I was told by the magic box, that there would be no rain and 55 degree days and nights. Prime weather for epoxy during the time of the year where broke boat owners, have trouble working on their broke boats. So, I took a circular saw and angle grinder to Pylasteki. (Camera was out of batteries that day, so you'll have to imagine the funky super hydrated balsa wood...)
While I had the grinder out, I faired out some of the high spots in previous months glass work on the port side of the bow. The wind was blowing quite nicely, so I had the pleasure of standing up wind of the dust cloud! I use a flap disc on an angle grinder, to do most of my grinding and sanding. They last almost forever when working fiberglass, but take an artistic touch or your boat will disappear in the dust cloud.
Next, I pulled out a Fein Multimaster with the flat scraper and enjoyed easy removal of the good balsa strips. While it would probably be just fine to leave the firmly attached balsa in place, I figure that replacing everything with new end grain will yield a longer lasting and better quality repair.
If you are wondering what the big deal is about balsa wood: Well, it is used as a stiffener. If you want something stiff, you make it thicker. If you want something light... you make it thinner. If you want both stiff and light, you cut something in half and hold the two pieces as far apart as you can and let the height difference, and rigidity of whats doing the holding apart take over. If the two skins of fiberglass don't move relative to each other, they act like an I-beam. Stiff, light, and strong. Nevertheless, I haven't found the reason why the stuff smells like socks.
The way balsa wood soaks in a little resin... just like celery standing in a puddle of food coloring dyed water. (Probably the best use for celery...) When the resin cures, it has become one with the wood. So in order to get the well adhered, non-stinky balsa off the boat it takes patience, putty knives, chisels... Until the Multimaster was invented. Doing the work of twenty men, it vibrates quickly with a harmonic hum. Where it comes into its own, is that two inch wide ledge that has to be left to give something to fiberglass the top skin back down. Otherwise, one is stuck cleaning it out by hand, step by step... inch by inch...
I am impressed... with this spectacular piece of German engineering.
But all good days must come to pass, on the next:
It rained. I'd like to state for those thinking about boat projects... that filling the holes left by hardware bolted to the deck with caulk works to keep rainwater out. At least until, you've cut a 2 foot wide four foot long hole in the top skin of the deck. I woke up to rain drops pitter pattering against my window... Luckily there is plenty of work to be done, some of it even pays...
With the leaks mostly stopped, I decided to try out the saw on the Fein, and cut out the primary head bonker on Pylasteki. I've performed a partial bulkhead-ectomy on two of the semi-structural bulkheads. The partition between the head and hanging locker are largely removed. Mainly because my shoulders had a habit of getting stuck between them as I walked by. - Insert more deranged blathering here -
The Fein, allows you to flush cut by laying the blade against something smooth and remove anything that stands proud. If you click back to earlier pictures, you'll notice that my jig saw can't do that... and I was forever banging my head on the leftovers.
I like uninterrupted horizontal lines on boats. So the visual in the cabin suits me... it adds a lot of volume so she feels larger!
I had a few minutes, so I fired up the grinder. On previous sections I'd done my beveling after epoxying the top fiberglass skin down. So I've been curious if its any easier to grind the bevels before putting things back together. Fiberglass is like an ogre... err... an onion. It goes together in layers, and thankfully on my boat Pearson alternated between mat (kind of looks like a shag rug woven out of a hairball...) and cloth which has similar pattern to burlap, except it is smooth and less itchy. After resin has been added, and it has time to harden the consistency is that of a bowling ball. All that means, is that when I am grinding, distinct layers appear. I keep the bevel the same angle and width by keeping the layers evenly spaced.
The bevel is required so the new fiberglass does not just bridge the gap and build up a high spot. By grinding down to a knife edge (you can see through the edge!) there are no hard spots to bend and crack. The boat believes it is whole once more. I start with a wide piece of fiberglass and work to skinnier strips alternating corners until I've built up a thickness higher than the surrounding glass. I use biaxial fiberglass, which I cut into strips of various widths. The name changes to "tape" when you start talking about long strips. They sell premade tape by the roll, but cutting custom widths makes for less expense. Biaxial fiberglass has bundles of fibers running on 45 degree angles from each other, rather than 90 degrees. It has two layers of bundles, going on opposite 45's. Rather than being woven together, the fibers are held in place by stitches. All this adds up to mean, that it is one of the lightest, strongest materials to use in fiberglass repair. I do like my overkill!
I worked into the sunset, mixing up epoxy with cabosil. Cabosil is a trade name for Fumed silica powder... it is a bulking agent. So light, that a cardboard box full feels empty. The property which I use it for, is that it makes things thixotropic. If you have ever mixed up cornstarch and water to a thick enough consistency that it acts like a solid... but still almost pours like a liquid, you have played with thixotropic. Cabosil allows epoxy to be mixed up into a putty, that stays where you put it. Put a dab on the ceiling and its not going anywhere. Mix it up thick enough... and its not even going to sag.
Only trouble... its like rock candy after the resin hardens. Take a hunk of epoxy filled with cabosil and smack it with a hammer, and it shatters. So, I use milled glass fiber, tiny strands of fiberglass. It looks like dust, but it makes things very strong.
Once the pot of goo was mixed (takes a while...) I filled that two inch wide gap around the edge of the deck, and edge of the cabin top full... and grabbed my camera.
Such a colorful back drop makes it hard not to wax poetic, even if the topic is dealing with fossilized snot!
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