How to get nice finish after bagging?

Talk Composites - The Forum for Advanced Composites

Back

How to get nice finish after bagging?

Author	Message
brummelisa	brummelisa posted 12 Years Ago HOT Topic Details
Group: Forum Members Posts: 20, Visits: 144	I wonder how I can get nicest finish after I have vacuum-bagged my CF without any air-bubbles. I don't use a mold, but a plug (I'm building a bike-frame) and the piece will be wrapped totally with six layers. Should I just paint with epoxy and smooth the surface by sanding and do this a couple of times to build up a surface and when that is done start to put on clear-coat? I have read somewhere that you can use micro balloons with epoxy, but is that just to use it as a filler or can I remove the tiny air-bubbles that can occur in the epoxy? Any idea? / Marcus
	Reply Like 2
Mr Rooty Tooty	Mr Rooty Tooty posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 15, Visits: 156	I'd sand down any high spots. Then paint on a couple of coats of epoxy. Then when that is hard I'd sand it again by hand until it smooth and even, starting with 240 grit wet and dry and working up to 800-1200. You may want to spray on a guide coat (quick spraycan coat in a contrasting colour) so that you can see any low spots when you have done the first 120 grit sand. Keep an eye on the paper, if the water running off starts turning black you have sanded through to the carbon cloth. This isn't that much of a problem as long as you stop sanding that area, it won't spoil the finish. At the end I'd spray on some 2k automotive clearcoat and if need be sand that flat with 1500 grit w&d and buff with an powered automotive buffer and cutting compound to get a glassy finish. If you look on the "projects" thread you'll see the bodywork I have done using this method.
	Reply Like 2
mhdghoul	mhdghoul posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 49, Visits: 113	im with the 1st answer , but my way is a little bit faster, 1st sand the high spots , just a little smooth sand don over do it or u will be ruining the cf , then apply 3 or 4 or even 5 layers of resin , just wait till each gets tacks so u will have thickness and leave it overnight to harden , this will give u a good surface to sand properly and make sure its sanded without any low spots , once u do that sand it to the 2000 grit and then you can polish or clear coat it , i prefer clear coat , it helps protecting from uv , a 2k as was said before is the perfect choice. best regards mhd alghoul mhdghoul@hotmail.com youtube channel :atmospherejo link is http://www.youtube.com/user/atmospherejo?ob=0&feature=results_main
	Reply Like 2
kylle	kylle posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 34, Visits: 101	mhd alghoul what type of clear coat do you use in auto parts? can it be with a air gun using epoxy? best regards Hugo
	Reply Like 2
mhdghoul	mhdghoul posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 49, Visits: 113	its a 2k clear coat with an hs hardner mixed 2:1 , it should be used with an air gun best regards mhd alghoul mhdghoul@hotmail.com youtube channel :atmospherejo link is http://www.youtube.com/user/atmospherejo?ob=0&feature=results_main Edited 12 Years Ago by mhdghoul
	Reply Like 2
Rootz	Rootz posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 10, Visits: 60	For information: If, like me, you're making up relatively small parts and don't have a compressor, you may be interested is this aerosol 2K clearcoat. The can has a button on the bottom. Once you've hit the button and mixed the clearcoat, you've got 8 hours to use it. You can stretch that to 24h in the 'fridge and I have a part-used can in the freezer. Will let you know how well it keeps there. http://www.specialistpaints.com/products/2k-clear-coat-canz "Well, it can't possibly be as good as real clearcoat!" Believe it, or not. I really is! By the way, something occurs to me on this subject: If you're planning to rub down and clearcoat a CF item, why wouldn't you simply paint several coats of epoxy into the mould before your surface layup, rather than painting epoxy onto the part once it comes out of the mould? Is there any disadvantage to doing it that way? Cheerz! Rtz Tags aerosol clearcoat Edited 12 Years Ago by Rootz
	Reply Like 2
Joe	Joe posted 12 Years Ago HOT Post Details
Group: Forum Members Posts: 310, Visits: 1.5K	Thx Roots for the 2k cans tip A $1000 electronic device will always protect a 10 cents fuse
	Reply Like 2