Resin issues in sun light

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Resin issues in sun light

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BMac	B BMac posted 5 Years Ago HOT Topic Details
B Group: Forum Members Posts: 16, Visits: 63	I recently used your carbon fibre skinning kit on a car product. I measured the resin to exactly 3:1 ratio in good conditions at the start of summer. The resin cured fine and I got it to a great finish. However 4 days after installing the product in the outside of the car the direct sunlight has caused the resin to form ripples in line with the carbon fibre. They are all equal straight lines. The resin has developed a greyish tone to it. Can you explain why this has happened. I am working on two other car parts and I'm afraid to out them on the car in case the same thing happens. Thanks B
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Lester Populaire	L Lester Populaire posted 5 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x BMac - 7/6/2020 9:43:59 PM I recently used your carbon fibre skinning kit on a car product. I measured the resin to exactly 3:1 ratio in good conditions at the start of summer. The resin cured fine and I got it to a great finish. However 4 days after installing the product in the outside of the car the direct sunlight has caused the resin to form ripples in line with the carbon fibre. They are all equal straight lines. The resin has developed a greyish tone to it. Can you explain why this has happened. I am working on two other car parts and I'm afraid to out them on the car in case the same thing happens. Thanks B You really need to post cure car parts before exposing them to heat. And to have a lasting part you need to paint them too. With a hand laminating resin where the glass transition temperature is not going to be higher than 80°C typically I'm not even sure you can get a lasting finish at all. Typically i try to stay 20°C under the Tg during use. The clear coat is needed for uv resistance. Hope this helps Cheers!
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BMac	B BMac posted 5 Years Ago HOT Post Details
B Group: Forum Members Posts: 16, Visits: 63	+x Lester Populaire - 7/7/2020 7:20:56 AM +x BMac - 7/6/2020 9:43:59 PM I recently used your carbon fibre skinning kit on a car product. I measured the resin to exactly 3:1 ratio in good conditions at the start of summer. The resin cured fine and I got it to a great finish. However 4 days after installing the product in the outside of the car the direct sunlight has caused the resin to form ripples in line with the carbon fibre. They are all equal straight lines. The resin has developed a greyish tone to it. Can you explain why this has happened. I am working on two other car parts and I'm afraid to out them on the car in case the same thing happens. Thanks B You really need to post cure car parts before exposing them to heat. And to have a lasting part you need to paint them too. With a hand laminating resin where the glass transition temperature is not going to be higher than 80°C typically I'm not even sure you can get a lasting finish at all. Typically i try to stay 20°C under the Tg during use. The clear coat is needed for uv resistance. Hope this helps Cheers! Thanks for the reply. I let the part post cure for 1 week before sanding and polishing. Then 4 days before putting it on a car. I am using the XCR Resin which should surely be able to handle summer sun in the UK. Max temp here in NI was 24C I am hesitant to spray paint the product because using acrylic lacquer is a waste of time and 10x worse at rippling in the sun than the current finish. I know cause i tried it before and when i used a hair dryer on the paint it was horrible. So that leaves 2K hard lacquer. Is 2k Lacquer compatible with this resin though? Again i have used 2K on parts before whereby if the undercoat is not compatible you end up with a spider web effect which is very messy.
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