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K.C.C
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Group: Forum Members
Posts: 54,
Visits: 117
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Hello, I have been working many years with the unimould system but now I going over to the High Temp mould system for the xpreg prepregs .
I am laminating the mould with 1 layer 100G woven glass than 1 layer 280G woven glass after this I let it set to gell
han I put 2 layers of 400G woven glass and stop with 1 layer 100G glass to finish.
Are this enough layers for the moulds ?
And also "why I dont like epoxy " is there a way to not get the air coming up to the high spots in the moulds .
I make superbike fairings and they got alot of shard , round edges and when the glass and epoxy is just layed down , I dont got any airbubbles but after time the wil show up at high spots .
This is why I first put the 100G and 280G and leave them to gell first .
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K.C.C
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Group: Forum Members
Posts: 54,
Visits: 117
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Started 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
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Shaneer22
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Group: Forum Members
Posts: 156,
Visits: 14K
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+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 May try 1 layer gel coat then.i no when I have been trimming mold flanges with disc cutter gel coat has separated from second layer as if it has not bonded and Ian 100 percent it's not my lay up.
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K.C.C
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Group: Forum Members
Posts: 54,
Visits: 117
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+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 May try 1 layer gel coat then.i no when I have been trimming mold flanges with disc cutter gel coat has separated from second layer as if it has not bonded and Ian 100 percent it's not my lay up. Same here thing when you trim moulds to part size you better use 1 layer to be sure . What parts do you make ?
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Shaneer22
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Group: Forum Members
Posts: 156,
Visits: 14K
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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 May try 1 layer gel coat then.i no when I have been trimming mold flanges with disc cutter gel coat has separated from second layer as if it has not bonded and Ian 100 percent it's not my lay up. Same here thing when you trim moulds to part size you better use 1 layer to be sure . What parts do you make ?  
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Shaneer22
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Group: Forum Members
Posts: 156,
Visits: 14K
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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 May try 1 layer gel coat then.i no when I have been trimming mold flanges with disc cutter gel coat has separated from second layer as if it has not bonded and Ian 100 percent it's not my lay up. Same here thing when you trim moulds to part size you better use 1 layer to be sure . What parts do you make ? Fairing for my bike.
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Shaneer22
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Group: Forum Members
Posts: 156,
Visits: 14K
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+x+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 May try 1 layer gel coat then.i no when I have been trimming mold flanges with disc cutter gel coat has separated from second layer as if it has not bonded and Ian 100 percent it's not my lay up. Same here thing when you trim moulds to part size you better use 1 layer to be sure . What parts do you make ? Fairing for my bike. Just demolded tooling. 
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carbon man
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Group: Awaiting Activation
Posts: 86,
Visits: 1.2K
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+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
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K.C.C
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Group: Forum Members
Posts: 54,
Visits: 117
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+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
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carbon man
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Group: Awaiting Activation
Posts: 86,
Visits: 1.2K
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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,
Visits: 117
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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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