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Re: Strip: Milky finish
In Response To: Re: Strip: Milky finish ()

The amount of variables between what we agree on with words and do as deeds is vast.

I continue to learn with every build. On my last build I wanted to add another epoxy coating. And now I can’t remember excactly what I did, but it should have been to wash the surface with a scrub pad and water. Wipe with a paper towel dry and coat with epoxy.

For some reason I wiped with a wet sponge and let pooling water dry, so I had water spots on the resin surface. Added the epoxy coat, sanded and varnished, it looked great. BUT in full sun from a certain angle you can see those water spots!!!

Several things you said you did, would be on my no list.

You brought the shop temperature up but didn’t say how long it was at temperature before it started to drop, did it start to drop? Before coating? The temperature swing of your thermometer will not be a good indicator of the temperature of your hull and glass. Off gassing of the wood could have been one issue.

While having warm resin is good, because it will wet-out the cloth thoroughly, if the boat, glass and shop are not at that same temperature the thin coating of epoxy spread on the boat will quickly drop in temperature and thicken. Slow thick resin has no advantage in wetting out fiberglass cloth.

You also mentioned that 3 batches of resin were enough to coat your whole boat. That sounds like large batches of resin to me.

Resin starts to thicken the moment you add hardener, even slow. The bigger the batch the faster the “musical chairs” dance proceeds. I’ve had the experience of going to coat an area and I had some other parts to coat first and I got careless about time and when I was rolling resin on a surface I realized how sticky the roller felt, oops! A large batch means less work time.

I never mix more than 6 oz. total.

I’m not fond of the squeegee application method because it promotes the use of large batches of resin, poured onto cloth, which makes the cloth float on the pool of resin that goes right through the dry cloth and then the squeegee forces the resin through the dry cloth creating foam.

Resins are very different. You can’t know this unless you’ve tried a few different brands which I have. MAS low viscosity resin with slow hardener will cure tack free in three hours @ 80˚. System Three general purpose resin with slow hardener will cure to a tack free stage after eight hours @ 85˚. That's a BIG difference in how long bubbles, foam and cloth can interact with thin resin.

Clearly one can use bigger batches of resin, lower temperatures and squeegee application and have good results. Nick seems to work this way.

However, I believe the window for success is smaller using those methods. If you control all your variables closely each time, perhaps it works. On the other hand I like to look at each variable, see how to maximize the success rate for each and put together a method which gives me a bigger window of success with unexpected variables.

This is what I’ve come up with, -

So do you live with it or not? You can just say the devil was at work and let your wife paddle in shame, or you can get rid of that nasty glass and start over.

Sound too rad? Ask Nick. It takes a lot less energy and time to fix it, than to fret it.

I dyed a hull bright red one day. I came in the shop the next day and couldn't believe what was I thinking!!!!

Sanded all the dye off in an hour and that boat had these cool little red highlights all over. Removing glass and sanding away the dye will not take long. And you will have a new sense of "JUST FIX IT!". Put that on a T-Shirt.

All the best,
Rob Macks
Laughing Loon Custom Canoes & Kayaks

“Persistent people begin their success where others end in failures.” - Edward Eggleston