After making the canard cutout in the fuselage sides down to the top of the canard bulkhead, set the canard in place and fine tune the alignment (centered, level, incidence, tips equidistant from the ends of the CS spar).  Since this will usually be done before the reinforcing triax from the canard bulkhead to fuselage is installed, space the mounting tabs away from the bulkhead with two thickness' of stirring sticks (a.k.a., tongue depressors).

Since there is likely to be some mismatch between the canard bulkhead and the canard, align it so at least one of the tabs is against the bulkhead (plus the two sticks), and at least one side flush with the top of the bulkhead. When it's all lined up, remove the canard and put some microglass in the "saddle" on the fuselage sides; put release tape on the canard and set firmly in place.  Double check alignment.  You might also at this time like to use some micro to form a nice fillet between the underside of the canard and the fuselage.  Once this saddle has cured your canard alignment is set by just setting it in.  Before removing the canard, mark (or drill) the 1/4" pilot holes for the mounting bushings centered in the holes on canard mounting tabs.

With the top of the fuselage on, triax reinforcements installed and trimmed to the canard saddle, drill out the 1" holes for the canard mounting bushings.  Sand the microglass "saddles" and finish with one ply of fine BID.  Put the canard in place and insure that the bolts will go through the mounting tabs and bushings.  Also note if any wide area washers are needed to shim between one of the tabs and the bulkhead.  Remove the canard and ream out the holes as necessary.

In order to get the bushings exactly aligned with the canard sitting nicely aligned in its "saddle"; put the microglassed bushing in just flush with the front side of the canard bulkhead, making sure that any space around the bushings in the bulkhead is filled with microglass.  Put the canard in place; get any washers needed between the tab and bushing into place, and put the bolts through (being careful, of course, to not push the bushings out).  Put the nuts on (with suitable spacers if your using the lock nuts) and snug them up.  This will pull the bushings against and square with the tabs (and/or washers).  Let it cure. You'll want to do this before putting the "doghouse" on, especially if you don't have the RBH.

Rather than grind down the bushings to be flush at the back of the bulkhead, you can sand one side of the wide area washer and fill any space between the washer and bulkhead with microglass; bonding the washer in place.  Be careful not to get microglass between the washer and the bushing. You can do the same for any spacer washers needed in front of the bulkhead.  Use the bolts to hold them snugly in place while the micro cures.  This gives good bearing area on the bulkhead and you don't have to handle any washers when removing and installing the canard.

For the torque mounts at the back of the canard, lay up the triax tabs onto the canard as described in the manual.  Let them cure.  Now put the canard in place and slip the bolts in the mounting bushings to insure alignment.  Working from inside the fuselage (sorry, the panel can't be in to do this) bondo in a couple of 10" long pieces of 1 x 4 below and flush with the back of the triax tabs on the canard.  This can be done easily by clamping a small piece of plywood (or similar flat stock) to the tab and to the piece of board to hold it in place while putting on the bondo.  Tape off the board and tab so you can do the prescribed layups right onto the back of tabs and onto the fuselage (see photo 1).  Let cure, drill for the 1/4" mounting bolts, and shape the tabs (see photo 2).

Now all the mounting points will match up exactly.  No spacers, no play, no stress due to misalignment.

Back to AIRPLANE