I may or may not have mentioned before that KrisDi and I were taking the Catholic church’s pre-Cana classes (pre-marital counseling). A couple weeks ago, the host couple gave us a candle and told us to “decorate it in a way that is meaningful” to us as a couple.
Such an open-ended assignment is never a good idea when you’re dealing with engineers.
As you may or may not know (but you probably do), KrisDi and I met working on the Rolling Airframe Missile system, and we worked on that system for about three years before moving up to the Seattle area. Consequently, the RAM missile launcher is meaningful to us as a couple. And that was all we could think of.
This design occurred to me almost immediately after after the assignment (sans actual measurements, of course). You might want to zoom in on the picture if you have a low resolution monitor.
The two things about this design that I really love:
1. The guide/candle is mounted on “stub-shafts” and mounting plates modeled after the way the real missile launcher is mounted on the trunnion arms. The total width of the candle, mounting plates, and stub shafts is greater than the space between the trunnion arms — the additional space is the “socket” drilled into the trunnion arms. Consequently, we had to install the candle/guide and surrounding parts within the trunnion arms before affixing the arms to the rotating plate.
2. The rotating plate’s diameter is greater than the shortest distance between the “garden stakes” that make up a “retaining lip” of the stand, so you cannot lift the launcher off the stand. To assemble it, we had to install three of the four sides on the stand, slide the fully-assembled guide/trunnion arms/rotating plate into place, and then jam the fourth side in.
A few interesting things about our candle:
1. The guide/candle rotates freely in the vertical plane.
2. The trunnion arm/plate rotates freely in the horizontal plane (we used a layer of wax paper taped to the bottom of the plate and the top of the stand to reduce friction).
3. The counterweight which balances the guide (so that it will hold different different positions) is actually a spare part from the systems we used to work on.
4. I didn’t have short enough screws to to stick the garden stake “retaining lip” pieces on top of the 1/2″x1/2″ pieces, so I used vise grips and an industrial wire cutter to shorten the ones I did have.
5. I had to pre-drill and countersink for most of the screws because the wood was too delicate to compress for the screw heads.