As always, progress has been made...but it's not as much as I wanted to make. I had hoped to be a littler farther along than I am, but all things considered, I feel like I'm off to a pretty decent start. I'd be farther along if I simply had more clamps, but I'd need another 50 to make any significant difference in the timeline of this project, so it all kind of is what it is.
The first order of business was fabricating the main block of each window trim set, as all the smaller, auxiliary pieces sort of play off of it. These blocks ultimately need to be about 4" thick, 3-5/8" tall, a hair over 3' long, and have radii of 36-7/8" (lower) and 40-1/2" upper; I chose to make them out of a series of individual parts and pieces to maximize strength.
I started with Douglas Fir 2x6s, and after doing a silly amount of math, cut them to the exact lengths and angles that I needed. The miter saw generally doesn't do a real great job of yielding glue-line cuts, so I rough cut everything with the miter saw and made the final, clean cuts on the table saw. Once those were done, I cut mortises in the ends of the pieces so they could receive a spline or floating tenon, which would be used to join to individual 2x6 pieces together. Then I cut some floating tenons, making sure to orient the grain in the proper direction (perpendicular to the joint, in this instance).
The dry fit went well, as it's not difficult to cut splines that are a hair too loose, or a hair too snug and everything's borderline impossible to get fully seated. For each blank that I needed to make, the thought process was to sandwich a 3-piece segment between 2-piece segments, which would ensure that the joints were staggered and provide a rock solid base that the bent laminations going on the upper and lower sides of the main block wouldn't be able to pull on and deform.
Getting the things glued up individually was a time consuming process. Ideally, the best way to clamp a joint is by applying force perpendicular to the joint, but with angled joints this can something be a challenge. To overcome the challenge of the angled joint, I added some little temporary blocks to each piece in order for the clamps to have something to grab onto. That said, having another 10 or so bar clamps would have made a huge difference; as it was, I could only glue up 5 2- and 3- piece segments at a time.
When those had dried, I went ahead and glued the 2-piece segments between the 3-piece segments giving me 5 blanks. When those had dried, I started working on cutting the upper and lower radii.
As I mentioned previously, those radii really do need to be dead on or - my absolute biggest fear with this project - the things won't hug the window like everybody wants them to. That means every cut, every everything, needs to be pretty much perfect. In those instances, drawing a big fuzzy pencil line and trying to follow that with a bandsaw is no good, so instead I opted for the tried-and-true blue tape and razor blade method.
I started by making a couple quick and dirty wooden compasses of sorts. They're nothing more than a couple scraps I had, with a hole in one end so they can pivot on a nail, and then from that nail I measured and cut the scraps to the exact length - or radius - that I needed. I used that to first draw a pencil line where I needed to cut, then laid down blue tape over that, and repeated the process except instead of marking a line with a pencil, I scored the tape with a razor blade. By removing the tape on the outside of the cut, I was left with a very crisp, very clear line to follow.
The next step will be to cut those just a hair proud of the tape line, although I have my doubts about using my current arsenal of bandsaw blades so I'll probably have to go get a new one. Cutting through 4" thick anything is a tall order for my little bandsaw; it'll do it, but it sure helps if everything is as crisp and clean and sharp as possible. After that, I think I'll probably slop together a router jig - sort of a bigger version of the compasses I made for laying out the radii - so I can pivot the router off that same nail and get those curves cut super cleanly and smoothly.
Once the radii are finish cut, I can start preliminarily bending the pieces I'll use for the bent laminations. The plan is to soak the thin strips I'll need to cut in hot water for a few hours, then bend them into shape without any glue. Once they dry, I can then disassemble everything, do any sanding or clean up that's necessary and then repeat the assembly process, and add (a boatload of) glue.
After all that's done, I get to fabricate some ogee-profiled trim. I definitely have a lot of work left on these, but getting the main blocks close to knocked out has me feeling pretty good about how to rest of this job'll go...