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Old 10-31-2015, 10:16 PM   #1

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Default Release Agent advice for Clay/MDF mould

Hey guys

Making a mould of my spoiler to make in carbon. Still a complete newbie to this, and (as you can probably tell) it's my first time using clay.

I've sprayed a few layers of acrylic clear, I'll need to use a release agent. My concern is that the clay is too soft to apply enough pressure when using paste wax. I could use PVA, but will this be efficient enough on its own? I've semi sealed the MDF, will PVA be fine with this?

Any advice or tips is definitely appreciated.

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Old 11-01-2015, 05:33 AM   #2

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If you're using a single pack acrylic then you will need to use PVA anyway. PVA works perfectly on its own if you can spray it. Spray it on in a few coats to get a decent film applied, and there's no need for wax or anything else.
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Old 11-02-2015, 07:05 PM   #3

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I've used the clay with PVA as Hanaldo explains, this works fine. You don't get the perfect gloss finish, but the clay parts should be beyond eop anyway.

Though it's easier if you release the MDF first, then clay it up, then PVA. As you said, they clay deforms pretty easily.
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Old 11-03-2015, 04:16 PM   #4

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I screwed this up the moment I put on a coat of epoxy. I was too lazy/impatient to make up a gelcoat. Epoxy pooled and covered terribly. Lesson learned.

MDF could have been sealed better, I think that's going to be a bitch to remove. I did 4-5 layers of 268 double bias (had no powder csm), and a layer of 450double bias. I still need to glass the sides, ran out of daylight.

I'll glass the rest tonight and release tomorrow night. I'm counting it as a failure already, but we'll see how well it went anyways.

As soft as clay is, I found it easily enough to wax it without breaking the acrylic skin. When you poke it with your finger though, it's like poking through a thin chocolate egg. Not as big of a deal as I thought it'd be.

A lot of corners were cut in the end, and I'm paying for it. So, back to square one, learn from it and go again 👍🏿
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advice, agent, clay or mdf, mould, release

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