Chaps,

I've finally got the engine bay totally finished and thoughts have turned to how to source a bonnet.

I like the look of Alu but could do with the convenience of GF

Need opinions please:

1. What looks best? Alu or Coloured Glassfibre. (Car has alu back and side panels)

2. My GF scuttle and nosecone came from Locost Ltd - they're MIA, so does anyone know who has they're moulds and if their product is any good? or if any other firms make a bodywork set that might match?

3. How hard is it to "make" an alu bonnet? The "little book of lies" makes it look suspiciously easy.

4. Looks to me like luovres in the bonnet will fail SVA on edges, any views?

TIA

Dave

I'm finding it devilishly hard to make. Using the "MEASURE 50 TIMES CUT ONCE" method, I keep on getting it wrong!

Bonnet = Nightmare (IMHO)

Hardest job I did on the car.

If you can get a glassfibre one to fit I would.

Didn't Locost Ltd "morph" into Luego?
Try them

Cheers

Chris

I made my bonnet before fitting the engine by raising the front on ramps,putting a sheet of aluminium over the gap between the scuttle and nosecone and taping it down, just to locate it. Then I used a ratchet strap hooked on under both sides of the bottom chassis rails and tensioned it to pull the sheet round. Then I got underneath and drew round the inside of the sheet with a marker pen. Cut round the line and allow some for errors then trim it gradually to fit. The measuring method usually fails because the scuttle end isn't square, more of a shape.

yours, Pete.

[Edited on 14/9/03 by Peteff]

How about making a flat pattern out of 10oz pattern paper by fitting it to the car and marking the radius tangents from underneath like the guy above suggested then transffering it to metal?

cant wait til get where you are Fletch

Cheers Chaps!

Just spoke to Grant at Luego Sportscars.

Chris, u r spot on, Luego use new versions of the Locost Ltd Moulds and have confirmed that their satandard bonnet will fit Locost Ltd nose and scuttle.

Any ideas about the quality of luego fibreglass because to save a lot of grief I am very tempted to buy the bonnet from them.

Not too bad @ £125 inc vat and £25 !! p&p

ps thx for the diy alu tips - trouble is I cant get in my engine bay to mark up from underneath anymore, theres a working engine in the way now.

ATB

Dave

[Edited on 15/9/03 by Sideways 2 Victory]

I've used both methods, and came up with sides that were slightly short each time. I'm about to start my third and I hope final attempt!

The best method I've seen, and which I intend to use, is to make a wooden mock-up.

This is an exact copy of the shape and position of the bulkhead, nosecone, and chassis members. If you put a lot of effort into getting this accurate then making the bonnet is less of a hassle (not 'easy', just 'less of a hassle'!)

Once it fits the wooden plug, then it should go straight onto the car. Allegedly.

David

id always thought this would be one of the easier bits......could be wrong by the sound of it.

My plan is an amalgamation of peteff, thekafer and davids ideas.

make up a series of wooden 'bridges' over the engine bay (engine allowing!) to act as formers, with suitable runners to support the bonnet at 150mm or so intervals. Make up a template over this assembly.

Cut the alu to shape to suit template.

At the points of maximum bend, use the soap and blowtorch annealing method. (my alu is 2mm....) this might make the bonnet bit soft, but I can always put something behind the curve after its finished to give rigidity.

Then use peteff's straps idea. However, i hve found annealing makes the sheet so easy to bend I recon it could be done by hand. I had to put approx 1 metre long 60mm curves in my rear panel ast it meets the car sides and I did that mostly by hand!

atb


steve

[Edited on 15/9/03 by stephen_gusterson]

annealing? is that heating it to form it and it stays where you have bent it to? ie looses its "memory" as such?

Cheers

Colin

when you anneal aluminium it stays soft for quite a time....like months. It makes the material a lot more pliable and easier to work with. it doesnt need to be formed when hot. once treated, its bendy. Just dont go overboard or it will be too weak!

atb

steve

Annealing is a process that allows the material to revert to it's malleable, (soft / workable) state. Aluminium will work harden and age harden, ie when bent the bent bit will be harder than an unbent bit. Try it, bend a small bit of alloy in your fingers and then try to bend it flat again. Age hardening is a slower process where the material hardens over a period of time depending on conditions.
As for producing a bonnet or anything similar, if you have trouble forming the shape you want then anneal the area of the bend, (repeatedly if required), the action of forming it will return some if not all of the 'hardness' and age will do the rest.

PS Not that relavent to a bonnet but most failures in alloy sheet constructions are caused by the material hardening to such a point that it becomes too stiff and cracks.

Mick

At the points of maximum bend, use the soap and blowtorch annealing method.
steve

[Edited on 15/9/03 by stephen_gusterson]

Get a bar of cheap hard soap. Rub it dry onto the aluminium, leaving a trail of soap all over the metal. Heat the metal with a blowtorch until the soap trails go dirty brown or black.

The metal is then annealled! The soap tells you when to stop heating, as shortly after this point the aluminium will disappear...

cheers,

David

who thinks of these weird and wonderful aids to working?

I saw on here a while ago a post saying that to remove the black residue when polishing ally dip the polishing cloth in flour, ......i though nah what are they going on about,............got home and had to give it a go, ........result.......cut my polishing time in half, who in their right mind would have thought to try that?

Col

Its like the old trick I learned from a retired car valeter.

Mix T-Cut with Polish - use sparingly - 75% quicker, less paint is cut off and you get a nice polish to.

Not quite so far-side as the flour thing but simple and someone must have thought

"blx to this i'm gonna save some time ere and get down the pub early"

ATB

Dave