Carbon Tuner
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Hey Guys,
First of I want to say I love what you guys are doing here.
I know the power of forums and am extied to be apart of talk composites! Ive looked around for other forums like this but theres nothing good out there. Also, all those videos and explanation on the websites enspired me to get started in making my own parts.
Anyhow I have made my part a few times now. First few pieces werent so bad but not perfect, which is my goal. After tackling getting everything to fit and form to the mold I still keep finding small inholes across the surface of the part...
At this point I am stuck. Could it be the surface of the mold? Seems to keep hapening so I assume I am doing something incorectly.
Any help would be appreciated,
Donnie
If Brute Force Isn''''t working your not using enough...
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Paul (Staff)
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Hi Donnie, Thanks for the kind words. Pinholes... everyones worst nightmare!  You should be able to get rid of them though, assuming that you are working with a bag that has been tested for leaks using the vacuum drop method, they can be caused caused by a number of factors... release agents and mould surface isn't normally the issue but using a chemical release agent such as our easylease system can improve the surface flow and improve the situation, however your problem is more likely to be elsewhere. If the pinholes are just in the corners this will be due to the fibre and/or vacuum bagging materials not being adequately 'pressed' into the corners, you must make sure that the materials have enough room to get tightly into the corners, pulling the vacuum slowly and pushing the bag into the corners as you go with help here, you want to avoid it having to stretch. We somtimes use blunt tools with breather wrapped over to drive the bag into the corners. If the pinholes are all over the surface this will probably be due to too much resin being drawn from the part, quite common on smaller mouldings, I would try closing the vacuum line a few minutes before the resin feed to allow more resin into the part this should help loads. The reason for this is that if there is too much resin drawn from the part the resin will 'wick' into the fibre leaving pinholes on the suface of the part at the nodes (gaps between the strands) this is not an air void, it is acctually a vacuum void! If you are still having issues then a few photos of the problem areas could help me to work out what's going wrong, i'm sure we can get them coming out perfect though! Let me know how you get on.
Paul StathamEasy Composites / Carbon Mods - Technical
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Carbon Tuner
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Group: Forum Members
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That was it man, Not enough resin... I let it fill for a few seconds after I closed the vacuum side, they turned out great. First one I tried like that I got a small bubble on the underside in a corner, but that was because I was fighting the mesh in the corners. Now I know I can leave it out of the corners for small parts or really tight spaces. Second one just had a baby hole on the top but I filled it and its good to go.
I tried getting some pics, is it me or is this stuff hard to take photos of??





Here they are, also you can see a little strand got away from me and ended up on the surface of the part. At this point I was not being to careful, needed to see if I could stop the pinners...
Now that I have 2 seatbelt covers I can post them up on my website. Not that I think anyone will be running toi get em but I can now move on with the product photos haha!
Next step is to get these things coated, they will see lots of sun. I am determined to do my lacquering "in-mould" but for now I will do it after the part is cut out and buff it. Guess I'll google around try to find the best lacquer,might just use a clear coat for these ones.
Anyone know how to get a matte finish on a lacquered or painted part? do they sell a matte clear coat?
If Brute Force Isn''''t working your not using enough...
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Carbon Tuner
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Group: Forum Members
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One of my Proudest inventions!
If Brute Force Isn''''t working your not using enough...
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Paul (Staff)
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Nice one,
Glad to see that it sorted out the problem for you, those parts are looking really nice.
A really good quality automotive 2-pack clear-coat should give them a really nice finish can't wait to see them all trimmed up. you can get satin finish clear-coats but I find you can get better results by wet sanding the laquer with 1500grit or a fine scotch-pad, you get a really nice flat satin effect that way.
That's a pretty neat resin mixer do you not find that it whips too much air into the resin though? might have to give it a go! we use jiffy mixers for larger batches of resin the make light work of it too.
Paul Statham Easy Composites / Carbon Mods - Technical
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Carbon Tuner
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Group: Forum Members
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Joe
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Did you already try with a resin impregnated syringue needle ? Cool addition to your Elise btw.
        A $1000 electronic device will always protect a 10 cents fuse
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Miro
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Hello, I am from Slovakia and I have a problem. Please advice. I tried to make a carbon fiber plate mirror finish with vacuum infusion process. I did everything like in your video on youtube but the whole surface of the mirror side, I have bubbles. Please help me where I made a mistake. Sorry for writing to English via Google Translate. Tank you Miroslav of Slovakia Bratislava
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Shaneer22
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Make sure temperature your working in is around 20c also degassing your resin makes huge difference,you can make your own chamber take your time and make sure you have no leaks,to combat leaks if parts not to large envelope your part,I have found flanges for infusion if not perfect can be a pain to seal if not impossible.
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Matt (Staff)
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It really is most likely to be that you're not undertaking the infusion at 'full vacuum', if your vacuum pump cannot put 100% vacuum (-1 bar) then these pin holes will occur. A leaking bag can also be the cause of low vacuum and so you should make absoltely sure that you have a totally sealed bag (perform a leak-drop test for at least 30mins, maybe even a few hours to be sure).
You should also ensure that you leave the project slightly 'resin rich' by clamping off the vacuum line soon after clamping of the feed line.
Get these things right and there should be no reason for pin holes in your surface finish.
--Matt
Matt Statham Easy Composites / Carbon Mods - Technical Sales
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