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General small...big part fabbing query
General small...big part fabbing query
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General small...big part fabbing query
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stevieturbo
stevieturbo
posted 11 Years Ago
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Newbie, but been browsing for a while. I have virtually no experience with this sort of work though.
Hopefully post isnt too long winded.
Not so much for weight reasons, but rust and lack of availability I want to try and make some parts for my car, old MK2 Ford Granada.
I was going to start with a pair of wings/fenders, but might do bonnet/hood first for reasons below.
I had previously had a single skin kevlar bonnet made for me and I still have this mould ( gel/fibreglass mould ). It's been sitting for a few years but looks in fairly good order, although I need to clean it up and change a couple of parts, as well as clean up some scrapes.
Bonnet however took flight at speed a few months back and didnt land too well lol
I think I've a grasp on making a carbon bonnet ok, but my first query is about the chrome strip at the front.
It's a small part, maybe 12-15mm tall at the middle section, and maybe 5mm thick ? Only about 8mm tall at either side. It's metal and bolts to the front edge of the bonnet.
After the flight, I have only 1 of these left on the car, and sourcing another would be nearly impossible. I'm not bothered that the CF part wont be chrome of course. But I want the original shape retained always.
Steel bonnet below.
Given I have a working mould for a plain flat bonnet/hood with no front trim....would it be worth be butchering this to integrate the front trim as one piece with the bonnet ? Is cutting up an existing mould and modifying simple ? The mould would easily be 8-9 years old.
Or how easy/strong would the small chrome part be, if I tried to replicate this in carbon on it's own ? And then just bond it to any new bonnet.
The kevlar bonnet despite being very strong, did a serious amount of flexing at speed, especially the front edge.
So this needs to be taken into account with a small part that's bonded on.
I want to make a pair of wings/fenders as well, and around the front edges these have similar thin chrome trims. Again I'd be happy to integrate these as 1 piece with the wing. But I'd be making those moulds from scratch.
All thoughts welcome...I'm tending to think modify the existing mould so it's all 1 piece will be strongest and best long term solution ?
Bonnet will be painted, so external CF finish isnt super critical.
For strengthening the new part, what is a preferred ? ie to form a carbon box section through the part via the layers.
Some sort of foam square section ? other ?
Thanks
Stevie
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ChrisR
ChrisR
posted 11 Years Ago
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Hi Stevie,
You aren't by chance the same from the DTAforum? If you are... "old" Mk2 Granada..... lol maybe just the shell...
I would try to avoid cutting up an existing mould unless you are pretty hot on composite works already it's very easy to screw it up.
I would be tempted to do one of two things:
1) Buy some trim from www.holden.co.uk (or other restorer / kit car trimming place)
2) Make a separate mould for the trim part and bond on after. - To do this make a small part of the front of the bonnet from the mould you already have so it should match afterwards, then using fillet and sheet wax (or even plastercine) make the bead along the edge and take a mould off that. The main issues will be getting good parts out of it. I would suggest making it in such a way you can cast black pigmented PU resin
Chris
(chrislandy / landychris on other sites)
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stevieturbo
stevieturbo
posted 11 Years Ago
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Thanks Chris. Yep, same Stevie
I doubt trim is available, the trim on my car was only used for approx 2-3 years and differs from 1981 onwards which would be far more common.
Either way, it's back to supply issues. I've been doing some hillclimbs lately and thoroughly enjoying it....but this also carries risks.
I want to make moulds of parts in case I need panels in the future for reasons other than rust.
I think the second suggestion was to make a dummy front part of the bonnet and then use it to fab the trim ?
Or did you mean try and replicate the trim from plasticine ? and then mould around that ?
Any reason for doing that, than trying to make a mould directly of the steel bonnet and trim ? then CF the trim from that part section mould ?
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FLD
FLD
posted 11 Years Ago
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I would mould without the trim and try to source new trim. Have a look here:
http://www.carbuildersolutions.com/uk/trim
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stevieturbo
stevieturbo
posted 11 Years Ago
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FLD (08/12/2014)
I would mould without the trim and try to source new trim. Have a look here:
http://www.carbuildersolutions.com/uk/trim
The trim is a steel/chrome part on the leading edge of the bonnet. Not rubber
Unless someone has new old stock, or from another vehicle there is no way replacement will be available.
Even major panels/doors etc for my older 1980 model are virtually non existent, and some differ from the 1981+ version which on the outside is visually almost the same.
I have some spare panels and doors and a bonnet too fromm a previous car...but after the kevlar bonnet took flight the only other front chrome trim I had got destroyed
I guess it would be far more difficult to make this small thin part on it's own, rather than integrating it into a 1 piece bonnet ?
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FLD
FLD
posted 11 Years Ago
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If you scrolled down that link you'd find this one:
http://www.carbuildersolutions.com/uk/13mm-x-35mm-chrome-flat-trim
and various other sizes.
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stevieturbo
stevieturbo
posted 11 Years Ago
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I did see it thanks, none are anything like the piece on the car.
I'd sooner remove it altogether than put something on that isnt the correct shape. But then I'd need to remove all other corresponding trim too...and I will not be doing either of those.
As said, original shape must be retained one way or another, even if eventually the finish isnt exactly chrome anymore.
If a separate piece it will just be as a backup if the original ever gets damaged.
If I do integrate it with the bonnet and wings when I make CF replacements for them, I'll suffer it not being shiny chrome anymore because of this.
I can stick some sort of chrome tape over it which will be close enough visually.
I'm not looking for alternatives. I'm looking what is the best option for making a replacement from CF and I am leaning towards making it 1 piece with the bonnet, even at the risk of damaging the existing mould I have by cutting it up to do so.
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