Hi, I want to make 2 front wings in carbon for my 106 Maxi and I have the original items to make a mould from.

I have no doubt if I had all the stuff in front of me I could make a panel I would be happy with but I get

totally lost when I try to figure out what exactly I need to make a mould and what I need to make the carbon

panel and how much of everything is required.

I am not looking for a smooth show finish as the panels will be painted and covered in sign wrighting so

do I need to vacuum bag them of is there another way around it.

Thanks in advance for your help.

you don't need to vacuum bag them but its the resin that has the weight!

Hi Dave,

OK, I should be able to give you a complete enough shopping list for your project. What you don't mention (as Neil has alluded to) is whether weight is a priority. Whilst my suggestion (and so shopping list) for the mould making materials would be pretty much the same no matter how you intend to make the finished parts, there are around about 3 different levels you could tackle the actual parts at:

(Level 1)
You just make them out of GRP using polyester gelcoat and polyester resin reinforced with CSM or woven roving.
Cost = 1/10
Difficulty = 3/10
Result = Heaviest

(Level 2)
Resin infuse using epoxy resin but reinforced with bixial and woven glass fibre and possibly a core material.
Cost = 7/10
Difficulty = 7/10
Result = Significant weight saving over level 1

(Level 3)
Resin infused using epoxy resin and reinforced using carbon fibre and possibly a core material.
Cost = 9/10
Difficulty = 7/10
Result = Medium weight saving over level 2

Let me know where you want to pitch this project and I'll give you a good list to get you going.

--Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

Thanks for the quick reply gents,

Neil, are you saying there is less resin used when vac bagging? I guess that makes sence.

The genuine parts are Kevlar so I want to make either carbon of kevlar replacements.

I'm thinking 2 layers of carbon with 1 layer of kevlar in between? I'm looking for something

light but ditch friendly

Hi Dave,

OK, well, ditch-friedly means Kevlar or Diolen; carbon is not so ditch friendly. Kevlar is no cheaper than carbon really but it will certainly be more impact resiliant.

What colour are you panels going to be painted, is it something simple to match (like WHITE or BLACK) or is it a specific colour? - If it's black or white then the easier thing might be to simply use a pigmented gelcoat in the mould first and then you won't need to paint the panels afterwards.

To help you calculate the amount of material you would need to make the moulds it would be helpful to know the approximate surface area of the wings but I can have a decent guess that they would be around 1.5m x 0.8m = 1.2sqm. Allowing for some decent flange area around the mould we're talking 1.5sqm per side. This is handy because our Large Uni-Mould Mould Making Kit is based around making 3.3sqm of mould so would be ideal. This kit includes everything you would need to make the moulds except for release agent so I'd just suggest adding a 500ml bottle of Easy-Lease Chemical Release Agent and then a tin of Mould Release Wax.

That's your moulds taken care of so you're onto making the parts themselves. If you want to keep weight down then vacuuming (either vacuum bagging or resin infusion) will make a big difference. Yes, the weight can be in the resin, or at least the weight that can be eliminated is in the resin, the fibre does the work.

Resin infusion would give you the lightest panel and the best surface finish but it's also possible to have something go wrong with resin infusion if you're new to it and there's slightly more set-up cost (because of the catch-pot). If you wanted the parts to have a good surface finish then I'd tell you it MUST be resin infusion (because vac bagged parts won't ever have a showroom finish straight out of the mould) but as you'renot too worried about surface finish then vacuum bagging is an option for you. We're working on a new technique at the moment that's not quite ready for me to announce on this forum but what I can say is that if you just need to vacuum bag this then we should be able to set you up with everything you would need to do this for around £100. It's not a system that would be right for everyone but I think it would be right for you.

Finally then, your materials. I think your 3 layers of reinforcement would be too thin, the panels will be very flexible. For your impact resistant panels I would go for either:

3-4 layers of 300g kevlar (3 layers if you used some 3mm closed cell PVC foam in areas, 4 at least 4 layers if you didn't)

or/

1 layer of 300g kevlar
4 layers of 300g diolen
1 layer of 300g kevlar

You might also want to vac in some 3mm closed cell PVC foam inside the laminate on the flatter areas to improve the stiffness of the panel without adding much weight.

Use EL-2 Laminating Epoxy on a medium hardener speed (mix fast and slow together 50/50) to give yourself plenty of working time.

If you tell me what layup you want to go for and exactly what those panels measure I should be able to give you quantities on both the resin and the reinforcement.

--Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales

Great info there. I will order a Uni-mould kit in about 3 weeks when I am working in Carlisle (I am from Ireland)

that way I will be able to get the MEKP with the kit and save on some postage at the same time.

If my moulds turn out good I will then go ahead and order the Kevlar etc.

Just one more question, for a deep wide arch wing, will the vacuum bag be able to pull the carbon into all the corners

etc or is there a way I can stick all the kevlar in place before I bag? Also will the resin flow to all the corners?

sorry for the short first reply,

the resin will flow the easiest where ever the infusion mesh is, yes the vacuum will pull the cloth into the corners but you will have to ease it in while under a partial vacuum otherwise the cloth will 'bridge' across. it is possible to use a spray adhesive (i think matt now stocks this) and then glue your cloth into the mould, so you can position it well into the corners and along the edges (bonnet/door edges)

Hi Dave,

(Late) answer to those couple of questions you raised..

for a deep wide arch wing, will the vacuum bag be able to pull the carbon into all the cornersetc or is there a way I can stick all the kevlar in place before I bag?

The vacuum bag should never be relied on to pull the reinforcement into the corners - this is a recipe for bridging problems. Spray adhesives are the way to do it in this case, prior to bagging. This is an ongoing saga at the moment but contact me when you're ordering and I'll talk you through the latest news/best options.

Best regards, Matt

Matt Statham
Easy Composites / Carbon Mods - Technical Sales