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baja_patient
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Acetone is used to activate the gelcoat and make it sticky. I don't think you need much.
Between layers spray adhesive is used. Now they offer an epoxy based spray adhesive that fuses with the dominant resin system. In the video however, i think it is regular spray adhesive which can also be okay when used very sparingly.
cheers
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Matt (Staff)
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Hi Sawral,
On the movie you use GC50 Compatible Epoxy Polyester Gelcoat. What to use to activate it to stuck CF to the surface.
This is a complicated one and something that's haunted us a bit since we made that video. We shot the video over last Christmas with a 'prototype' version of the GC50. That version of GC50 did become tacky when a small amount of acetone was sprayed onto it and so we used this method to tack down the carbon to the gelcoat. Since then, we had to make some changes to the GC50 in order for it to stay receptive to resin for longer and when we made these changes, this bonus effect that the gelcoat became activated by acetone doesn't really exist anymore. The GC50 that we finalised and put on sale does not behave in this way.
Instead, to tack to the mould surface, whether there is gelcoat there or not, you will need to use an epoxy compatibel spray tack like the Zyvax product (which infortunately is not currently available) or by mixing up some epoxy resin with methylated spirit and spraying it onto the mould or gelcoat (as we've described many times before on this forum).
Then on the bottom of the bonnet to use another spray stuck CF perfectly to the surface. What is spreyyou useing?
This would be the Zyvax Stay-Z product, see above.
I hope this helps and sorry for any confusion we cuased with this. I'll add some captions to the video to make this clearer.
--Matt
Matt StathamEasy Composites / Carbon Mods - Technical Sales
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Sawrel
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Thank you very much for your reply. It is very helpful.
One more question:
At one topic on the forum I saw the equation to how many I needed epoxy Infusion Resin to comply with an object, but unfortunately I can not find it now. Can I ask to enter it in this thread.
Thank you very much.
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Matt (Staff)
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Follow this link to Paul's Resin Infusion Resin Usage Calculation.
Matt StathamEasy Composites / Carbon Mods - Technical Sales
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Sawrel
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Thanks Matt for your help, now I can go shopping 
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Sawrel
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mixing up some epoxy resin with methylated spirit and spraying it onto the mould
What proportion of epoxy resin to methylated spirit use to the mixture?
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Matt (Staff)
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About 10-20% methylated spirit added to epoxy infusion resin that has been mixed with the correct amount of infusion resin hardener already should be enough to thin the resin sufficiently that it will 'mist' through a trigger press spray bottle. It's not a exact science, just add a few drops at a time until you have a consistency that will spray.
Don't be tempted to use acetone, white spirit or turps. Methylated spirit (denatured alcohol) or 100% alcohol is needed for this.
Matt Statham
Easy Composites / Carbon Mods - Technical Sales
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Sawrel
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Thanks Matt. As always, helpful advice
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dei
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Hi, I need an advice on skinning an open container made with polyerster with a cut cover.
1.) What type of resin will be good with the polyester that a temperature of upto 100ºC and drop to 12ºC.
2.) Would the resin glue a ceramic material pamanetly?
3.) What do you recommend polyester or polystyrene for Carbon skinning
4.) Can I use Carbon fiber glass over normal fiber glass?
Thank in advance
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andygtt
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Hi Around the time this post started I decided to make carbon panels for my Noble sports car... I had NEVER worked with carbon before and had very limited experience of GF working, having never even made a mould before let alone body panels. What I did was use GF, filler and expanding foam to remould my body to the new shapes required... I then painted the panel (will call then bucks from now on). The bucks were heavy and pretty fragile so needed careful storage / handling often strengthening bars to allow the panel to take its own weight without distorting / breaking. I then used easycomposites UN1 tooling system, bloody excellent stuff this as it has zero shrinkage... you have to be careful with the gel coat to avoid wrinkling due to it not being mixed fully (easy to do) or it reacting with the Buck but otherwise its extremely easy to use. Due to the size and complexity of some of my panels I had to have multiple break lines (my rear end is a 12 piece mould), this needs to be well thought out but isn't hard just requires careful thought. I wanted areas of my panels painted and other areas with visable carbon... this is tricky but not overly hard... with care and attention you can get very nice lines even on complex parts, first make a paper template then cut this out of the pro finish carbon.... yes this takes practice but its not stupidly difficult. Getting the carbon to stay in place without voids is very tricky, Im still experimenting in this area but I used a spray tack which you MUST use sparingly otherwise you effectively glue your part to the mould and its very hard to remove... I had to use 3 crow bars to extract one part of my rear body... not for the faint hearted and a mistake not replicated quickly. As a beginner giving advice to potential beginners I would say the following. 1. Fully bag complex moulds... its difficult to get a full seal especially around multiple break lines. 2. DONT use a gel coat or 2 pack in the mould... this is because if the part goes wrong or has a leak its scrap as the pinhead air holes will be behind the gel coat... if its a raw carbon finish you can fill them with black epoxy filler and never notice them. Once your more skilled you can use this method for faster results. 3. Use tack spray sparingly. 4. take your time laying the first surface carbon layer to get the weave nice and no voids... voids here will be almost impossible to get rid of once further layers of carbon, soric and the peal ply is added. 5. Dont rush I have a thread on some of the parts I have made... but here are a few highlights to show what an accountant with zero composites experience can do using the easycomposites materials and advice  The rear clip was only the second mould/part I ever made in carbon, and the first was a disaster lol |
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