV8S on Tuesday 21st April 21:16

The "thing in the middle" may actually matter a lot, depending upon the type of load applied, the relative stiffness of the materials, and so on.

For your DIY proposition, I would be very wary of trying to use foam in a sandwich construction; the risk of it not working properly is very high.

The "rib" suggestion is a good one. For a large-ish, flat-ish panel (such as a door skin), I would create a grid of such ribs, perhaps every 9 inches apart. You need to make sure that the transition is handled well, however - add a little extra matting at the point where the two layers separate around the spacer to try to discourage localised "splitting".

[andygtt]

foam sheets about 1/2 inch thick, bond these to the back of your body and fibreglass 2 layers over them and it will become extremelly ridgid.

http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Po...

[skwdenyer]

andygtt said:

foam sheets about 1/2 inch thick, bond these to the back of your body and fibreglass 2 layers over them and it will become extremelly ridgid.

http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Po...

If you don't mind me saying, that's a little too simplistic an explanation, don't you think? How are the end- and feature-closures to be handled? How are loads to be carried for, as an example, locks and hinges? What's your recommendation for any double-curvature surfaces? How are any out-of-plane loads to be carried, given that the foam-GFRP interface will be a weak point? How are local out-of-plane deflections to be minimised? What about hydrolytic degradation in the presence of continuous moisture (so there must not be any leaks into the foam layer)?

As regards "fibreglass 2 layers over them", are you not worried that on off-centre neutral axis will cause problems?

Whilst I agree with you that a sandwich panel is a great solution (and I spent 4 years in academia studying them, so I'm definitely a fan!), I'm not so sure that "bung a slab of foam on the back and slap a bit of GFRP over the top" is necessarily going to be all that useful in helping to ensure that the OP - who shows a remarkable degree of persistence and graft in the absence of theoretical knowledge and practical experience! - ends up with "a positive build experience"

[nicktruman]

andygtt said:

foam sheets about 1/2 inch thick, bond these to the back of your body and fibreglass 2 layers over them and it will become extremely rigid.

http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Po...

Andy
This is good stuff!
So how about this for an idea.

I have some folds in the front section which although strong are damn ugly! The body is very strong, I probably laminated way too many times!

As I said before the wrinkles look worse due to the shadows of the camera's flash. Here is a high res picture of the worse wrinkle on the bonnet.

The wrinkles start on the inner surface, which as you know is really smooth. I figure I could fill that inner surface and lay up one sheet of matting on the inside to cover the filled area. Then bod a sheet of this foam sheet over that. Maybe pop riveting it in place so ensure great adhesion? (these would be drilled out afterwards and filled.
Then lay up under as Andy says with 2 extra layers of laminate.

This added to the existing steel frame would give me a very thick nose cone, but still light.

However, I am still left with a finish on the front that needs addressing?

[andygtt]

skwdenyer said:

andygtt said:

foam sheets about 1/2 inch thick, bond these to the back of your body and fibreglass 2 layers over them and it will become extremelly ridgid.

http://www.cfsnet.co.uk/acatalog/CFS_Catalogue__Po...

If you don't mind me saying, that's a little too simplistic an explanation, don't you think? How are the end- and feature-closures to be handled? How are loads to be carried for, as an example, locks and hinges? What's your recommendation for any double-curvature surfaces? How are any out-of-plane loads to be carried, given that the foam-GFRP interface will be a weak point? How are local out-of-plane deflections to be minimised? What about hydrolytic degradation in the presence of continuous moisture (so there must not be any leaks into the foam layer)?

As regards "fibreglass 2 layers over them", are you not worried that on off-centre neutral axis will cause problems?

Whilst I agree with you that a sandwich panel is a great solution (and I spent 4 years in academia studying them, so I'm definitely a fan!), I'm not so sure that "bung a slab of foam on the back and slap a bit of GFRP over the top" is necessarily going to be all that useful in helping to ensure that the OP - who shows a remarkable degree of persistence and graft in the absence of theoretical knowledge and practical experience! - ends up with "a positive build experience"

I agree... but the correct way to advise him is to build moulds!!!... Im trying to offer solutions that will strengthen his existing laid body without adding huge weight, it wont be ideal, but it will help.

[nicktruman]

Here is the latest on my kit car, mechanically its all there now, two more panels to make and then the body to finish off.
http://www.youtube.com/watch?v=AFzTsEO1XQE

however i'm off to Bahrain for 2 years so it will have to wait a while

[craigjm]

Holy thread resurrection!

It doesnt looks like the OP is around anymore but does anyone know where he had the turbo work done on the V12?