BYYB Forums

After two days of epoxy-ing, I'm almost happy with the finish. The 10 oz cloth really takes a lot to fill it.  I bought a 4.5 gallon kit and I'm not 100% certain that I will have enough to finish the inside without buying another gallon. [fingers crossed].  So far I've avoided any major runs, which may be related to why I'm on coat number 5 now.  I'm probably being too stingy with my coats, but I have zero drips!  Here are some pics-

This was clean a few pics ago!


After coat #3 (I think)




Going to have to fair in that line where the fiberglass overlap ends (on the left)


I did find a few spots where the glass did not lie down all the way, mostly small bubbles.  You can see one or two in this pic.  I plan on drilling and filling, or grinding and filling these after I've finished coating.  I think the Dremel tool will come in handy for that part.


Stupid fly...



Novel shot of the bottom


Bubbles...

If you're going to paint the bottom of the hull, don't waste straight epoxy trying to fill the weave. Use a light weight fairing compound. The System Three QuickFair is good, though kind of expensive. It's smooth and buttery. I mix my own usually, using q-cells, talc and silica below the waterline and balloons, talc and silica above.

The bright finished area, well it just takes coat after coat until it's filled. A foam roller work good for applying resin in a uniform, even thickness. A brush is the worst thing to use.

One coat with the fairing compound will usually fill 90% of the weave and then it's just touch ups and fixing low spots. A lot less epoxy use, that's for sure.

4.5 gallons of goo is a lot on that size boat. I used 5 on a 17' partly decked boat recently. You have to be eating some of it. Come on you can fess up, it's first stage of admitting you have a problem.

I have at least a dozen epoxy pucks lying around the shop.  Little round disks ranging from 2" to 4" in diameter and 1/4" to 2" thick.  They were made from left over epoxy and epoxy with fillers goo.  I'd regularly mix a bit more then needed.  After a while I noticed my pucks were getting thinner and eventually they became just thin pieces of plastic glass as I got more proficient.

I probably used twice the epoxy needed for a boat the size I built because of waste and because I insisted on double or triple coating surfaces that gained little from the extra thickness.  In my mind the extra thickness translated into durability but I doubt that is the case.  I also made the mistake of filling weave with clear epoxy on surfaces I later painted.  It took 6 coats of epoxy to fill the weave on the hull.  Compare that to 3 coats on the deck surfaces.  I shitched methods after reading one of Paul's posts on using epoxy bondo and bought some micro balloons.  Since each coat on the deck was probably a pint or more of epoxy the savings adds up.

Over the years of epoxy use, I'm now at a point where I can guess quite accurately how much goo I need. I constantly amaze myself at how accurate I can get with this. You too will and have learned quite a bit. One rule of thumb is, it takes about as many ounces of goo to wetout as many ounces of cloth. So, if you're laying a couple square yards of 10 ounce, you'll need 20 ounces of goo. The same is true of raw wood (softwoods anyway). I use a slightly different method than most and I call it the smash and scrape technique.

In Florida, out gassing is a real problem so to avoid this, I spread out the epoxy on a piece of plywood (for example) then I use a squeegee or putty knife to smash the goo into the surface, as I drag the blade across it. If there's excess, it scrape it to a dry location and continue smashing it in. The idea is to force the resin into the wood fibers, but not have any pools of goo on the surface where bubbles can form. Instead of having a wholly shinny surface when I'm done with the first coat, it's uniformly satin, with occasional drier looking spots. If the wood out gases, they rise to the naked surface and vent, rather than get stuck in a surface film. The next coat that goes down is a different story and I use a roller, to apply a uniformly thick coating. This is when I'm shooting for a shinny surface, as the fibers have already been sealed. I find I use less goo with this technique, while still getting good results.

Fairing coat is on.  Found a lot of low spots doing this.  Will sand off the excess tomorrow. 

Strip planking always seems to require more fairing then other methods. I find a 10" or 12" drywall knife useful in the first fairing coats. Identify your lows with a long board and a light "scratching" up and back down the hull. Mark them and fill with light weight compound. This is where the drywall knife comes in handy. You can apply a uniform thickness of goo, while bridging the lows with the knife.

I'm thinking about changing my signature to " You know it's perfect when whatever you're doing to fix it is only making things worse."

Last fairing coat is done.  Added one thin coat of epoxy to fill in any open glass bubbles in the filler.  Gonna paint in a week or two (give all the 'poxy time to cure 100%).  Too shy to post pics.  You'll just have to trust me that it looks pristine.

Will, if at all possible get some serious temperature in the shop or around the boat. What I do is tent the boat with a tarp, then install a heater or two, so I can jack the temperatures into the low 100's for a day. 120 to 130 would be ideal, but most heaters available to the public have thermal trips and the heater would just shut off. I have 4 electric heaters that look sort of like modernized hot water heater radiators. They're oil filled and have a thermostat. The thermostat shut them off around 110, so I removed them and wired a thermostatically controlled switch, which I set at 130.

The poor man's way is to drag her outside, into full sun and toss a black tarp over her for a day or two.

The point is to post cure the epoxy, so the last little bit of shrinkage occurs now, before paint. This will force the weave to show, but can be filled with high build primer. I use a lot of primer, several coats, as I fine tune the surface. It'll take 4 coats just to get 2, because you sand off 50% or more as you're blocking, filling, smoothing, etc. Use different color primers. You can use the same primer, just add some pigment to some of it. If it's oil based, just add an oil based paint or pigment, water based the same deal. This way when you sand, you'll see the layers you've "rubbed" through, making smoothing and fairing much easier.

Greetings Paul,

Two questions come to mind.

If you did not post cure the epoxy with heat to allow quick follow on painting, just how much time would have to pass for the epoxy to fully cure on its own, chemically. A week? A month?

And secondly, if you were using Marinepoxy with the slow hardener, just how cold can the shop get before the epoxy fails to go off? 50°F? 40°F? 35°F?

Thanks,
Tom