Should I have made mould deeper?

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Should I have made mould deeper?

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carbon man	carbon man posted 4 Years Ago HOT Topic Details
Group: Awaiting Activation Posts: 86, Visits: 1.2K	I have moulded this fuel cover but struggling to make the part without bridging around the edge. This is prepreg. I'm laying 1 xpreg surface ply and 1 backing ply. Laying it in one full piece. And tried debulk for 30mins to. Should I have made the mould of filleting wax a bit deeper? Or should I be laying a circle of carbon and then go around the edge. But as this is a cover I figured I couldn't do that and overlap the carbon joins making it to thick. Thanks
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Hanaldo	Hanaldo posted 4 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Have never managed to make a fuel cap that didn't have this issue haha, so dont beat yourself up. Luckily with pre-preg you can be very neat about it, so I find it easiest to cut your plies so that they are only 1 or 2mm bigger than the part and you have very very little overhang material. Obviously this means you have to be very careful placing the plies into the mould so that you don't end up short anywhere, but it should be quite easy. What this will mean is that there is very little material holding on to the flange, which will allow it to slide into place easier. As a side note - covers should not be so tight that a single overlap of carbon makes them not fit, so it should be perfectly possibly to do it with a slip joint as well. You're only talking about ~0.25mm, and you realistically need a gap for adhesive or whatever you are going to use to hold the cover in place, so it shouldn't matter.
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carbon man	carbon man posted 4 Years Ago HOT Post Details
Group: Awaiting Activation Posts: 86, Visits: 1.2K	+x Hanaldo - 8/2/2020 2:31:42 AM Have never managed to make a fuel cap that didn't have this issue haha, so dont beat yourself up. Luckily with pre-preg you can be very neat about it, so I find it easiest to cut your plies so that they are only 1 or 2mm bigger than the part and you have very very little overhang material. Obviously this means you have to be very careful placing the plies into the mould so that you don't end up short anywhere, but it should be quite easy. What this will mean is that there is very little material holding on to the flange, which will allow it to slide into place easier. As a side note - covers should not be so tight that a single overlap of carbon makes them not fit, so it should be perfectly possibly to do it with a slip joint as well. You're only talking about ~0.25mm, and you realistically need a gap for adhesive or whatever you are going to use to hold the cover in place, so it shouldn't matter. Ok thanks, il try that again this morning. I might try the backing ply as a single circle in the main part and then lay a strip all around curve. I used 1mm sheet wax. Should I allow a bit of room and use 2mm next time? If 2mm tho it might not allow the fuel door to open on the car?
	Reply Like 2
carbon man	carbon man posted 4 Years Ago HOT Post Details
Group: Awaiting Activation Posts: 86, Visits: 1.2K	+x Hanaldo - 8/2/2020 2:31:42 AM Have never managed to make a fuel cap that didn't have this issue haha, so dont beat yourself up. Luckily with pre-preg you can be very neat about it, so I find it easiest to cut your plies so that they are only 1 or 2mm bigger than the part and you have very very little overhang material. Obviously this means you have to be very careful placing the plies into the mould so that you don't end up short anywhere, but it should be quite easy. What this will mean is that there is very little material holding on to the flange, which will allow it to slide into place easier. As a side note - covers should not be so tight that a single overlap of carbon makes them not fit, so it should be perfectly possibly to do it with a slip joint as well. You're only talking about ~0.25mm, and you realistically need a gap for adhesive or whatever you are going to use to hold the cover in place, so it shouldn't matter. Also, iv tried everything but can't get the curves uniform and smooth ish to fit tidy. I'm having the dremel sand the back of the part. Any advice?
	Reply Like 2