Wednesday, November 25, 2009

Gluing down the bottom

After gluing together the hull, I came to several decisions, one of them being that gluing is a pain in the ass.

Yesterday I glued down the bottom, and yes, gluing is still a pain in the ass. So much so, that I swore off building another glue-only boat next time, that I'll take fasteners thank you very much, this sucks!

This morning, when I peeked into the garage at my nemesis glue-job-boat, my heart softened a bit, and I feel a little better. But I came close-- In my mind I saw a big bonfire at one point.

Yesterday I smoothed out the seam between the two bottom pieces, scoured the chinelogs and BH's with a rasp to provide a rough gluing surface, planed the transom flat, and screwed the bottom down in place. This took a while, and I was so concerned getting it on straight that it went on straight, but offset by about 2mm or so. I realized this after I screwed it on. This is not a big problem, there's supposed to be a gap of 90mm between the buttstraps for the daggerboard trunk, and I left 95mm for just this scenario. Storer recommends placing the bottom on with the centerline marks on the inside, to line up with the centerline marks on the BH's. A good idea, but then I would lose out on the markings up top that showed where the edges of the boat were (bottom is overcut by 2omm) and they provided a good guide as to screw placement. A better idea would be to have a centerline on both sides. Needless to say, lots of crawling under the boat and back, and shifting the ply ever so slightly.

Screws were placed every 300mm (lines from lofting) and along the BH's (3 for 1+2, 5 for 3, 4, transom). This was insufficient as you shall see later on.

After the bottom was screwed on I made special note of where I had some larger than normal gaps between the bottom and the sides. In these areas I would apply extra glue. Everything appeared tight and for the most part, everything fit together really well. I was impressed.

Next up, I unscrewed the bow of the boat, lifting it with 2x4's. After pre-coating the chinelogs and bottom with unmixed epoxy (more crawling around under the boat), I applied what I thought was copious amounts of glue, using the ziploc-bag method which I still don't like, but it seemed to make the most amount of sense. Mixing the glue with the silica is still a bear, I still don't know how to judge how much silica to add so I eyeball it until I get the appropriate consistency. This takes time. Then, the application. 3 pumps of resin with 1.5 pumps of hardener covered approximately- maybe- 4 feet. Hardly anything. This was going to take a lot of glue.

I moved down the line, sending the 2x4's down to the stern and gluing and screwing in their wake.

(notice me mixing always mixing more mixing in background with knee pads that didn't come off between 10am and 11pm)

I think I made 3 moves aft, covering large sections at a time. The port bow had a little bit of a gap between the bottom and the side, and needed even more glue. This was going to take a lot of glue, as I mentioned before. This is when I started getting frustrated. When I put too much glue during the BH construction phase, it poured out all over the place and was a giant mess. Now, I was putting large amounts of glue onto the chinelogs and when the bottom came down, nothing. No excess squeezage, nothing. Let me just say this: Gluing the bottom takes a lot more glue than you think it will.

About halfway down, I realized I forgot to line the sides with packing tape to ease clean-up. SOB. So I had glue dripping down around the bow, which means I'll be sanding forever. Out came the packaging tape around the aft sections and the transom. By this time my wonderful wife took pity on me and she applied the glue while I mixed it. This doubled the speed of the operation, since mixing takes a long time-- at 3 pumps of resin per bag, there was a lot of mixing to do. She has a knack for how much glue to apply and when we screwed down her end, a perfect amount squeezed out. Damn.

With all the screws down (she held up the stern bottom and gently lowered it as I screwed it down moving aft), we inspected for a gaps. There were a couple small ones along the chine, and a few gaps that needed more screwed to hold the ply down. I would recommend a screw every 200mm at least, as opposed to every 300mm.

Then we flipped her over:

Hot damn, I have a completed hull (above pics are after the "clean-up" (used loosely)).

Clean-up was a super pain in the ass, by this time a lot of my squeegees were gluey and tacky and my rags were used up and I was running out of mixing cups and no matter how many new gloves I put on, I was sticking to everything. Some glue was firming up nice, which meant a struggle to clean it up as is smeared everywhere. Be ready to spend some serious time bent inside the boat cleaning it up. My glue station aftermath:

This took me a few hours of prep, followed by about 7 hours of gluing/cleaning up. Solo, it was slow going, no doubt.

The bottom is still not done, I have to trim the excess off, which will be another pain because it's covered in rock-hard epoxy, but as far as I'm concerned, the big jobs in this are completed. From now on things can be accomplished in short spurts as opposed to 12hr marathon sessions. Thank goodness. I'm tired.

Did I mention this takes a lot more glue than you may think?

1 comment:

  1. I need to say, Thank You. Thank you for sharing the difficulties along with the successes. Your posts are a big help to me as I progress with my build.

    When all is said and done, you now have an assembled GIS HULL! Congratulations.