First mould attempt

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First mould attempt

Author	Message
Jaydien	Jaydien posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 8, Visits: 30	Also, just so you know, I've yet to make a single mould I would consider useable. I've made 5 so far and totally agree with carboncactus. You definitely are not gonna get it right the first bunch of times.
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Jaydien	Jaydien posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 8, Visits: 30	I'm a still at noob at this, so take everything I say with a grain of salt. I saw this first tip on YouTube. Get some woven roving and extract one thread of the weave. Use that thread on the hard angles BEFORE you lay anything else. I think I also saw that guy just use clumps of individual fiberglass strands on top of the tacky gel coat and soaked it with resin. I might be wrong about that, though. My personal THEORY is to lay the chopped strand mat in small sections. I've started two moulds like this so far. They are the unseen "bottom" sides of interior car panels which are extremly complex and have MANY right angles. I've only done one layer so far and my technique needs MUCH refining, but I think it could be a very promising course of action. It's a pain in the ass and is extremely time consuming. You need to measure, measure, measure. Everything must be cut before you start anything else. I hope this isn't against the forum rules, but the YouTube video is by gasserglass, I believe. Their not well edited at all and very long. I would actually have to call it "unedited". They are very boring as it's basically just a dude going about his fiberglassing and talking story (i think you Brits call that jawing) like you're a dude just hanging out at his shop with him. However, you do pick up a good tip every now and then.
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jonnyl888	jonnyl888 posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 6, Visits: 16	Yea, I might end up binning it. I was looking at the fibreglass putty, which would make life so much easier. Do you think it's worth giving this a try? Will it work out more expensive or similar?
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carboncactus	carboncactus posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 243, Visits: 1K	I had a similar issue when making a wing mould, the CSM didn't get into the corners, even though I bent it before applying then pushed it in. When I released, the mould looked impeccable..... Until I postured it in the oven and blisters started popping up. Then I took a screwdriver and tapped the corners an it revealed just how much air was in the mould: After speaking to some people, they suggested mixing the gelcoat with some silica and milled glass to make a paste, then spreading this paste into the corners to give it more of a radius, then laying the CSM on top of that. After doing this for a few months, I'm convinced you can't get a mould right the first time, or the first 10 times for that matter. Theres too many variables, and something WILL go wrong. It also doesn't help that when you're looking for help, different people give you different and often contradicting advice. As for your mold, start over. Repair work is a different art altogether. Repairing a mould with that much damage will take you much longer than binning it and starting over. Also, the repair work will be weaker and will inevitably cause issues down the line.
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jonnyl888	jonnyl888 posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 6, Visits: 16	Hi, just attempted making my first mould of a spoiler. So I pretty much followed the how to make a carbon bonnet video tutorials but one thing I didn't have was filleting wax. I used signboard all the way round and the inevitable happened. The gel coat seeped through under the part. What's worse was that it was difficult to get the chopped strand mat to stick into the edges without creating an air void which weakened the gel coat at the edges. As you see in the picture below, I got the basic shape and very nice shiny surface even with PVA, but the "mechanical lock" caused by the gel coat made me impatient and I ended up forcing the part out and cracking the edges around it. I really don't want this to go to waste, so is it worth repairing? Can I use fibreglass car body filler to do the job? Or is this a better way? Thanks Edited 12 Years Ago by jonnyl888
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