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21 minutes ago, Nick Jones said:

Cool stuff.  Looks fairly tricky.  We used a vacuum storage bag and hoover to glue fresh vinyl onto a dashtop, which worked satisfyingly well, but this is a whole other level.

Was thinking of trying this for the front valance as I'm probably going to make what is a rather vulnerable panel with the air dam out of glassfibre rather than carbon.

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Back to suspension. Rear end first!! At the back it's about managing swing axles to keep camber and track changes to the minimum so as to keep as much of the rear tyre on the road which all comes

The flash from the split will be visible on the part and need cleaned off. The overrider is a really awkward shape a bit of a 'draw' but not a lot and also quite small and difficult to grip. The

Well it came out of the mould in one piece and seems pretty robust. Ridiculously light too. There was a little it of sinkage of the gelcoat into the carbon weave along the bottom edge of the lid

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7 hours ago, Escadrille Ecosse said:

Cheers mate. Working my way up to a whole bonnet. Maybe.....

Well, since you mention it, I do have a GT6 chassis and V5C at the side of Loch Lomond that needs a body..................

Joking aside, I am in awe!

Phil

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5 hours ago, thebrookster said:

Well, since you mention it, I do have a GT6 chassis and V5C at the side of Loch Lomond that needs a body..................

Joking aside, I am in awe!

Phil

Well if someone can come up with a mould for the tub I might be interested :biggrin:

But cheers Phil :thumbsup:

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Meanwhile I've been out in the garage taking a peek. The stuff has had only 14 hours to cure so far so still a bit to go but vacuum is holding.

Only dropped 6 inHg overnight so pretty pleased with that and it pulled through a good few cc's of excess resin so hopefully have good compaction and reinforcement to resin ratio. 60:40 is what we're trying to aim for in a vac infusion part.

This is compared to maybe 40:60 for an open hand layup, so 20% more resin. Pre-preg layups have similar ratios to vac infusion but are more suited to larger volume manufacture.

 

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24 hrs curing and still not quite there. The bit that was on the heated pet mat is done. The two ends, even though I had them wrapped in a blanket are still ever so slightly soft.

Nevertheless I had a go at removing all the consumables. Vac bag first

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Then the infusion mesh and peel ply. Having seen the videos I got the impression that this bit was quite physical. And it is!

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Then a look at the finished surface

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A few minor bubbles on the surface but nothing I'm concerned about - this is the side that gets glued to the lid after all.

It's now in the airing cupboard overnight to cure hard enough to get out of the mould. And I have ordered another heated pet blanket off ebay so I can cover the whole of the boot lid next up and speed up the curing without having to use a 'faster' hardener for the epoxy resin.

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That all looks really ace. I congratulate you A. For trying it and B. For your well deserved success. 
 

always impressed with the high standards of engineering ability on here. Which is why I tend to lurk. 
 

this week end I fitted a couple of led warning lights - :blush:

well done I’m impressed. 
H

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21 minutes ago, Escadrille Ecosse said:

It's basking in the airing cupboard

:huh: you can put stinky composites in the airing cupboard without evisceration?

Impressive..... SM is pretty tolerant but I know what my life is worth......:ninja:

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46 minutes ago, Nick Jones said:

:huh: you can put stinky composites in the airing cupboard without evisceration?

Impressive..... SM is pretty tolerant but I know what my life is worth......:ninja:

Ha ha I thought that too

I've not dared use the dishwasher for car parts yet !!

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5 hours ago, Nick Jones said:

:huh: you can put stinky composites in the airing cupboard without evisceration?

Impressive..... SM is pretty tolerant but I know what my life is worth......:ninja:

That's a very fair point to be honest. I think the only reason I got away with it this time is that the epoxy has a very low odour itself and had sealed in any smell from the polyester gelcoat. It also got put on the 'dirty' side of the airing cupboard where herself dries her manky trail running shoes and other kit.

5 hours ago, Hamish said:

I've not dared use the dishwasher for car parts yet !!

