Where to split mould?

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Where to split mould?

Author	Message
John Elshaw	John Elshaw posted 7 Years Ago HOT Topic Details
Group: Forum Members Posts: 5, Visits: 34	I've made some basic trim pieces and have had good success, now I want to try this door pull for my car. Where would you recommend I divide the mould sections? I'm guessing this will need to be 3 pieces, correct? Any help greatly appreciated.
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John Elshaw	John Elshaw posted 7 Years Ago Post Details
Group: Forum Members Posts: 5, Visits: 34	One more thing, the underside of the pull where your fingers reach should be smooth although aesthetics aren't as important on the back side.
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Warren (Staff)	Warren (Staff) posted 7 Years Ago Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	That is going to be far easier to make a 2 part item - an outer piece then inner moulding. To make it as a one piece part with split moulding would be extremely difficult IMO. You could make the mould but then the pull area would be a very thin area to try an lay up into - even as wet lay, let alone trying to get a bagging stack for more advanced processes. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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John Elshaw	John Elshaw posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 5, Visits: 34	+x Warren (Staff) - 12/5/2017 9:37:46 AM That is going to be far easier to make a 2 part item - an outer piece then inner moulding. To make it as a one piece part with split moulding would be extremely difficult IMO. You could make the mould but then the pull area would be a very thin area to try an lay up into - even as wet lay, let alone trying to get a bagging stack for more advanced processes. I think I'm following. So to be clear I should make a top piece, a 2nd bottom piece, and then bond the two together?
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Hanaldo	Hanaldo posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	+x John Elshaw - 12/6/2017 2:40:26 AM +x Warren (Staff) - 12/5/2017 9:37:46 AM That is going to be far easier to make a 2 part item - an outer piece then inner moulding. To make it as a one piece part with split moulding would be extremely difficult IMO. You could make the mould but then the pull area would be a very thin area to try an lay up into - even as wet lay, let alone trying to get a bagging stack for more advanced processes. I think I'm following. So to be clear I should make a top piece, a 2nd bottom piece, and then bond the two together? More like an outer and an inner than a top and bottom. So basically, the outer is the part that you see in those pictures. Flange around the outside and block off the hole in the middle with wax so you don't have any undercuts. Make your mould of that side and allow to cure. Then flip it over, remove your temporary flange materials (remembering to put release agent on the new fibreglass flanges!) and the excess wax from the underside of the pull area, and then remould that side. The tricky bit will be in navigating the mounting on the reverse side, as I assume it clips in rather than bolts in? You may want to pull them off and have a look at the inside. Post pictures of it here if you need a hand deciding where to go from there.
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John Elshaw	John Elshaw posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 5, Visits: 34	Here are some better photos of the part. Hopefully this helps. Here's another possibility if the above part isn't possible, although I'm not a huge fan of the pull straps in the car, it is a standard option on the Porsche 911 RSR cars.
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John Elshaw	John Elshaw posted 7 Years Ago Post Details
Group: Forum Members Posts: 5, Visits: 34	+x Hanaldo - 12/6/2017 5:13:48 AM +x John Elshaw - 12/6/2017 2:40:26 AM +x Warren (Staff) - 12/5/2017 9:37:46 AM That is going to be far easier to make a 2 part item - an outer piece then inner moulding. To make it as a one piece part with split moulding would be extremely difficult IMO. You could make the mould but then the pull area would be a very thin area to try an lay up into - even as wet lay, let alone trying to get a bagging stack for more advanced processes. I think I'm following. So to be clear I should make a top piece, a 2nd bottom piece, and then bond the two together? More like an outer and an inner than a top and bottom. So basically, the outer is the part that you see in those pictures. Flange around the outside and block off the hole in the middle with wax so you don't have any undercuts. Make your mould of that side and allow to cure. Then flip it over, remove your temporary flange materials (remembering to put release agent on the new fibreglass flanges!) and the excess wax from the underside of the pull area, and then remould that side. The tricky bit will be in navigating the mounting on the reverse side, as I assume it clips in rather than bolts in? You may want to pull them off and have a look at the inside. Post pictures of it here if you need a hand deciding where to go from there. Something like this for the outer part?
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Warren (Staff)	Warren (Staff) posted 7 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	The screw block on the rear would almost certainly need to be bonded on separately, perhaps a piece of suitable plastic cut to shape or even make a mould and resin cast a block with a small flange around it to increase the bonding surface area and hence bond strength. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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