Mould split lines

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Mould split lines

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Robert72	R Robert72 posted 6 Years Ago HOT Topic Details
R Group: Forum Members Posts: 57, Visits: 151	My mould is a basic tube 1.5m long x 300mm dia. So I have bolted the halves together to rub down the split. I have attached a picture of the inside. It shows the splits, and you can see how rough it is at points (this is the worst bit). Do I try to make the split better, or I am I worrying about nothing? I just don't like the roughness of it. If I leave it as is, I would imagine at worst it will mean buffing a bit of resin off the finished tube, which isn't a deal breaker. Any recommendations?..... If I was to clean up the split lines, I would imagine the best way would be to get one half flat and apply release to it, then lightly chamfer the other half, then bolt them together, then smear gelcoat in to the join, then buff it down?
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Hanaldo	Hanaldo posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Probably a bit much effort for what it's worth, you will always have a flash line that you need to clean up after. Having a tidy parting line in the mould makes it a touch easier, but unless the split line is 1mm thick then it is generally always easy. In any case, I am an advocate of putting all your effort into the mould, so it's not a waste of time. Just be aware that you will still have a flash line to clean up.
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Robert72	R Robert72 posted 6 Years Ago HOT Post Details
R Group: Forum Members Posts: 57, Visits: 151	+x Hanaldo - 10/14/2019 10:19:33 PM Probably a bit much effort for what it's worth, you will always have a flash line that you need to clean up after. Having a tidy parting line in the mould makes it a touch easier, but unless the split line is 1mm thick then it is generally always easy. In any case, I am an advocate of putting all your effort into the mould, so it's not a waste of time. Just be aware that you will still have a flash line to clean up. Thanks Hanaldo
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MarkMK	MarkMK posted 6 Years Ago HOT Post Details
Group: Forum Members Posts: 338, Visits: 2K	In terms of getting a neat and consistent parting line on split moulds, it is nearly always going to be impossible to get popular flange making materials right up to the pattern unless it's a completely straight/flat piece or, in the case of curved shapes, you have the means to machine cut the flange material to exactly match the patterns profile. Even then, there's always a chance of some gel coat leaching under the flange material as it's brushed into the angle, I think On the last split mould that I made, I used narrow strips of 5mm sheet wax to create the parting line and then cut out the flange material to fit as closely as possible to the surface of the wax strip. Filleting wax was then used to fill the slight gap between wax strip and the polypropylene flange, which was supported by foam blocks temporarily glued to the reverse and stepped slightly to overcome the width of the sheet wax. It resulted in a very slight step in the split above the sheet wax, but the consistent angle line it created and the fact that it is adhesive backed made things a bit more straightforward Just an idea, should anyone be struggling to get a neat parting line, especially on curved items where getting filleting wax neatly applied might be tricky Edited 6 Years Ago by MarkMK
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