 |
This picture shows the process of making the flox "saddle" for the canard. After putting electrical tape to avoid gluing the canard to the fuselage and the lift tabs to the fuselage, I applied a layer of flox between the fuselage and the canard and let it set. I then tried to remove the canard and found that it was really stuck to the fuselage despite the use of the electrical tape. Amazing how well flox can bond to what you don't want it to bond to. (my english teacher would be horrified, ending a sentence with a preposition) In the end, I gritted my teeth, gave the canard a few good knocks with a hammer (I used a piece of wood between the hammer and the canard) which popped it right off. |
 |
Another photo showing the electrical tape everywhere. |
 |
A closeup of the same. |
 |
I forget whether this was before or after. |
 |
The canard is in place and I have my jig to verify that the angle of attack is still as it should be. |
 |
Another picture of the canard in place. At the left, you can see the angle of attack jig to ensure that I have not put any twist into the canard. |
 |
Unfortunately, not everything
was perfect. I have a gap of about 0.35 inches (about 8 or 9 mm).
Stangely enough, this corresponds exactly to the amount by which I
moved the F28 bulkhead backwards based upon the comments found in the
FAQ. I wish I had left it as specified in the plans. Later on, Wayne
Hicks pointed out that this confusion comes from whether you measure
from the front or back of the F22 bulkhead and whether or not you
include the doubler when you talke about the "back" of the F22
bulkhead. In the end, I will have to do a little work for the rear
alignment tabs. I decided to add triangular doubler to the front of the
alignment tabs to extend them so that they can sit properly on the
trailing edge of the canard. I don't believe that there will be a
problem with strength because the loading is quite low* and we have at
least 5 layers of fiberglass reinforcement. * if we assume that the canard supports about 400 pounds withe 80% or so being held by the front lift tabs which are very near the aerodynamic center of pressure, we can see that each of the rear tabs will see about 40 lbs of static force. If we ever pull 6Gs, that still is less than 300 pounds which is relatively light loading for 5 plies of fiberglass. Of course, this "analysis" doesn't include dynamic forces associated with changing the elevator position |
 |
Another view of the gap. |
