Uni-Mould What I did wrong?

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Uni-Mould What I did wrong?

Author	Message
Olivier	Olivier posted 10 Years Ago HOT Topic Details
Group: Forum Members Posts: 26, Visits: 89	Hello everybody, I am making cf wrist protections for roller or snowboard. I decided to make a print of my hands with plaster bands (ones used in hospitals to repair broken bones). Then I reinforced them with EC Pattern Coat Primer and Hi Gloss (also some car body filler) It was my first attempt to use those products and it was great to do it. Then I used those glossy hand prints to make a mould with EC Uni-Mould. Maybe here is where I made a mistake - do not know I made a positive mould from the imprints and it released perfectly. Then I made a negative mould of the uni-mould mould. I used 5 coats of easy lease release agent and a coat of wax. I used filleting wax to build edges where I was not sure moulds will release. And I started with the gel coat, coupling and tooling uni-mould. After a week I decided to post cure the moulds up to 80 °C as noted on uni-mould pdf. Then I decided to separate the moulds and it was very very difficult. I succeeded without to much damages to the moulds (at least the area I need to make the final parts) I will repair the mould later but I would like to know what I did wrong and was the right way to do it. Thanks for your help guys
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Could be a heap of things. Could you post photos?
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Olivier	Olivier posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 26, Visits: 89	Hi, Sorry for the delay I was away for my job. So here are the pictures: - first imprints reinforced with Pattern Coat Primer and Hi Gloss - First stage positive mould with Uni-mould - Second Stage negative mould with Uni-mould (not cleaned) I had issue releasing the second stage only. Should it be a better idea to make an epoxy mould from the first imprints? Attachments image.jpg (468 views, 899.00 KB) image.jpg (601 views, 957.00 KB) image.jpg (577 views, 501.00 KB) image.jpg (603 views, 623.00 KB)
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	It should work fine, I'm a bit surprised you had issues. Even your flanges look like they stuck, what did you use to make them? How did you apply the Easylease? Did you clean the first moulds well before applying the release agent? If you had residue from wax, it's possible that comprised the release agent, though I'd be a bit surprised if that was the case as you can usually get away with that.
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Matthieu Libeert	Matthieu Libeert posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 955, Visits: 3.4K	As far as I'm reading your description, you made the mould and then postcured your mould to 80°C? did you ramp up in temperatures over multiple hours? Then you demoulded the part from the mould? Might be possible you had to postcure your part first before making the mould and postcure the part still in the mould. Might be possible you "cured" your part in the mould and a chemical bond started between your part and the mould. Other than that, your mould seems ok to repair Matthieu Libeert Founder MAT2 Composites X Sports website: www.mat2composites.com
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Well he got the stick on the second mould, so both the pattern and the mould were made from unimould. So there shouldn't have been any chemical reactions. I'm sure it must have been a release failure, though I'm not sure why.
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Olivier	Olivier posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 26, Visits: 89	Hi Hanaldo, Matt, I do not think the flanges stuck but are damaged by tools I had to use to separate both moulds. Flanges made with EC Fluted signboard. 6 coats of easylease buffed. Mould cleaned with EC mould cleaner. I do not understand why it stuck. I never had issues with any of my Unimould jobs before. Thanks for your help
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Hanaldo	Hanaldo posted 10 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Ah, 2 potential issues there. First of all, when you say cleaned with mould cleaner, was that after applying the release agent? That would strip the release agent right off again. Second, you shouldn't buff the surface after applying a chemical release agent, you can actually remove it again. Why are you buffing it?
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