Dick, thank you for your kind compliment about the plane.
The instruments are known as Robart incidence meters. They are available from several sources, Tower perhaps being the easiest to access. If you catch a sale right, you may save a few bucks as well.
I prefer to have at least a pair of them, so I can check two incidences at the same time. for instance, I'll set the wing at 0-0, and while leaving the meter attached to the wing, I'll attach a second one to the engine, and check the thrust line. By having two meters, I can compare between the wing and the thrust line. It let's me know if I've bumped, or accidentally moved the plane, throwing my meters off.
Leaving the meter on the wing, I can move the second meter to the stab and check the incidence there.
When finished, I can be reasonably sure that things are where I want them to be.
Gordan Delaney has found something recently that surprised both of us. He aligned his stab and set the incidence where he wanted it, but after installing the bottom block, he rechecked and found the new block had pulled his stab out of alignment, and was giving him negative stab incidence. He was able to reestablish the incidence he wanted, thus possibly saving a ton of frustration during the trimming stages.
Up until this particular build, neither of us had considered the possibility of an added part causing such a major misalignment.
There are at least two styles of incidence meters available. One uses a spirit bubble, and a meter (Robart), the other uses a laser pointer. I've no experience with the laser pointer, so I prefer the first style.
Making a canopy from a soda bottle is fun, and relatively easy to do. You are limited size wise to what you can get out of a 2 liter bottle, though I have seen some drinks coming in a 3 liter bottle. In any case you're limited by the size of the bottle.
Soda bottles are usually PET plastic, and will tolerate butyrate dope being applied over it, an advantage in my mind.
The first order of business is to make your plug, or mold.
You can use most any material that can withstand some heat. I tend to use some of that hard balsa that I can't use for anything else to carve out the plug. I've found it helpful to make the skirts a bit over sized so I have enough material to trim after the canopy is formed.
Once the plug is sanded smooth and ready, it's time to start the forming process.
Cut the top, or the bottom off the bottle. For me, the shape of the canopy determines whether I cut the top or bottom off, but once that's done, insert your plug (mold), and insert enough filler wood to sort of jam the plug in there, so it won't easily move.
Get out your monokote heat gun, and start shrinking the plastic bottle. It will readily shrink, and in a few minutes, after cooling, remove the filler pieces, and the plug. You're ready to trim your canopy.
From there, it's the same as installing any other canopy.
Topic: Bones Tuetonic (maybe) (Read 10508 times)