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K.C.C
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Group: Forum Members
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+xNice! I guess you know that these simple looking parts can be a pain in the backside when it comes to mounting points and clips! Sometimes this is quite difficult to get across to a customer. Ppl really dont know how much work there is in one complete fairing set and the prices are way to low for the work actually . But I love doing it I make arround 30 sets a year but 10 for myself 
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K.C.C
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Group: Forum Members
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benji82
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Group: Forum Members
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Good work!
Are you using Nord vinylester? I'm going to experiment with Uni-mould and see if I can get some reasonable prepreg parts out of them.
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K.C.C
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Group: Forum Members
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+xGood work! Are you using Nord vinylester? I'm going to experiment with Uni-mould and see if I can get some reasonable prepreg parts out of them. That I dont know, I'm using these mould making resins for over 10 years now from the same company, they look verry simular to the unimould resins. You can get good prepreg parts out of them. I only make the EL160 moulds because I dont want to use easylease release agent on my moulds that I use for glassfibre parts. Not because Easy lease is bad but because its to good I noticed having some prerelease and also fisheyes in the normal gelcoat when using easylease. When I waited longer after the last coat of easylease this got better but I cant wait that long so thats why I'm making the EL160 moulds.
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carbon man
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Group: Awaiting Activation
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+x+x+xStarted with some smaler moulds again today . ad some small high temp epoxy moulds made before and they had no problem and I remember I only used 1 layer gelcoat How are you getting on now? I hate this system! So many delamination and cracks. I literally can't make moulds using 2 layers of gel or it will crack, chip and delaminat iv tried applying the 2nd layer of gel with every different stage of tack. Now I make just using 1 layer of gel. Moulds are better but still after 6 pulls I got a hair line crack. All my moulds are small like 8 inch. I fear if I make a large moulds it will just break! And I'm having to make them really thick using several layers 650g carbon for backing. Let me know if you have a solution. Thanks I kept working with 1 layer gel but I do wait 4 to 5 days before demoulding and atleast 7 days before postcuring I'm now testing 2 layers of gel again reducing the time between the layers and at first sight this looks good . Problem also is that when you work with parts that have verry small edges that need to be trim off you need to look out not putting the gel to thin on there Differend thickness of gell, difference in curing. I use first 2 layers of 200G twill 2X2 let this gell up for some time than I add 2 layers 400G twill 2X2 ending with last layer of 200G twill 2X2. And than let it cure for 4 to 5 days. I finished 2 new moulds this week with 2 layers gel , wil keep you posted the results Yes please do. How long are you leaving the 1st 2 layers to gel up? When I tried this it de laminated after post cure. And I applied the 2nd lot of carbon once the first lot was going off but still tacky.
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K.C.C
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Group: Forum Members
Posts: 54,
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+x+x+x+xStarted with some smaler moulds again today . ad some small high temp epoxy moulds made before and they had no problem and I remember I only used 1 layer gelcoat How are you getting on now? I hate this system! So many delamination and cracks. I literally can't make moulds using 2 layers of gel or it will crack, chip and delaminat iv tried applying the 2nd layer of gel with every different stage of tack. Now I make just using 1 layer of gel. Moulds are better but still after 6 pulls I got a hair line crack. All my moulds are small like 8 inch. I fear if I make a large moulds it will just break! And I'm having to make them really thick using several layers 650g carbon for backing. Let me know if you have a solution. Thanks I kept working with 1 layer gel but I do wait 4 to 5 days before demoulding and atleast 7 days before postcuring I'm now testing 2 layers of gel again reducing the time between the layers and at first sight this looks good . Problem also is that when you work with parts that have verry small edges that need to be trim off you need to look out not putting the gel to thin on there Differend thickness of gell, difference in curing. I use first 2 layers of 200G twill 2X2 let this gell up for some time than I add 2 layers 400G twill 2X2 ending with last layer of 200G twill 2X2. And than let it cure for 4 to 5 days. I finished 2 new moulds this week with 2 layers gel , wil keep you posted the results Yes please do. How long are you leaving the 1st 2 layers to gel up? When I tried this it de laminated after post cure. And I applied the 2nd lot of carbon once the first lot was going off but still tacky. The gelcoats I wait 1u30min max at a room temp of arround 20°C the laminating also arround 1u30min you can wait longer but as soon as I see I cant move the first layers anymore Problem with epoxy resin is it got a verry low viscosity and when making complex parts with lots of sharp corners high spots etc. You got a perfect layup no air or dry spots, you come look 1H later and all the high spots are full of dry spots where the resin just had run down. Therefore the 280g 2x2 Twill Woven Glass Cloth from easycomposites is perfect for first 2 layers. It works so easy and keeps the resin on high spots when used correct, not to much resin or you get floating. When you only use carbon fibre you wont see the air or dryspots especially on complex parts Therefore I think you better could use first layers of 280g 2x2 Twill Woven Glass Cloth and when this is gelled just right you can back it up with carbon fibre.
