How to get a perfect join on a round part?

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How to get a perfect join on a round part?

How to get a perfect join on a round part?

Author	Message
NTF6	NTF6 posted 7 Years Ago HOT Topic Details
Group: Forum Members Posts: 13, Visits: 34	Hi, I am skinning a turbo inlet pipe that is round, tapers from one end to the other and also has a tight bend in it. Initially I layed down a first layer using 25mm plain weave CF tape because the inlet pipe was made up of two pieces and i needed the piece structurally joined before moving on. I have sanded the piece down ready for the next layer which will be the nice visual layer as seen when the piece is finished. My next step is to add another layer using 3k 2x2 twill but I would like advice on how to get a perfect join when I lay the CF on the resin and also the odd shape of the piece. I don't want the weave coming apart if I cut it and I also don't want to overlap the joint. Any advice would be greatly appreciated, btw, this is my first skinning project. Tags skinning turbo
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WR Composites	WR Composites posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 9, Visits: 158	I think braided sleeve would be ideal for skinning tubes instead of off the roll fabric. Edited 7 Years Ago by WR Composites
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Warren (Staff)	Warren (Staff) posted 7 Years Ago HOT Post Details
Group: Administrators Posts: 2.5K, Visits: 7.9K	As said, braided sleeve is the best way. It can be very hard to get the fabric to precisely meet in exactly the right place when using normal fabrics. Also depending on the diameter of the fabric, even if you aligned it perfectly down the tube, you might find it will never align perfectly around the tube. Warren Penalver Easy Composites / Carbon Mods - Technical Support Assistant
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Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	Layup one side to cover more than just half and let this cure. Sand lightly. Then layup the second side/half also doing more than just half. Wait until green (partially cured like rubber, 2 hours?) and then cut clean with knife (green trimming) and peel away the wasted edge. A bit of a technique but it could work well. Then resin coat sand/coat/sand/spray etc etc until you have your gloss finish. Or use pre preg and cook. The pre pregs will cut clean and sharp. I did this alloy pipe with pre preg. Fastacraft Facebook page Edited 7 Years Ago by Fasta
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WR Composites	WR Composites posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 9, Visits: 158	It would almost be easier to make the complete tube from carbon. Edited 7 Years Ago by WR Composites
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Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	Really? the guy is skinning and has no mould! Fastacraft Facebook page
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NTF6	NTF6 posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 13, Visits: 34	I did purchase some CF sleeve the right diameter but it was only available in 12k and wouldn't go around the curve without bunching up as it was quite stiff. Bear in mind that this item has a 90º bend in it and most of the bend occurs in the last half, I'll throw up a picture when I get home today. I would have also had to put it on dry and then apply the resin as it would've been a nightmare trying to put it on over the resin with the bend and taper in it. Edited 7 Years Ago by NTF6
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NTF6	NTF6 posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 13, Visits: 34	I was thinking if I apply the CF to the tacked off resin but then run a stanley knife down the CF at the exact point where the CF has stuck to the resin and where it hasn't, then sticking down the remainder until I get to my cut line and again running the knife blade down the CF on the cut line I did before as the Cf lays over on the dry CF. What do you reckon?
	Reply Like 4
NTF6	NTF6 posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 13, Visits: 34	WR Composites (16/05/2017) It would almost be easier to make the complete tube from carbon. Unfortunately I need the end fittings as they are and making a mould the same as this thing would be hellish.
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Fasta	Fasta posted 7 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	NTF6 (17/05/2017) I was thinking if I apply the CF to the tacked off resin but then run a stanley knife down the CF at the exact point where the CF has stuck to the resin and where it hasn't, then sticking down the remainder until I get to my cut line and again running the knife blade down the CF on the cut line I did before as the Cf lays over on the dry CF. What do you reckon? That could work too but you would have to really get that second cut right to meet the other one spot on. Might be an idea to paint your tube black so that any gaps don't show through? Usually these sort of engine bay parts are only only seen from one side, even more simple would be just to wrap with one piece and make sure your scissor cut overlap is on the unseen back side?? If you can accept that? Fastacraft Facebook page
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