I got pin air all
over my final coat which didnt start coming out till the 800 paper.
Wouldnt be a problem but the board is carbon fibre and it shows. Really
small ones. Looks like stars. I used epoxy for the final coat. Im
about to start polishing it but im affraid that the polish when it gets
into the pinholes will seal in the white spots. Its there anyway to
disolve this out with DNA or acetone? What should I do before I polish
and after to fix this problem. Also, going forward, how can I avoid
this. I hit the final with a heat gun quickly to pop the bubbles but
these ones were not even noticable and I guess were deep. I mixed in
DNA to my final epoxy coat to thin it out, just a little for better
flow. Is this the cause? Thanks in advance for all the help.
[img_assist|nid=1042435|title=Carbon Fibre longboard|desc=|link=none|align=left|width=100|height=75]
here is a pic of the board during the gloss coat.
Louie -------If you post this thread over in general discussion you’ll probably get more response. Alot of the guys that read and post general discussion rarely come over to the Industry forum.
Moved to general discussion…
The white is the sanding dust trapped in the holes, before you polish wash it out with water and detergent to see if they disappear/become less obvious.
If its really packed down - use the point of a pin to loosen it. If you have loads then you may consider doing another thin coat of resin to fill them, personally I would’nt bother.
Polish as normal, but be prepared for the pin holes to fill up again with compound and wax, requireing another wash down.
If it was me, and waater and deteregent didn’t get them out, I’d mix up some black water color paint and see if I could saturate the dust with color. Do that before doing polish, which I would guess would lock the dust in.
smarty pants!
Hey louie,
It’s not so much ‘pin holes’ in your gloss coat as it is fish eyes caused by dust and dirt settling into your hot/glosscoat.
To prevent (or at least majorly reduce) fisheyes on your next board
-
blow off board really well with compressed air. No compressor? Brush like crazy with a dust brush.
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wipe down with DNA and clean, lint free rag.
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drag a strip of clean masking tape over the board to pick up any dust left
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filter your resin before mixing - use clean bucket and mixing stick
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hotcoat and walk away. Try to reduce air movement around board as much as possible (this is the hardest part)
You still may get a few fish eyes from dust in the air but they will be shallow and sand out quick
~Brian
Just a quick tip to add for those who don’t have an air compressor. I have a shop vac that doubles as a blower, you just move the hose from the suction port to the exhaust port. Then I take the hose adapter I bought at Home Depot to connect to my planer and put that on the end of the hose. It works just like a water hose, reduce the amount of water/air that can get out, and you get more power. I use this set up to blow off my shaped blanks and after sanding.
If it’s actually dust in some very small pin air (which it sounds like), then baby oil wiped over the surface will make them disappear.
Hey Greg,
Thats exactly what I did. It worked for the most part but I still have a few spotts. For my next board, How would I go about not getting those? I hit it with a heat gun but these were so tiny and really in there that I couldnt see them thill the 600 paper brought them out. Board overall though came out nice and it was 100% epoxy. Here’s a link if you wanna see it.
http://fiveforty.multiply.com/photos/album/36/Carbon_Fiber_Board
Louie, that’s lush man, even my wife likes it.
Looks damn nice to me. I’d just keep using the baby oil trick. Air like that is something we just see on dark colors. Used to get it with polyester carbon boards as well and we used veggy oil or baby oil to minimize it. That’s how I knew the trick.
What did you use to compound/polish/wax that board? Looks amazing!
Ive always respected and valued your post, greg, so thanks for the info here. Ill continue to use that trick. One last tech question. I mixed in DNA to get a thinner flow for the polish coat. Could this be the cause of the airbubbles? On the bottom I didnt thin it out and it didnt have the same pin air problem. Also, I think I coated on a rising temp. Another possible cause? Thanks again.
I used the same process that you would with the poly boards sanded to 800 paper then used rubbing compound and then polish after. Little more work but basically the same process. Had to polish over a few times to get a real good gloss. Also had to make sure the epoxy was FULLY cured to get good sanding. Hope this helps.
Im in the Philippines so Ive had to test about 10 different epoxies that they use here for various applications and I’ve found a few with the clarity properties good for surfboards and that flow out nicely so I dont get fish eyes. You guys are lucky to have Greg and RR products.
DNA can cause that for sure. See if you can thin the stuff out with the brush instead. Also if you get the resin up about 38C before you add the hardener you’ll get wayyyyy better results. The resin will be thinner, it won’t blush as much and it’ll flow better. Gloss quickly though … resin kicks quick that hot.
Ah… hence the microwave. Ok Im excited to try that. Ill update this post later this week with some results. Thanks again, Greg.
Realy nice work louie, epoxy over darks is a real art in it’s slef and a great gloss,
The veggie/baby oil trick is a new one to me, will give that a shot when in the same position.
its old school but have you ever tried used mr.sheen furniture polish after the compound, with a polisher you can get a surprisingly nice shine, not that your doing anything wrong the polish job looks amazing , it took me about a year after I started using epoxy to figure out how to get a good shine, just thought if you haven’t you may like to give it a try?
thanks bro, I gotta give that one a try. Ive used the 3m high gloss before but never Mr. Sheen. Thanks for the info, I’m always looking for a better way to do things and I think for the art aspect of surfboard construction, the oldschool way is the way to go.