Some progress this weekend – albeit, as ever, not as much as I’d hoped. After initial and crappy attempts to scratch-build a window frame in place, I applied some science this time and diagrammed the thing up in Visio to scale. This gave me precise measurements and angles which, with my new mitre saw, were a breeze to cut.
Using some newly-delivered 18×96 planed strips, I cut out the pieces for the bottom and sides of the window. The top pieces will wait until the frame is in place so they can be measured accurately. I’m expecting a slight degree of variation in the lengths due to previous bodging. Once the pieces were cut, I screwed them together – I could have gone for mitred frame cuts and glued the nailed them together, but flat joints are easier to work with in this case. Two long (50mm) screws in each joint, deep into the joined board. This gives the joint a high degree of stability (but not so much that it won’t sag, so supports are the order of the day).
A pillar goes in at the very front of the window to support it at the mid-point, and the frame is screwed down into that to keep it there, while the sides of the windows are screwed together to join the individual pieces, and then into the a-frame at the rear on each side to anchor it. Job done.
Once the top pieces are done and in place, the structure will be rather more rigid, and then another supporting pillar will go from the top of the window frame up to the top of the a-frame behind it to provide an overhead support and complete the structure. For now, it looks like this:
Note that the centre post is higher than the side posts – this is because the front windows have an upward slope at the top to ensure a reasonable forward view. The side windows are rather smaller than you’d find on a bigger jet, but large enough that a 24″ LCD will fit over one to provide a side view. The angle of the side-front posts is also quite severe – 45 degrees to the side-line (53 degrees overall). In hindsight I wish I had made it less so, but at this point I’m not about to start changing it.
Once I have the frame complete I will need to go around it with wood filler for a few small gaps, and then the whole structure will come off in one piece for painting. I will measure the shape and size of the inside of each window for the glass (well, perspex) which will fill it; this will be fitted using some kind of wooden bead, probably a simple moulding with appropriate mitres. Two vertical support posts of 44×96 mm baton will go in under the corner of each side window, to support the frame and also provide an attachment point for the framing which will define the MIP and glareshield.
With this in place, you can start to see a little more of a cockpit and less of a random collection of wooden bits. But there’s a long, long way to go yet.