Daggerboards, Glassing

Another Layer of Glass on 1st Blank

Posted by Paul

As planned I got a very early start this morning but unfortunately that didn’t translate into a long day working on the boat. It probably should have but I had always planned to have the afternoon off to watch my football team (Carlton) win its first game for the season but I am getting so low on hardener now I don’t think I have enough to finish the next wet out. It would be a huge problem to run out of resin with say a half wet out sheet of glass. I would need to remove it and throw that entire sheet out.

There is a cliché that you learn something new everyday. Yesterday I learnt never to rely on wet glass to defy gravity. If it can get a start to fall, it will. And of course there is the inverse mathematics of the dirtier the floor the more likely the wet glass will fall on it. Today I learnt that at 5am it is quite cold in the shed and that with the shed cold so too are its contents and that cold resin is much thicker than warmer resin. Of course I knew this but from the other side of that equation. In the middle of the summer heat resin is very fluid (remember the drum leak just yesterday from warm days!). What I had not experienced before or if I have I have forgotten it, is how difficult it is to apply really thick resin and how much more of it you end up using for any given job. And how much more difficult it is to pump. I am missing the wall pump (since I started running out of hardener and decanting the resin I have been on the bottle pumps).

First thing I did this morning when I arrived (at 5am!!!) was to clean up the board for any rough areas and dags etc that might make wetting out the next layer harder. I also decided to give the blank a quick sand just to be sure, I am pretty sure the resin is still green but I keyed it anyway as I had a couple of sharp lumps I had to remove as they will result in air bubbles with the next wet layer, so while I was at it I gave the rest a light go over. Then I cleaned the dust off ready to go again.

The I cut the uni to size and shape (for both sides of the dagger). Instead of one big sheet of glass like the first 2 layers, this is a series of small pieces as the threads run across the board and cannot go around the leading edge like the up and down threads can. A nice edge to the cut glass sheets is helpful as the pieces will butt up next to each other. With all the piece cut I started the wet out.

dagger uni ready to wetdagger cross uni wet

As I mentioned, it was still cold at 6am so the resin was hard to pump, mixed as thick as honey and went on the same way. It is a good idea to coat the board with resin first so that the glass cannot move once it is in place. I find it easiest to have the glass in place on the board then fold aside half the piece, wet the board under it and fold the piece of glass back over onto the wet resin, then repeat on the other half of the piece of glass and a bit further under the next piece and then replacing the piece and the next piece up close to each other for a nice clean join and then back to wetting out the top of the first piece before continuing on in that order. As always with uni it is important to give the cloth time to soak up the resin (from both below and above) before adding more thinking it is not wet enough. It takes longer for the resin to soak through with uni and much longer when it is cold and thicker. Having said that it is still very hard to not to end up using more resin than you would usually need and because it is so thick it is hard to squeegee out the excess without upsetting the glass threads but pushing too hard.

Once I had wet out the first side I needed to turn the blank over but remembering what happened yesterday I decided to give the resin a chance to tack off a little more so it wouldn’t fall off. I did a few other things here and there in preparation for the next blank. But being cold it was making the tack off take longer so in the end I just turned it over and kept an close eye on it to be sure it was not falling. It didn’t so I just got on to wet the glass on the other side. Then once I had both sides on I let the dagger spin on the axle again to set vertically.

The next layer of glass is a sealing layer of double bias. Uni is very strong in the direction of the uni but the stress that it can be under means it can be prone to lifting (or splintering) from the jobs it is applied to so to safeguard against this a layer of double bias (with the threads running at 45 and 135 degrees) is applied to hold it all in, and to wrap around the corners. But I am pretty sure I don’t have enough hardener left to wet it all out so it will have to go on later meaning I will have to sand this uni layer. I pretty much would have to anyway as there are a lot of frays and bumps that would have made wet on wet around all of the edges that the uni stops at difficult and result in air bubbles. It is for this reason I didn’t bother to use peel ply, peel ply would not stick neatly for the same reason, it will need sanding anyway.

By now it was about 10.30. I had intended working through until about noon but the prospect of filling the rest of the morning with sanding (that is a constant fill in job and seems never ending) so I decided to have the rest of the day off. I still managed 5 and a half hours.

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