+x Dentex - 11/1/2020 12:32:48 AMHy 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
+x carbon man - 10/31/2020 1:27:02 PM+x K.C.C - 10/31/2020 7:47:43 AM+x carbon man - 10/31/2020 6:21:04 AM+x K.C.C - 12/26/2019 4:08:11 PMStarted 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 postcuringI'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.
+x K.C.C - 10/31/2020 7:47:43 AM+x carbon man - 10/31/2020 6:21:04 AM+x K.C.C - 12/26/2019 4:08:11 PMStarted 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 postcuringI'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
+x carbon man - 10/31/2020 6:21:04 AM+x K.C.C - 12/26/2019 4:08:11 PMStarted 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
+x K.C.C - 12/26/2019 4:08:11 PMStarted 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
+x benji82 - 10/31/2020 11:30:10 AMGood 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.
+x benji82 - 10/31/2020 10:50:28 AMNice! 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.