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Dentex
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Group: Forum Members
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Hy KCC, Thanks for all these informations. I plan on making mould with eg160 gelcoat and el160 laminating resin so all of this is very useful. As I can understand, you wait approx. 1:30h between gelcoat layers at 20°C and have no delamination issues when mould is cured for couple of days at room temp? How long to wait between every layer of fabric? I will use only 200g twill carbon so I need around 10-12 layers for each mould part. Only part I don't agree with is not using only carbon for high temp pre preg moulds. For some that would be ok, but in my case that could result in around 1.5mm differences due to different expansion rates when heated. With my part that could result in useless product. I don't have actual experience and talking just from calculations but better safe than sorry
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K.C.C
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Group: Forum Members
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+xHy KCC, Thanks for all these informations. I plan on making mould with eg160 gelcoat and el160 laminating resin so all of this is very useful. As I can understand, you wait approx. 1:30h between gelcoat layers at 20°C and have no delamination issues when mould is cured for couple of days at room temp? How long to wait between every layer of fabric? I will use only 200g twill carbon so I need around 10-12 layers for each mould part. Only part I don't agree with is not using only carbon for high temp pre preg moulds. For some that would be ok, but in my case that could result in around 1.5mm differences due to different expansion rates when heated. With my part that could result in useless product. I don't have actual experience and talking just from calculations but better safe than sorry Technecal data sheet EG160: The second gelcoat layer as well as main reinforcement application must be made whilst the previous gelcoat application is still in its ‘b-stage’ which means that it is firm but still tacky. The gelcoat must not be allowed to cure past this point without the next layer having been added otherwise delamination (especially at elevated temperature) is likely The time I wait is 1u30min between layers also for putting backing layers I would stil put up atleast the first layer of backing in 280G twill glass as a "cuppling" coat than atleast you wil be sure you wont have air voids there. and than backup with carbon fibre I think the expansion wont be that much different with only 1 layer glass.
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Dentex
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Group: Forum Members
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If I understood you right, you were saying that if fiberglass is used as first layer, you are able to see lifted and dry fabric before adding second layer? I guess you push those parts back when resin gets more tacky with brush or roller and proceed with layup?
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K.C.C
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Group: Forum Members
Posts: 54,
Visits: 117
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+xIf I understood you right, you were saying that if fiberglass is used as first layer, you are able to see lifted and dry fabric before adding second layer? I guess you push those parts back when resin gets more tacky with brush or roller and proceed with layup? Not completely the difference is that you can see air when working with fibreglass and so you can make sure you dont got air trapped or dry spots, I stay in the room all the time until its gelled and sometimes yes I put some resin on the dry spots as the resin can stil flow down its still not gelled so you can slowly work it back up from under to above or use some resin if you got some left . As soon its gelled so it wont run down anymore I put the next layers. And I think thats stil the hardest problem laminating carbon parts you cant see air under the fabric if so why would we invest in vacuum, infusion and prepreg 
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