As a day job (when I'm not in my cape and mask by night as THUNDER-EGG MAN), I'm a mild-mannered land surveyor. So, the task of laying out the profile and door was right up my alley. Instead of fiddling with the base geometry (particularly since many of the curve centres are a long way off the trailer edge) I opted to cut the template sheet to a known size and pull offsets at even inches, like so:
Worked like a hot damn. It's not as tedious as you'd think. I worked in millimetres like a good Canadian ... even so, you can see some effect of rounding errors in shallow parts of the line. I don't think it will cause a problem: I'll cut it a big big and sand to the line, so that will let me "BS" the very small errors out. Here's the layout in full swing. I even tested out the camping lantern when the power went out:
"Hang on!" a voice in the mob shouts. "I thought this was a quality product we're building here! That's just boring old standard plywood!"
Not so fast, sir. This is merely the template! All 4 wall skins (2 inner and 2 outer) use this as a guide. No need for repeated measuring, cutting and sanding. Naturally, they're all fashioned from the highest quality Baltic Birch.
* Crowd murmurs abashedly, shuffles feet *
And here's a fine-looking door, whose shape I'm still warming up to. There are three outlines here: one for the hole, one for the outer skin, and one for the inner skin, which is smaller to make room for a seal system:
I've got this arranged along the wall of the garage, so I can work on it whenever I have the time. Cutting and sanding to taste won't make too much dust, so getting this tuned up will be a nice little mid-week project.
After it's done being a guide and mentor, the template will get chopped up and used to make spars, ribs, and various internal supporting members. Shows what respect our society pays our elders.