Only once when I had the house to myself for a few days. Barely got away with that.

The other one of course is the using the oven to warm things up, like cylinder heads to install new valve guides. :ninja:

Anyway another 12 hours at basking temperature did the trick and fully cured the part. Now out of the mould

20210330_105532.thumb.jpg.ce0725acdb474ff1be2f101266a53240.jpg

It is incredibly light! Even before most of what's there gets cut off!!

Although to be fair that was only 3 layers of 200 g/m2 cloth and most of the other panels will be double that and/or have a core to increase the depth of section.

The other thing is I'm used to hand laid polyester/glass which for the same weight/m2 of reinforcement would be two - three times the thickness and weight!

Also a little bit of print through of the weave visible in the gelcoat but that was kind of expected as ideally you'd spray the gel rather than brush like I'm doing. As I'm not going for a cosmetic carbon fibre finish and everything will be painted it doesn't really matter. But I'll see if I can go better for next time :biggrin:

And for the first part it's all about learning the tricks and quirks of the process.

Next up is the boot lid itself.

I've also been thinking about the door shells. Original plan had been to reuse the existing shells and reskin in CF. But then decided that it would be simpler just to make new ones from my existing moulds again - using polyester/glass. However having done this first CF part I've finally decided to go for the same for the door shells and have ordered the materials. The moulds will need a bit of work to make them suitable but I think it should turn out OK.

I dug out the door shell moulds to have a look. Not bad nick on the whole. They were taken from a couple of good MkIV doors with the unnecessary holes filled in for use on my Mk2 with the later style door latches (and also a plan I had to fit GT6 quarterlights) so I have the lock mounting boxes to make too. But they need to be made separately and then fitted after because of the hole arrangement for the latch in the rear edge of the door.

20210329_105733.thumb.jpg.839243cc8622d3ce00c7b87aca008431.jpg

 

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Oh, and the modded spacers for the front hubs came back from James with a 45 degree relief on the inside bore at the small end. Should be no issues with that. Good chap that he is.

Put to one side for now while the car is up on the hoist out of the way and I get on with the sticky stuff.

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6 hours ago, Escadrille Ecosse said:

20210330_105532.thumb.jpg.ce0725acdb474ff1be2f101266a53240.jpg

It is incredibly light! Even before most of what's there gets cut off!!

That looks very impressive. Carbon fibre doors ... that will be ace! Has anyone else done this for a Spitfire that you're aware of?

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I never believed that carbon fibre was doable, without a vacuum source and an autoclave!   So I built Silverback's dors from GRP, from two moulds for each door, made as for the metal version but from the OE part , glued together with resin.      I went for as lightweight as possible, and the  result, with hinges and locks in place, but no glass (that was polycarbonate and hung from the A post, not mounted on the door) weighed only 5kgs each door.

586773784_nakeddoor.jpg.bef0b1b791dab96194d379febb117f31.jpg

This is a door, without any hardware.   The holes are for access to the hinge bolts, and for a wire pull-cord for the door lock release.

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There were some composite Spitfire doors made by a German guy 10+years ago. Dave Powell had a pair on his Spitfire and iirc a couple of others on the forum at the time had them too. I think he (the German guy) hoped to sell lots of them, but they were quite pricey in the context of “another fibreglass Spitfire door”.  That is not what they were though. Not sure carbon was involved, but foam certainly was. They were very light, very strong, superb finish and they fitted properly.

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11 hours ago, JohnD said:

I never believed that carbon fibre was doable, without a vacuum source and an autoclave!   So I built Silverback's dors from GRP, from two moulds for each door, made as for the metal version but from the OE part , glued together with resin.      I went for as lightweight as possible, and the  result, with hinges and locks in place, but no glass (that was polycarbonate and hung from the A post, not mounted on the door) weighed only 5kgs each door.

586773784_nakeddoor.jpg.bef0b1b791dab96194d379febb117f31.jpg

This is a door, without any hardware.   The holes are for access to the hinge bolts, and for a wire pull-cord for the door lock release.

