Things that did not go as planned, things that should be done different and other unexpected stuff.


Essential tools and stuff to start the build that is not mentioned in the manual (at least I did not see it):

  • 2 x #21 Countersink Cutter – 120° to countersink the main spar
  • #40, #30, Countersink Cutters 120°
  • Microstop Countersink Tool to create consistent countersinks
  • DRDT-2 from for the dimpling process
  • Reamers for M4 rivnuts, 3.2mm and 4.1mm rivets
  • and other tools listed on my Amazon shopping list
  • The Milwaukee M12 Rivet Gun for a few rivets and a pneumatic rivet gun (e.g. for the wing)
    sometimes the mandrels don’t come out of the M12 easily which is very time consuming
  • Steel rulers for deburring edges (tip from Evan)


  • The eybolts for the pushrods inside the wings are in the “Finishing Kit”.
  • Do not rivet these two rivets on the bottom skin when mounting the “Lower Wing Stringer”. The bottom root skin will overlap here. You could see it on the plan, but I did not.
  • I would rivet the last row of rivets on the rear spar later. These holes should be used to attach the rear spar to the wing jig.

  • The “rear spar upper skin support channel” should be riveted to the rear spar “after” the rear spar has been riveted to the wing ribs. As you see on the picture, the lower two holes can’t be reached with a rivet gun.


The 4 skin rivets next to the “Rudder Control Bracket” (12) are hard to rivet, when the rudder control bracket is installed. So I omitted “Step 6” in the KAI and installed the bracket after riveting the skin. I would also recommend installing the “Rudder Counterbalance Weight” (2) after putting the rudder skin (14) on instead of doing it in “Step 2”. The “Rudder Counterbalance Weight” adds a lot of weight to a flimsy structure.