Madabout Kitcars Forum

Madabout Kitcars Forum (https://madabout-kitcars.com/forum/index.php)
-   Bodywork (https://madabout-kitcars.com/forum/forumdisplay.php?f=8)
-   -   Has anyone built themselves a GRP hardtop? (https://madabout-kitcars.com/forum/showthread.php?t=7464)

Mitchelkitman 1st December 2021 16:58

Has anyone built themselves a GRP hardtop?
 
As title.... I intend to build a GRP hardtop for a roadster, with the shape similar to a soft top. Intention being to use it in the Winter. Wanting to keep the weight as low as possible, and a good enough finish to paint (probably matt black paint).

kon 2nd December 2021 08:00

"a roadster"... as in, a z3? If so, should be able to buy all the clips and fixings for the hard top which they made for the car. Shouldnt be too hard to make a thin metal frame which connects all the bits, and then cardboard, parcel tape and grp to connect them. Same with an MX5, and with the price of those hard tops, I wouldnt be surprised if someone has done that a few times already.
I wondered if something like the lightyear fastback top might be a good starting point, if you can find one (or something like it) on this side of the world (light-year are aussie-based).
https://www.miataturbo.net/build-thr...-48089/page28/

Mitchelkitman 2nd December 2021 09:08

Oops... sorry for causing confusion. It's a Calvy Mitchel (hence my user name). - old style roadster. Nearest equivalent is an NG kit car.

Lucky@LeMans 2nd December 2021 17:26

I've seen it done using a timber frame and 1/4" plywood clad with black vinyl. You could glass over the wood and then paint it, depends on what finish you want.

Mitchelkitman 2nd December 2021 19:06

Thanks for your comments lucky. With your experience of GRP, do you consider a horizontal flat panel of the roof with a total of 1200 gsm chopped strand mat would sag over time? If so, maybe adding 5mm nidaplast honeycomb reinforcement and 450 mm layer under may stop it sagging? roughly 1m x 0.8m panel? I'll be grateful for your opinion.

Lucky@LeMans 3rd December 2021 17:18

I'm no GRP expert, best to talk to a laminator for their opinion.

IanA 8th December 2021 18:35

The Tribute guys could probably take a splash mould of the existing hood and then lay up a basic shape for you. Reinforce it with f/g rope as required.

Mitchelkitman 14th December 2021 16:57

Quote:

Originally Posted by Lucky@LeMans (Post 107190)
I'm no GRP expert, best to talk to a laminator for their opinion.

I've tried one of the suppliers to get some guidance - my first thought was to use some coremat in the rooftop to minimise the likelihood of it sagging. the supplier suggested Nidaplast (a honeycomb reinforcement) as it will be lighter than coremat. I used 12mm Nidaplast when I built my caravan, but 5mm will be the one for the hardtop. I don't know any laminators..... maybe they would be reluctant to give their info? But I have a plan. The better weather in Spring may see a start on this, as I plan to do it before I paint the car (in case of spillage!)

Lucky@LeMans 14th December 2021 18:31

Try asking Chris or Dan at Tribute or Gary at Formosa. There's a lot of info on youtube too. There aren't any big secrets , sounds like you are pretty familiar with the stuff having built a caravan ! A small hard top should be quite straight forward.

Mitchelkitman 16th December 2021 17:44

Quote:

Originally Posted by Lucky@LeMans (Post 107232)
Try asking Chris or Dan at Tribute or Gary at Formosa. There's a lot of info on youtube too. There aren't any big secrets , sounds like you are pretty familiar with the stuff having built a caravan ! A small hard top should be quite straight forward.

I agree, but it's always useful to get advice from others - there are small things I could do differently if I was to build another caravan, and that may be useful info for someone else similarly. In fact I'd like to build another (of a different design) if only I could sell the one I've got! I do enjoy playing with GRP

Munky 18th December 2021 16:18

You could always try a conventional Carson top style, using electrical conduit and chicken wire but…
A grp version of a Carson top is covered in detail here:
https://www.jalopyjournal.com/forum/...on-top.240611/

I’ve had the thought of using the existing hood, wrapped in cling film and tinfoil, to create an original mold. Then make a more structured part from that.

Please post if you do move forward with this!

Mitchelkitman 19th December 2021 14:18

Thanks for that. I planned to use foam board, but now have a fiendish plan to save effort (because I'm lazy). I'll report back with my result (should be by Summer)

froggyman 19th December 2021 19:43

I once saw a JC Midge with a hard top that looked just like a soft top. It was only when the owner tapped on it that you knew it was fibreglass and not canvas. Good luck.

Lucky@LeMans 13th February 2022 15:10

Have you managed to make any progress so far ?

Mitchelkitman 13th February 2022 15:51

Pots of resin etc arriving tomorrow - I'll start when the weather gets warmer.

redratbike 21st April 2022 06:55

did you go for it ?

Mitchelkitman 21st April 2022 15:48

I've not had time yet = too busy restoring a mates 60 year old caravan

redratbike 22nd April 2022 05:49

Quote:

Originally Posted by Mitchelkitman (Post 107623)
I've not had time yet = too busy restoring a mates 60 year old caravan

i know how that feels i have been meaning to mould some headlight covers since xmas and just haven


All times are GMT +0. The time now is 00:06.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
Copyright Madabout Kitcars 2022