Pretty much how mine are made John. GRP door skin glued to the GRP shell.

This will be the third set of composite doors I've made. First set for the 6 cylinder car were built fairly robustly (lasted almost 40 years) with glass wind up windows etc, and a length of roll cage tubing welded between the brackets holding the hinges and door locks. These were about 4-5 kg lighter than standard fully fitted up.

The lightweight 'race' set for the Mk1 were built super light. Shell and skin as John's without any hardware just under 1kg :laugh:

Strong enough to keep most of the draught out but quite flexy.... to say the least.

Polycarbonate windows but everything else on the door was standard. So I kept the original locks and lock operating mechanism and lever, hinges, handles and I also fitted standard door trims. The trims are probably the heaviest part of the whole door! :blink:

Even so the race doors fully fitted up and including hinges and the door trims are only 5kg each.

The aim with the carbon fibre doors is for around 4kg without any hardware each but at least as stiff as the steel doors.

36 minutes ago, Nick Jones said:

There were some composite Spitfire doors made by a German guy 10+years ago. Dave Powell had a pair on his Spitfire and iirc a couple of others on the forum at the time had them too. I think he (the German guy) hoped to sell lots of them, but they were quite pricey in the context of “another fibreglass Spitfire door”.  That is not what they were though. Not sure carbon was involved, but foam certainly was. They were very light, very strong, superb finish and they fitted properly.

This is the problem Nick. There is a company called Arc Angels that make high quality glass and carbon fibre panels for Minis (the real ones) and the prices while very reasonable I think are well above cheap and cheerful.

https://www.the-arc-angels.co.uk/shop/index.php?route=product/product&product_id=146

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There's astounding variation!  Some CF parts are £20, others, not very different £200++.  No idea why, except quality?

 

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3 hours ago, JohnD said:

There's astounding variation!  Some CF parts are £20, others, not very different £200++.  No idea why, except quality?

 

In terms of cost of manufacture I suspect it's probably mainly down to volume and quality. Carbon stuff is always going to have a significant manual element but for high volumes then production tooling, pre-pregs and autoclave make it much more efficient than hand layup and vac-infusion.

Quality wise a lot of the really cheap carbon you see isn't actually carbon as you think of it. At best it will have a carbon cosmetic layer laminated with polyester to glass or similar and at worst it's just a fake finish.

Price wise, it's what the chancer, sorry seller, thinks they can get away with on ebay :pirate:

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Once more into the breach. Boot lid this time. I actually started last week but had a bit of a disaster when the roller I was using to apply the gelcoat started to shed all it's fluff. So that was that knackered.

Recovery was a bit of a pain. There was insufficient time to remove it all from the mould before it cured so the only way out was to let it cure and then add a layer of glassfibre to get it strong enough to remove without disintegrating. That done and removed the mould need prepped again.

So yesterday I got some new rollers and with the mould all sorted applied the gelcoat and today I have been building up the panel. A bit more complicated than the first bit I did.

A layer of 200g twill cloth

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Then some 2mm thick cellular core. The cutouts are for the additional reinforcement around the hinge locations.

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To avoid a big step between the edge of the core and the rest of the panel I added three layers of 200g tape round the edge.

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At the hinges there is three layers of 200g cloth in the depression and another three layers extending roughly 30mm all round

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All held in place with the spray tack adhesive while I get it assembled.

On top of that lot I put a single layer of 650g carbon twill cloth, which I didn't photograph. The nylon peel ply on top of all that and starting to place the infusion mesh and the resin and vac connections.

20210407_181459.thumb.jpg.93d222ab044cb797601749fa4aae05d9.jpg

That lot has taken most of the afternoon and now in making my tea!

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52 minutes ago, Escadrille Ecosse said:

That lot has taken most of the afternoon and now in making my tea!

Well earned tea, and thawing out no doubt.:coldb:

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