Zero Bonnet Manufacture

[Guest greavesy7]

I'm looking at making a new bonnet for my gbs zero as since I have changed the engine I have a few unused holes.

 

I have spoken to gbs who want over £180 which I feel is a lot so was looking to have a go my self as I have access to a folder and a guillotine.

 

But was wondering how was best to form the shape? Has anybody done this before ?

[Shaft]

Just make some plywood formers by using the old bonnet as a template. Space approx every 8 to 10 inches and assemble into a skeletal type frame by screwing timbers between them. Imagine the timbers as a spine and the plywood formers as the ribs.

Fold one sides returns and secure to the former then work it around your frame. Clamp it as you go with another piece of timber running up is length.

As you get going you'll realise £180 is a lot of money..... or is it! Lol.

 

Good luck.

Edited March 30, 2015 by Shaft

[theduck]

Tbh, I'd pay £180 for the lack of a headache doing it myself.

[stevedohc2b]

In build a race car for £500 I am sure he used a lamppost or was that tricky in the Robin Hood videos.

 

Stephen

[fry61]

We made our own bonnet from 0.7mm s/steel -- it is in two pieces hinged at the nose-cone/scuttle centre line. The curved sides were formed around the welding gas bottle --- the right angle bends in the home made bender fixed to the bench edge. The bonnet louvers were pressed by a friend at his works --- BUT HAD TO BE DONE in a flat sheet so marking out is all important. Edge beads for strength/stiffening of the panels was done with modified ball-bearing races in home made jig.

 

Took a long time --- so cost above depends on your view --- have you the skill & time to spare/ do you want the car to be more your creation??

[agent_zed]

If i was to attempt it i'd probably do it the same way i did the rear panel for the 2b. The 2b videos have instructions on it. From memory you mark the centre line and then carefully bend the panel imagining there is a melon in it (from the video not my instructions).

 

you have to bend a bit further than 90 degrees as it will ping back. If you want a tighter curve you need to push down a bit harder.

 

It gives a nice curve as you wont get any marks from a former.

[WallerZ]

I'm also going to have to make modifications to mine due to the engine swap. I'm going to look at getting a sheet of aluminium and bending myself, I may need to find someone to do the louvers though unless a scoop or power bulge is required...but plenty of people about. Can always get a big bit of paper and use that to get the flat shape and add a bit on for the bending.

 

One option I'm going to do is take the bonnet to a local sheet metal place (luckily used to work in the industry) and see what they can do. The hardest part will be the return edge but if someone can do the louvers then that edge will be simple

[theduck]

Just remember louvre need to go in before the panel is curved

[WallerZ]

Just remember louvre need to go in before the panel is curved

 

Yep, will be using the old bonnet to gauge the space, available. Then I'll decide on bulge or scoop or louvers.......probably scoop so there's room for the top mounted supercharger in the future

[theduck]

Just need a big hole for that ;-)