uv protection what is best to use

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#1

Hey Fam,
Forgive me for asking this question again, I am sure it has been addressed several times. I have searched the forum and cannot find a topic at all. Now before you rag me, it might be because of my cheap tablet, but anyway I am fabricating CF parts for motorcycles and need a good method to UV protect them, for parts for that will have the CF finish. I am using Epoxy Resin, which left un-protected will yellow after exspoure to sun over time.

Rather it be a professional set up with compressor which I have, spray guns I will buy if needed, paint booth I will build or I have heard that you can get a quality 2k in a can that can be a used. :cool:

I think you guys know what I am asking any advice would be greatly appreciated and sincerely,
Thank you in advance

Soja:confused::smiley:

#2

A safe bet is 2K automotive clears. There are some cans on the market that are 2K, or go with standard mix and spray from a gun. Clears can be very finicky to apply and get a good surface. There is a learning curve and typically results are the combination of experience and quality of spray equipment used…

#3

I have heard that once you use the can you must use all of it because the product will harden and not allow additional spraying for other parts. As we all know careful planning must go into carbon fiber parts. I have got that down pretty good. I don’t want to buy allot of clear coat products to try, although that would be my best teacher, due to the fact if it doesn’t give me the results I’m looking for, money wasted :notrust:

Anybody try the Wr-Lpu from system 3? :cool:

#4

That is true however… You can refrigerate the aerosol and also freeze the unused portions. Careful time out procedure can yield an aerosol for 72-96 hours before they cure.

Another option is using the preval system. Just as cost effective as aerosol. But… Sometimes customers want their specific coating applied and this is where preval is better.

The finish is easier to apply with the aerosol as far as a 2k system.

Good luck.

What are you planning on making?

#5

German Advanced Composites make an in mold clear coat that you apply as the first layer. It may be the easiest way of getting UV protection without needing to buy any spray equipment.

#6

we used a product called tinuvin to act as a UV blocker in our surfboards before we started using a different epoxy system that already had UV protection in it. If you dont know, the surfboard industry is VERY anal about yellowing resins in the last 5 years, so much so that the industry has taken to adding a hint of violet tint to the resin just to fool the eye into thinking that the boards are glowing white rather than just bright white… (lowers the kelvin value, or the “optical temperature” of the appearance of the board to the eyes)

anyways, you may want to look into resin additives, then you may be able to get away with a less-expensive clearcoat material

-david

#7

just came across this, looks interesting…

http://www.oneoceankayaks.com/Epoxtest.htm

I agree with the resin additives… some of the epoxy i’ve used has this coloration and it does look more clear with the added color as David pointed out.

#8

Thanks for the feed back guy’s. I really do appreciate it. I began to check into some of the products that you guys have suggested. I have sent an email to Basf for the tinuvin and have not got a response yet

Would like to get some more feedback on that one tinuvin.Why did you stop using it? Where can I get some I’m in california?

Looked into the surfboard industry and getting some info. From these guys for some is like pulling teeth. I am not even in their industry. My parts are for motorcycles. Well thanks FAM looking still, going to start out with Resin Research and begin some rudimentary testing. :cool:

#9

we stopped using it because we started using epoxy resins that already had UV blockers in them.

in my opinion (and according to tech. data sheets) the epoxy systems that most surfboard manufacturers use is structurally inferior to something you would use on an airplane for example. Its more similar to a clear coat, or bonding epoxy, like west systems for example. However it is generally cheaper than the structurally superior resins, and it is MUCH more optically clear, and bright. Again, at the moment, the surf industry is addicted to making surfboards as bright white as possible.

so again, basically we switched because it was cheaper and made a better looking board, at the expense of some structural strength. In my opinion, i would take a longer lasting board over a prettier board any day. but im an engineer, not the marketing guys…

also, keep in mind that if you are going to do carbon fiber parts, or anything that doesnt have a substrate like foam that you are trying to provide a clear window to underneath your laminate (like a white foam surfboard blank), you dont need a water-clear resin system. also, some surfboard systems have some violet tint in the resin to fool the eye into thinking that its “whiter” over he top of the white foam blank. there is a drawback to this however: when these resins are used for a carbon layup you can see the violet tint of the resin on top of the carbon (or anything else you want to be black / dark)… makes it look weird in my opinion, i dont care for it.

we were getting our tinuvin and other additives from Germany while we were still using MGS resin, also from Germany. ive never had to source it from here (im also in california), but ill take a look around real quick…

-david

#10

Thanks David, my carbon fiber parts will have no foam backing or (core) it will fit neatly over an OEM part for cosmetic and armor protection. I am working towards a high gloss finish as well as UV protection. As I experiment with different epoxies I believe that I am drawing nearer to the desired goal of a functional, cosmetic appealing part that will last and raise eyebrows in the market I am in. It is gentleman and forums as this one that helps utilise a wealth of experience to glean from giving the hobbyist and seasoned fabricators a place too share past experiences, techniques and solutions. For that I am grateful.

Thanks again Fam.
Soja

#11

For skinning (like your doing) I use a ultra clear surfboard epoxy. Works great and is very stable.

#12

I am not skinning, I have made molds from the plug and laying laminate for a complete part.