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Massimiliano
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Hi, I would like to infuse the attached mold with carbon fiber, several layers of 380 gsm 12k twill carbon. What is the best way to cut the fabric and place in the mold, also to avoid tows separation at the edges? 
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Hanaldo
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Just give it a go man, you'll quickly learn what the material can and can't do. Start with the first layer and take your time, if you mess it up visually then just use that layer as one of the backing layers and try again.
There's not really too many ways you can do it that will make your life any easier, its a reasonably tricky shape. You're going to get a little bit of distortion and you will have to work a bit to make sure there's no bridging. If you were using pre-preg you would do the flat face as one piece and then the vertical sides could be done separately perhaps with the material at 45°. You could try that with dry fabric, use a bit of spray adhesive to stabilise it a bit, but it won't be as neat and easy as pre-preg is. You can do it as one big piece that you gently position and then trim the excess and put relief cuts in the corners where needed. This will give you the biggest challenge with bridging but potentially the neatest result.
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Massimiliano
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Group: Forum Members
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+xJust give it a go man, you'll quickly learn what the material can and can't do. Start with the first layer and take your time, if you mess it up visually then just use that layer as one of the backing layers and try again. There's not really too many ways you can do it that will make your life any easier, its a reasonably tricky shape. You're going to get a little bit of distortion and you will have to work a bit to make sure there's no bridging. If you were using pre-preg you would do the flat face as one piece and then the vertical sides could be done separately perhaps with the material at 45°. You could try that with dry fabric, use a bit of spray adhesive to stabilise it a bit, but it won't be as neat and easy as pre-preg is. You can do it as one big piece that you gently position and then trim the excess and put relief cuts in the corners where needed. This will give you the biggest challenge with bridging but potentially the neatest result. Thank you! I was thinking of making a shape of the internal of the mold with paper and then cut the fabric to shape a little oversized and trim in the mold... good idea or bad idea?
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Hanaldo
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Group: Forum Members
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Good idea if it works, bad idea if it doesn't haha. Just give things a try man. I suspect it will be difficult to do like that though, it is a complex shape and the dry fabric is going to move around a bit. But that said, if you aren't used to laying up reinforcement and eliminating bridging then that may be even harder, so trying the template isn't a bad idea.
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Massimiliano
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Group: Forum Members
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+xGood idea if it works, bad idea if it doesn't haha. Just give things a try man. I suspect it will be difficult to do like that though, it is a complex shape and the dry fabric is going to move around a bit. But that said, if you aren't used to laying up reinforcement and eliminating bridging then that may be even harder, so trying the template isn't a bad idea. ... going to send the mold to Australia soon! 😅😄
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Massimiliano
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Group: Forum Members
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So I did it and I am not dissatisfied with the result. I have given a try to the MTI hose and very happy with it, but the resin inlet spiral left a bad print on the part: seems like the carbon under the spiral is more compacted than the rest. And the immediate surrounding of the spiral is a little raised. Talking about a fraction of millimeter, but still very visible. How can I prevent this in the future? 
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Lester Populaire
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+xSo I did it and I am not dissatisfied with the result. I have given a try to the MTI hose and very happy with it, but the resin inlet spiral left a bad print on the part: seems like the carbon under the spiral is more compacted than the rest. And the immediate surrounding of the spiral is a little raised. Talking about a fraction of millimeter, but still very visible. How can I prevent this in the future? Make sure you have enough bag above the spiral hose, then once the infusion is finished you pull the hose up into the fold of the vacuum bag. Either that or infuse from side to side if the geometry and part size allows for this.
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Massimiliano
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Group: Forum Members
Posts: 167,
Visits: 1.1K
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+x+xSo I did it and I am not dissatisfied with the result. I have given a try to the MTI hose and very happy with it, but the resin inlet spiral left a bad print on the part: seems like the carbon under the spiral is more compacted than the rest. And the immediate surrounding of the spiral is a little raised. Talking about a fraction of millimeter, but still very visible. How can I prevent this in the future? Make sure you have enough bag above the spiral hose, then once the infusion is finished you pull the hose up into the fold of the vacuum bag. Either that or infuse from side to side if the geometry and part size allows for this. Thank you! I will try the fold suggestion as mti videos suggest to place the mti hose all around the part (see the white line in my pic) and place the resin inlet in the middle.
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Hanaldo
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Group: Forum Members
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It's much better and much easier to just keep all the hoses off the part. Infusing from the centre is a good idea for larger parts, but for small parts it is really unnecessary and can cause you issues like you've experienced.
Just infuse from one side to the other. Run your MTI hose down just the one side. Less issues, and you'll use half the amount of MTI. How big is the mould? If it is under 0.5 metres wide, I wouldn't even bother using spiral hose on the feed side.
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Lester Populaire
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Group: Forum Members
Posts: 311,
Visits: 13K
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+xIt's much better and much easier to just keep all the hoses off the part. Infusing from the centre is a good idea for larger parts, but for small parts it is really unnecessary and can cause you issues like you've experienced. Just infuse from one side to the other. Run your MTI hose down just the one side. Less issues, and you'll use half the amount of MTI. How big is the mould? If it is under 0.5 metres wide, I wouldn't even bother using spiral hose on the feed side. While i agree with you and would do the same, for a beginner it would be safer with the inlet in the centre. With a little bit of bridging the racetracking on such a geometry can ruin your part when infusing from side to side. So make the fabrics have to lay in the corners really well.
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