Bending the control rod was not quite as easy as I thought it would be. Getting it to be
exactly the shape shown in the instructions with the bends
on the same plane turned out to be problematic.
I resorted to fabricating a simple jig after the first couple of tries left bends that were too far apart or not far enough apart or not parallel when viewed straight on.
Next up is assembling the heart of the piston wing-anchoring and deployment mechanism.
I’m guessing this might not be as easy as I think, as the balsa piston will be between the engine block (blue ring) and piston stop (green ring and ply disk) and shoving them in from the bottom and the top respectively will create a glue “dam” ahead of where they’re situated (and be in the path of the piston, which may interfere with its full range of movement). Removing the glue is going to be…well, a challenge since the piston will be in the way and I’ll pretty much be working by braille through the small vent openings.
There’s an engine hook (not shown in the previous pic) that also gets installed after the engine block. To simplify things and deal with the buildup of glue on the piston side where it would be hard to clean up, I decided to reverse the order of things. I dry fit the engine hook then temporarily removed it so that the bent tab thingy wasn’t hanging down inside the tube interfering with things, smeared glue 2.75” up inside from the aft end, replaced the engine hook, then shoved the engine block
down from the forward end (instead of up from the aft end) until it bottomed out against the hook tab. Most of the excess glue glopped up on the
opposite side from the piston, where I could easily reach it and clean it up from the aft end.
A mylar anchor ring neatly finished up the hook installation.
Installing the bulkhead (piston stop) comes next, and here’s where the instructions get confusing. They specify that the bulkhead should be 0.75” from the forward end of the tube, but that’s way beyond where the control rod would hit the forward edge of both the top and bottom vent holes (I’ll try to remember to snap a pic once the engine pod is assembled. It’ll make much more sense then).
Anyway I put the balsa piston into the tube and slid it forward until the hole for the control rod hit the forward edge of the vent hole, and determined that the bulkhead should actually be 1 1/8” from the front of the engine tube instead.
Cleaning out the piled up glue with a damp Q-tip had to be done quickly before it set. Luckily I have an LED headlamp that’s attached to a headband and with the bright light I could pretty much see where to guide the swab. Patient seems to have survived; this part of the operation went much smoother and easier than I thought it would.
The assembled motor pod with piston installed. At ejection, the piston is forced forward and pulls the control rod out from between the wing notches, releasing them from their folded position to swing out to glide position.