Hi guys, hoping one of you might be able to shed some light on some ongoing issues i’ve got with the above product. Now unfortunately i’m not a surfer but seems you guys use this stuff all the time.
Now i use this for carbon fibre skinning/wrapping and i keep having the same issues of white marks in my cured resin. I originally tried it 2 yrs ago and had these issues so stopped using it. Decided to give it another bash as the mix has apparently changed but alas the same again. I’m based in the uk so don’t have access to your sunny weather lol.
The coats need to be super clear and air bubble free for the weave to show nicely so a heatgun is the only way to remove them but i’m aware it isn’t ideal to heat epoxy and let it cool again.
Breakdown of how i use it:-
1 coat of kk on the part to stick the carbon down.
Then 1 coat to seal it...left overnight then trimmed to shape and roughly sanded to allow the subsequent coats to adhere.
Then 5/6 more coats laid down in 20 minute intervals with a very quick blast with a heat gun on low temp to remove any air bubbles (previously tried without heat but same problems)
Every coat is mixed using a new paper cup and tongue depresser with a new brush for every coat.
Whole thing is left overnight then sanded dry to remove any blush then wet sanded with120/240/400/600/800 before any 2 pack laquer is applied.
Obviously mixed in a 2:1 ratio as directed.
Exactly the same process i use for small and larger parts with my normal epoxy from easy composites of which i get no trouble like this. Only difference being that has a longer pot life/tack time etc
I don't use additive F as previously i found it clouds the part when dry.
This is all done at roughly 20-22 degrees constant.
Also i find the 1st coat down pools into drops a lot and doesn't flow until i get a few coats down
My guess is it has to do with you not waiting for cure between coats. Also the forming drops, rather than flowing is a concern.
I hope you aren’t using a tack cloth or anything. If the cloth rejects the epoxy, there is contamination somewhere. Maybe in the bucket, maybe in the cloth.
Also epoxy doesn’t like to cycle from hot to cold when in storage. If you heat the jug, then pour, the epoxy chemicals will separate, the thinner ones pour first, and the thicker remains.
Here’s an interesting thread on doing decorative carbon fiber overlays. You may note that he used Silmar polyester resin (the exact stuff traditionally used on surfboards).
It almost looks like it is cracking or glazing between the coats. It looks like a mini delamination from not bonding. I think it is whiff marks where you are superheating the epoxy from the heat gun. You are burning / scoring the previous coat, then putting a faster cooling non bonding coat over the top of it. it's too hot under the top coat, and making wierd things happen.
I need to understand why you are using so many coats to get a build up? I would do in in no more than 2-3. Not sure what you are building there, but as long as you are getting your epoxy quite warm and loose before using you should not be getting any bubbles. I only use the heat gun when I have a very thick coat of epoxy over the glass. I only use to to decrease the viscosity of the epoxy..But you can't let it burn what's underneath. I think thats whats happening?
I’m going back to my days of making custom fishing rods for offshore sportfishers. The finish I use is a 2-part epoxy and it is critical that you do not introduce air into the resin before applying or during application or else you will get effects like that in the finish. For mixing the epoxy it is critical to not stir the resin. The method to use with rod finish epoxy is to use your stirring stick stationary and rotate the mixing cup so it more or less folds the mix together without mixing air in. The worst thing you could do is mix the expoxy like you are wipping eggs. When applying the epoxy you want to flow it on again so as to not introduce air. Other things that can cause that effect are contaminants in the cup or thinners. With fishing rods we use a slow rotating rotissery motor to spin the rod while the finish cures so it doesn’t sag and to get a perfect finish and remove any tiny air bubbles heat is applied while the rod spins on the drying motor. Hope this helps.
Could be the paper cups. Maybe they’re waxed cups or just scraped too hard when mixing. try using plastic ones. My wife saves all the little plastic containers from salsa and yogurt. Its surprising how quickly they can add up.
It is carbon overlaying, so an original part covered in carbon to mimic it as real. Its very popular in car culture snd serves me as a little side business
The kk wets out fine on the dry cloth. The pooling happens when i use it as a basecoat before cloth is applied so you brush it on, all looks fine then 2/3 minutes later its forming droplets even though the part is sanded heavily and cleaned with isopropanyl.
I have to use that many coats to completely cover the weave so there is something to sand and make smooth as once this stuff gets out in the heat of a hot car we encounter shrinkage.
3 coats barely covers the weave
adyou can see if i leave it and sand that i’m hitting the cloth snd destroying the 2/2 weave make up.
White stuff is on the surface.
I can’t see any other way to get bubble free mixs other than a degassing chamber, and when brushed on that adds more. Certainly not as many bubbles with this resin as my usual one.
Cups are wax free and new every coat, as is brushes and mixing sticks.
As previously stated i use that exact method and consumables with my normal epoxy with heavier heatgun use with no issue. It is a slower hardener granted
The fast kick epoxies were formulated for a production environment. Since you’re going for the look more than the physical properties maybe you could consider changing things up. Use the epoxy to lay up the part, then use a urethane like Resin-X as a tie coat to bind the epoxy with a vinylester or polyester finish. The company that sells Resin-X also sells a high gloss UV cure finish that you spray on. Maybe use the urethane for the fill and the UV gloss for the finish. They’re fast, too.
I read something interesting on a lesser known epoxy manufacturers instruction sheet. (this could be incorrect), "It is not the heat from the torch that is lifting the air bubbles, It is the CO2 from the flame." They went on to suggest using a straw, and blowing.
Very nice work there, and welcome to Swaylocks. My reply was provided as general information for all members. Was hoping G L, or some other expert might comment
CO2 also comes in tanks, (including paintball). An enclosure could mean a micro flow valve would not be needed, The work should sit on the enclosure floor, because CO2 sinks. The straw was for an affordable experiment.