Duratec H/G Clear Exposed

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#1

So for 6 months i left a part in the green house during a typical British summer (no it didn`t rain all the time lol) The part was made with duratec in the mould first then infused with epoxy, so far i can say there is no sign of yellowing compared to a finshed part which by the way has not been exposed at all and neither has it been clearcoated.

So do you realy need to clearcoat Duratec to protect it, will the epoxy break down, questions, questions, i suppose the answer maybe eventually one day and maybe.

Anyway comparison pics below, the unfinished part has been exposed for the 6 months.

It`s back to the green house for the winter and another summer.
To be Continued.

#2

I’ve basically got the same results. I coat all the motorcycle fenders with the duratec clear and there hasn’t been any signs of yellowing on even 2 year old fenders.

#3

…buit there sure are alot of brownin CF car hoods out on the roads of So. Calif.!

Maybe send a sample piece to a desert area…:stuck_out_tongue: rain & clouded skys doesn’t help!:wink:

#4

well lucky for me that racebikes get minimal exposure. :stuck_out_tongue: or they crash and destroy it before it can go brown :smiley:

#5

Werksberg, i guess the socal sun will brown the part a lot faster than our climate but surely any coating to protect a part is not going to protect it long term whatever is used. I mean where i live a regular wax and polish on the Duratec will probably suffice.

Ive tried various methods and materials to clearcoat the parts but am concerned about the bond, ive used clear etching primers and can still get a crazing of the clearcoat around a nut and washer after a while. Hence my testing polyurethane clearcoat with as the data sheet states excellent bond to per.

I like Duratec and i know i have a good bond between that and the epoxy so my testing by exposure of Duratec is a way of finding out if i can dispense with a clearcoat (possibly for UK climate only)

Ive tried using surfboard water clear (wax in obviously)in the mold first instead of Duratec but as youd expect the wax slides off any slant/vertical surface.

I`ll continue testing the polyurethane and maybe use that for clearing any parts exposed long term and plain Duratec as a finished surface for all other parts.

Baz

#6

I thought the HG Clear was not UV stable?

#7

I live at 5000 feet elevation (5900 actually) and I put a part I made 6 months ago that has “marble clear” polyester gel on it. As its not really UV stable.

I live in the desert and the elevation makes for more potent UV penetration. Ive left the part sitting on the roof of the house for this six months to be battered by sun, rain and dirt storms.

So far it looks the same and Im guessing it will only take a minor buffing to get the gloss back.

Although I have to admit, I prefer the super gloss look of clear thats pristine.

#8

perfeng as far as i know HG clear has no UV protection, but my tests so far in UK climate show no signs of browning of the epoxy. The epoxy is really so thin due to infusion that i think maybe unless exposed to full sun virtually every day why clearcoat. The Duratec gives excellent clarity and if used in the mold and left to harden the epoxy bonds to it very well. Im not against clearing with acrylic/cellulose its just the bond to the Duratec that concerns me. Sure you can use etching primers and ive tried clear ones but the bond is still not that great especialy when using nuts and bolts or screws after a while the bond breaks down and the clearcoat cracks and crazes, but this doesnt happen with just Duratec as a gelcoat.

hybrid, glad to see someone else testing the climate on their parts.

Baz

#9

tz250, do you use Duratec as a clearcoat after infusion then, i mean what do you use as a gelcoat in the mold first. I havnt tested it myself but i thought that the Duratec doesnt bond well to epoxy only the other way round. Do you have any bond issues on the bike parts where bolted.

Baz