Monday, February 28, 2005
Sunday, February 27, 2005
Yesterday we did the final gluing of the stringers, and so far this is the part that I'm most concerned about. We butt-joined the wider piece on the left to the narrow piece on the right. The now-joined stringer runs from the bow transom to the stern transom, and form the entire bow-to-stern frame pieces.
My concern is that that we'll break this specific joint in the period between when the joint dries and when we actually mount the pieces. I'd highly recommend using a two-person moving method with these completed pieces. Set the stringers vertical (so they're facing the way they will face when finally installed). Have one person lift with one hand on either side of the joint in this picture, and one person lift toward the back of the narrow section. I may do another video on this to more efficiently demonstrate what I'm talking about.
But I'm digressing...
Let's assume this joint is as strong as I'd hope it should be... let's concentrate on what we did to set this butt joint... As usual, saturate all of the surfaces to be joined with unthickened epoxy, and saturate the fiberglass tape. Lay a coat of thickened epoxy on butt joints. Lay the plastic on the floor. Lay the bottom piece of fiberglass tape roughly where you want it. Set the boards on top of the bottom piece of fiberglass tape, and preset the butt joint. Lay the top piece of fiberglass tape on top of the plywood butt joint. Lay a piece of plastic on top of all of this. Use a square to get a precise 90 degree angle, as the picture hints at. Then use a piece of scrap wood, and temporarily screw the scrap wood to both sides of the butt joint. This will help keep the butt joint from floating during the curing process.
Remember, if you click on the picture, you can see the picture complete with comments and tags on the pics that can help you visualize what I'm discussing. Again, the picture is courtesy of www.flickr.com
Greg is a Mechanical Engineer, and loves to design and build things. He's been that way for as long as I've known him. I've always liked building things too, but I've never had quite the knack that Greg has for complex projects. Once I can conceptualize the basic process of a task, I can frequently find ways to improve or streamline an existing process, but Greg is the visionary. (I'm great at reverse engineering.) So Greg's desire to design/ build and my desire to see the inner workings (how does this work, and how can I make it work better?) is the other major driving force.
And of course there's the friendship factor... hanging out with a friend, drinking a few beers. But I've already covered that aspect in another post.
Tuesday, February 15, 2005
In this picture, you see several sheets of plywood joined together to form the length of the hull. I am standing directly behind the starboard bottom piece. The starboard side piece is the other section that's laid out. Here's what we did...
We test-fit the sections end-to-end. Once we were satisfied that the pieces fit, we put the sealer coat of epoxy on each side of each butt joint. Next, we joined the pieces together.
In order to join the pieces together, we started with a huge sheet of plastic on the floor (epoxy won't stick to the plastic), then we set a thin strip of plywood on top of the plastic (you'll see the method to our madness in a minute), then we laid down another strip of plastic (again, because the epoxy won't stick to the plastic).
Next came the lower strip of fiberglass tape, measured just longer than the butt joints, and placed so the tape fit roughly equally on each piece of plywood to be joined together. We next carefully set the plywood in place.
Next came the top piece of fiberglass tape, again set so that the tape sits equally on either side of the butt joint. Next came another plastic sheet (for non-stick purposes), and finally, another thin strip of plywood.
After all of this was set in place, we double-checked everything and ran a screw through the whole shit-n-shebang, ensuring a non-slipping, tight, solid butt joint. We repeated this whole process for each butt joint. There was a lot of prep work involved, but it saves a lot of work in the long run. We used any leftover epoxy to seal the plywood; we'll finish the sealing process before we lay the fiberglass over the whole hull.
In summary... we sealed the plywood underneath the fiberglass tape with epoxy. We laid down the big sheet of plastic, so the plywood wouldn't stick to the floor. We laid down a piece of scrap plywood, so the screws would have something to sink into. We laid down a strip of plastic slightly bigger than the scrap plywood. We laid down the bottom epoxy strip. We set the plywood in place over the lower piece of tape. We laid down the top strip of fiberglass tape. We laid down another piece of plastic. We set a top piece of scrap plywood on top, and ran a screw through all of it. Once the butt joints were set, we removed the screws.
Monday, February 14, 2005
It's an unfortunate reality that I feel the need to post this disclaimer, but I don't want any of your silly asses filing a lawsuit against us, saying "Greg and Dave made me do it." We didn't make you do anything!
Video of the epoxy tray we made
Mixing the epoxy
Applying the epoxy sealer coat
Mixing the thickened epoxy (Peanut Butter)
Be careful after you lay the epoxy
After laying the sealer coat of unthickened epoxy to each surface to be glued, lay the thickened epoxy on one of the sealed surfaces with a trowel. After the thickened epoxy is applied, set the pieces together, weigh them down to ensure a good solid bond between the surfaces, and apply a couple of screws to hold the surfaces together. We specifically recommend the weighting and screwing process, as if you don't weight them down, you may not get a nice tight fit. If you don't screw the pieces together, the epoxy can act as a lubricant between the fitted pieces between when the surfaces are laid together, and when the epoxy sets. The result is that you can end up with the pieces sliding a little, and the fit of the boards is not as precise. You can remove the screws after the epoxy has dried.
Sunday, February 13, 2005
Quick Video Synopsis of events to date
In the end, Greg bought a set of plans for a GT23 GT cruiser. These and other plans can be found at www.bateau.com
Once the plans were purchased, he had to decide whether to cut the wood himself, using the plans as a guideline, or to order a kit from the Internet,in order to save a LOT of time cutting out the raw pieces. Greg ordered the kit from the same site.
Stay tuned for further developments.
Friday, February 11, 2005
Realizing in advance that this would be a long process, Greg and I decided that we would design and implement as many labor-saving devices as we could early on. This photo shows a jig we built to save time, labor and materials as we use epoxy and fiberglass tape to join the various seams together.
The tray, located on the left side of the shelf unit, is designed for saturating the fiberglass tape with epoxy before laying the tape onto the plywood joints. Located close to the tray, are two rolls of biaxial fiberglass tape on a metal dowel. A tape-measure is also attached to the shelf, for quickly and accurately measuring strips of the fiberglass tape.
This process allows us to quickly and efficiently measure out strips of fiberglass tape, lay it in the tray, pour epoxy into the tray, and squeegee the epoxy over the fiberglass tape, giving an even coat of epoxy, and making sure there's neither too much nor too little epoxy on the fiberglass tape, which helps ensure a strong joint.
If you click on the picture, you will be taken to a larger version of this picture, complete with comments and notes. (Larger picture, comments and notes courtesy of the features of www.flickr.com -- a great site for posting, commenting on, and blogging photos.)
Over the summer, Greg decided that he wanted to build a houseboat. After months of research, he finally bought the plans and kit for the houseboat of his dreams. Knowing full well what I was getting myself into, I volunteered to help him on this project, which will probably take 18-24 months to complete. He's buying the beer and giving me a set of keys to the boat when it's finished, so it's not like I'm doing this completely for free. But the real reason I'm helping is because he's my best friend... I've known him for almost 25 years.
This blog is mainly designed as a way of documenting what we're doing as we build Greg's boat, but I suspect it will also be a blog about drinking beer, the stress we experience along the way, and probably about friendship in general. Stay tuned for future developments.