Prepreg + Nomex honeycomb

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Prepreg + Nomex honeycomb

Author	Message
Carbonnewbie	Carbonnewbie posted 8 Years Ago HOT Topic Details
Group: Forum Members Posts: 3, Visits: 55	Hello! I am planning to make carbon fiber + nomex honey comb sandwich sheets, about 1.5 m2 pieces. The sheets are not 100% straight, but no radical shapes neither included The skins would be app 220g/m2 carbon, and inside 4,8mm Nomex, 5mm thick. What are my possibilities? I red about dipping the honeycomb in epoxy. Also about the adhesive films etc. Even some sources say, that I can do everything in one pass, without glues (when using prepreg)..... Only the surface facing to the mold has to be perfect, other side does not matter at all. Carbonnewbie Tags honeycomb core nomex Prepreg Edited 8 Years Ago by Carbonnewbie
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carbonfibreworks	carbonfibreworks posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 292, Visits: 4.5K	Hi If you try To use the honeycomb core without a resin film in one go with pre preg you will starve the carbon of resin giving a poor quality component in strength and looks, a better method would be to used the EC specific adhesive although you could coat the surfaces with a laminating epoxy as a second best option. Regards Chris Carbon fibre works LTD
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Dravis	Dravis posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	Hi! If you only need the mould -facing surface to be perfect, and the curvature of the part is very slight, then you can do two prepreg "skin" parts from the mould, then key one on the outside and use as the inner "skin" You can then use a thin rolled on (or even sprayed) layer of laminating resin on the two "skins" and compress the whole "sandwich" back in the mould, just using flat bags of sand to keep the sandwich together .. Good luck "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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f1rob	f1rob posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 237, Visits: 4.8K	When you say "perfect" what exactly do you want ? If you want perfect out of the mould your only choice is 2 shot with film glue You can get some pre preg resin systems that are core bondable (mtm28b for example) that you could do it in one hit with but you will almost certainly need to to lacquer to get a perfect Finnish A debulk on your 1st ply will help If you are doing a autoclave cure always use a vented cure
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Carbonnewbie	Carbonnewbie posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 3, Visits: 55	Thanks for replies! Would this make sense: Making the first skin by resin infusion, with peel ply. After curing adding an adhesive film on the cured skin, followed by honeycomb, and on top of that a Prepreg (for instance mtm 28 ) and then vacuumbagging the whole thing and curing in the oven?
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f1rob	f1rob posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 237, Visits: 4.8K	"core bondable" means it doesn't need film glue so you don't need it for your 2nd shot if you used 28b or Aother similar resin system if you went 2 shot why would you do 1st shot infusion ?
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f1rob	f1rob posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 237, Visits: 4.8K	"core bondable" means it doesn't need film glue so you don't need it for your 2nd shot if you used 28b or Aother similar resin system if you went 2 shot why would you do 1st shot infusion ?
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Carbonnewbie	Carbonnewbie posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 3, Visits: 55	hello! just to make sure that the surface of the skin would be superb.
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f1rob	f1rob posted 8 Years Ago HOT Post Details
Group: Forum Members Posts: 237, Visits: 4.8K	An AAO pre preg will give a good Finnish and you also have a stronger more resilient Finnish plus a better part with better resin ratio Don't get the depth of resin you would with infusion but do you want "bling" or performance ?
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