Botched fibreglass epoxy coat

Hiawathabuilder · Post by **Hiawathabuilder** » Sun Oct 11, 2009 6:54 am

Used 6 oz cloth and West System epoxy.
Started at 11 am until 11pm. Two coats applied. I heated the epoxy in front of a Halogen lamp to approx 80 F as the evening cooled the workshop.
Everything went smoothly until I used the squeegee as recommended to remove excess resin. Now I have milky white strips and visible milky cloth patches randomly through out the finish.
The only way I know of to correct this problem is to remove the epoxy and fibreglass by sanding down to the wood surface.
Did anyone out there have a similar misfortune?
Temperature was ok.
Mixing was ok
Did I press too hard or wait to long before using the squeegee.
Can I redo this without using the squeegee process?
I estimate an other 24 man hrs of sanding.

Rick · Post by **Rick** » Sun Oct 11, 2009 7:59 am

Temperature was ok.

What was the air temperature in the workshop... I have had epoxy go milky when air temp was low - 12C - and the epoxy absorbed humidity from the air turning it millky. This was not amine blush, and couldn't be washed off.

The solution was to sand off the milky surface and add another epoxy coat... the transparency was fine after that. Maybe try sanding at one milky spot and adding another coat of epoxy over the sanded area to see if becomes clear again. If that doesn't work, sanding off the glass will be necessary, or removal with a heat gun ( the epoxy softens and glass can be peeled off).

Preventing the milkiness from occurring again on the interior glass was done by heating the workshop up to 25C and keeping a dehumidifier going.

I eventually ended up painting the outside of my Huron because of all the scratching and bruising (also a milky color) and all that agonizing earlier on was overdone. The colors now appear similar to this...

Jim Dodd · Post by **Jim Dodd** » Sun Oct 11, 2009 8:02 am

Did you apply with a brush or a roller ?
It sounds like over worked epoxy to me.
There can be a lot of factors effecting this situation.
I would squeege shortly after application.
Once the epoxy has wetted out the cloth, and you've squeeged the excess, let it cure without disturbance.

Good luck
Jim

jturk · Post by **jturk** » Sun Oct 11, 2009 6:52 pm

I don't have an answer for you but I am so sorry that it happened, Be patient and you will figure out a solution.

Good luck.

Jim

Juneaudave · Post by **Juneaudave** » Sun Oct 11, 2009 10:51 pm

Bummer....Did you get the milky streaks during the wetout, the second coating, or both? Be nice to figure out what happened and it sounds like it was overworked...also ...you indicated that you heated your epoxy...how cool was your work area?

Moonman · Post by **Moonman** » Mon Oct 12, 2009 8:13 am

Sounds to me like you might have waited too long to squeegee. How long did you wait? Might the epoxy have started to set up?

moonman.

BradRob · Post by **BradRob** » Mon Oct 12, 2009 8:14 am

contact geugeon brothers at west systems .

tszpieg · Post by **tszpieg** » Mon Oct 12, 2009 8:39 am

Does it look something like mine?

I found the epoxy part of the building process to be the most difficult BY FAR. I have had virtually no experience with epoxy and fiberglass, and much of the literature I read on the subject just seemed sort of abstract in its description of the process. I think it is really hard to describe the whole squeegee process through words. So much of that is just 'feel'. And if you don't know what it is to 'feel' like, you're kinda taking a shot in the dark as far as achieving predictable results as a first time user. I think I started to develop the 'feel' of squeegeing' on the interior, and that is FAR from perfect. However, it is not as streaky as the exterior. I hope my next attempt at the whole fiberglass epoxy thing turns out better than my first.
It was a pretty big downer to see the streaks on my hull after spending SO much time fairing and sanding (not to mention the whole building process) , and be left with the the results I have.
BUT, I chalk that up to experience (or lack thereof), and I will try to improve on it with my next vessel. As I look back, I think my squeege pressure was too hard (experts please comment). From what I've read after doing more research, I think my next attempt will be done with a straight epoxy pre-coat, after which the glass will be applied. I think more predictable results will be achieved...
Not sure if the image will show here as this is my first post with a pic... If it doesn't work, check here for more images: http://s622.photobucket.com/albums/tt302/tszpieg/
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