What To Skim A Mould With?

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What To Skim A Mould With?

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dilligaf76	dilligaf76 posted 5 Years Ago HOT Topic Details
Group: Forum Members Posts: 49, Visits: 115	Can anyone tell me what’s the best thing to skim my mould with. It’s made from epoxy resin and fibre glass but as I never used a gel coat for various reasons it needs a final layer that I can sand and polish to a mirror finish. I could use normal epoxy resin but that’s going to be a task and a half to sand smooth. Someone in previous post of mine that I could use pattern coat primer but that’s apparently polyester and won’t bond to well to my mould. I’m a little stuck with the best thing to use, it’s obviously needs to be durable yet preferably easy to sand smooth, help please?
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Duratec surface primer and hi-gloss clear are made for resurfacing moulds, so they would be your best bet. But in all honestly man, speaking from 10 years of experience - nothing will work like you want it to. Resurfacing a mould is not an easy thing, especially when you have tight recesses like you do. Perhaps your one mould would be ok, the flatter one. But the other one with the deep 'canopy' section, you will never get an even coating on that and if you get a run or a sag or a brush stroke or anything like that then it becomes a physical lock. Given you used rattle cans to paint the moulds, I'm assuming you don't have proper spray equipment to apply any coatings well either? So you are really fighting a losing battle here. Your best solution is to remake the moulds. You will waste less time and money just starting again. if you don't have the original part you used to make the moulds, then use your current moulds to make a fresh male copy that you can then paint and sand and rework nicely. You will need to find a way to spray PVA release agent in order for that to work though, I would suggest a Preval sprayer if you want something cheap and easy.
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dilligaf76	dilligaf76 posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 49, Visits: 115	+x Hanaldo - 6/29/2020 10:26:21 PM Duratec surface primer and hi-gloss clear are made for resurfacing moulds, so they would be your best bet. But in all honestly man, speaking from 10 years of experience - nothing will work like you want it to. Resurfacing a mould is not an easy thing, especially when you have tight recesses like you do. Perhaps your one mould would be ok, the flatter one. But the other one with the deep 'canopy' section, you will never get an even coating on that and if you get a run or a sag or a brush stroke or anything like that then it becomes a physical lock. Given you used rattle cans to paint the moulds, I'm assuming you don't have proper spray equipment to apply any coatings well either? So you are really fighting a losing battle here. Your best solution is to remake the moulds. You will waste less time and money just starting again. if you don't have the original part you used to make the moulds, then use your current moulds to make a fresh male copy that you can then paint and sand and rework nicely. You will need to find a way to spray PVA release agent in order for that to work though, I would suggest a Preval sprayer if you want something cheap and easy. Hello Hanaldo and thanks for your input. Interesting you mention about the mould with the tight recess because today I was pondering on whether to cut it long ways down the middle and have as two parts that I can then bolt together when needed. I found that with the c*** up I made what with the paint and that, that the bagging did prove to be difficult along the recessed section and releasing the part was also a bit tricky. It might mean joining the two pulled parts together after depending on how I do it but that's not a problem. The only problem I might come across is if I lay the cloth and resin in a split mould bolted together what would be the best was to temporally block that seam, filleting wax?? I'm not sure about remaking the whole lot but I definitely can see where you are coming from. Oh are those Preval sprayer any good? One other thing, are you on facebook? don't worry I'm not some stalker and of course you don't have to accept but its nice to occasionally chat and be friends with someone that has a common interest. Regards Craig.
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	A split mould isn't a terrible idea, but it shouldn't be necessary. Also has to be done properly, you can't just cut the mould in half. You need a flange there on each side of the mould that allows you to bolt the two halves together. This is all done when you make the mould, so it's something to think about when you reach the inevitable conclusion that starting again is the quickest and best solution. Preval sprayers are ok, they're about as good as a rattle can. But you can spray just about anything with them, so they are more versatile than rattle cans. They're a good option if a proper compressor and spray equipment is out of the question. I have got a personal Facebook page, I only have a business page. Unzipped Composites.
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dilligaf76	dilligaf76 posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 49, Visits: 115	+x Hanaldo - 6/30/2020 4:25:03 AM A split mould isn't a terrible idea, but it shouldn't be necessary. Also has to be done properly, you can't just cut the mould in half. You need a flange there on each side of the mould that allows you to bolt the two halves together. This is all done when you make the mould, so it's something to think about when you reach the inevitable conclusion that starting again is the quickest and best solution. Preval sprayers are ok, they're about as good as a rattle can. But you can spray just about anything with them, so they are more versatile than rattle cans. They're a good option if a proper compressor and spray equipment is out of the question. I have got a personal Facebook page, I only have a business page. Unzipped Composites. Hello m8, I would have sent this via messenger but realized the time difference and didn't wanna wake you lol I have decided to make a flange and eventually split the mould, I'm confident I can do it and that way it will make it much easier to work on that recess bit. The picture below is what I have done today so far and the second picture is of my rear hugger I made for my motorcycle awhile ago, no vacuum bagging just stippling with a brush, it turned out really good. Edited 5 Years Ago by dilligaf76
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