The aft flap cover needs a bracket fabricated to attach it to the floor.
Started Flaps
The next step in the plans is to fit the forward tunnel cover, but since that sits against the flap cover, I decided I wanted to install the flaps first to ensure the cover fits as well as possible. First up, I drilled and reamed all three ends of the flap weldment to 1/4″.
Attached Seat Bottom Hinges
The seat backs attach to the seat bottoms with sections of P3 hinge material. There are three pieces of hinge attached to the seat bottom, and one piece attached to the seat back. That along with the adjustment mechanism at the top gives you a number of choices for the seat position. First up, I cut eight pieces of hinge material 15.5″ long.
The six hinge pieces that attach to the seat bottom need the center two eyelets removed so that the hinge pins can be inserted from the middle.
The holes were laid out and drilled on one of the pieces according to the plans. This was then used as a template to drill the other five pieces of hinge.
The hinges were then clamped to the seat bottoms at the position specified by the plans.
The seat bottoms were then match drilled to the hinges.
The aft hinge overlaps several holes that are used to attach the seat bottoms to the seat ribs. The hinge is back drilled to these holes so that all three pieces can be blind riveted together.
The hinge pieces are then riveted to the seat bottom with AN470AD4-4 rivets (skipping the holes that will also rivet in conjunction with the seat ribs). I’ve seen a few builders use LP4-3 here, but the plans only specify those for attaching the seat bottoms to the seat ribs.
Finished Baggage Wall
I positioned and drilled the wear blocks.
Here you can see that the opening in the wear block keeps the stainless steel cable away from the aluminum.
The holes that were match drilled in the lower baggage wall need K1000-08 nutplates installed so that the upper wall can be screwed to the lower wall.
The lower wear block gets blind riveted to the lower wall with a couple of spacers made from 0.040″ AL sheet. I didn’t take a picture, but the upper wear blocks are riveted to the upper wall in the same fashion.
Modified Baggage Wall for Harness Anchor Cable
Primed and Riveted Fuselage Components
Since I’m going to mount the ELT on the Van’s mounting bracket on the right side wall behind F-706, but put the antenna behind the roll bar, I decided to run the antenna cable behind the baggage sidewall. I drilled a couple of 3/8″ holes in F-706 and F-724 below F-786B. The cable will also run behind the flap cover and then come up through F-786B right behind F-705. I then fished a piece of safety wire through both holes so that I can later pull the coax through. This would have been easier to do before riveting on the side walls, but it wasn’t too bad.
Update: I ended up not mounting the ELT on Van’s mounting bracket and put the antenna under the empennage fairing.
Next up, I drilled 3/4″ holes through F-705A and F-706 on both sides of the fuselage and ran conduit. I’ll put a zip tie anchor on the rib and cushion the holes with proseal before buttoning this up.
On the right side, the wires will exit the lower conduit and come up the back of F-706 through an adel clamp to keep them away from the rudder cable. The ELT wires (other than the antenna cable will separate here and go to the ELT bracket. The trim and tail strobe wires will continue up and enter the conduit shown in the upper right which makes a straight shot to the tail. I’ve intentionally left this conduit long right now while I determine how to terminate it.
Here you can see that the conduit passes through F-707, F-708, and F-710. The wire bundle will then separate with the tail strobe wires dropping down to penetrate F-711 and F-712 and into the rudder while the trim servo wires will make their way up and into the elevator. I put the conduit up high like this to keep it about 2′ from the Dynon Skyview ADAHRS unit.
I deburred and primed all of the fuselage components that I’ve finished so far.
After those were dry, I riveted F-709 to the aft deck.
I then riveted the aft deck to the longerons and F-710/F-711. There were four rivets that couldn’t be reached with the squeezer, so I’ll have to shoot/buck those.
Next up, I riveted the F-695 gussets to the longerons and upper firewall stiffener. There were two rivets on each side along the firewall stiffener that couldn’t be reached with the squeezer. I’ll shoot those later.
I then squeezed all of the rivets that tie the bulkhead braces to the longeron.
I squeezed all of the rivets that hold together the elevator bellcrank. I’ll have to slip a washer in between the halves when hooking up the autopilot servo, but that will be easy with the washer wrenches.
I also assembled the hatch in the left baggage floor. Here, I’ve riveted the reinforcing ring and hinge to the floor.
I then riveted the other part of the hinge and the hartwell latches to the hatch. Here is how it looks closed. The hatch closes firmly enough against the flange that it shouldn’t rattle in flight.
And it opens just enough past vertical that it will stay on its own. I’m really happy with how this turned out. This will come in very handy.
Match Drilled AHRS Mount Kit
I ordered the AHRS mounting kit from Van’s. This is designed for the Grand Rapids EFIS or the Garmin G900X, but I’m going to adapt it for the Dynon Skyview ADAHRS. I drilled out two rivets that tied the bottom skins to F-706 and F-707. These will now additionally tie the rib pictured here. I then ensured the ribs were parallel and match drilled the skin to the rib. I then used the digital level to ensure the mounting plate was level laterally and match drilled it to the F-729A rib and F-707 bulkhead. The mounting plate is tipped aft about 0.5º from the level of the longerons, but this is well within Dynon’s 1º limit. I can always shim the ADAHRS unit if necessary.
I’m still trying to decide how to mount the ADAHRS unit to the mounting plate. Dynon calls for nonferrous fasteners, but I haven’t been able to find stainless steel or brass nutplates. I can reach under the front edge of the mounting plate, but I’d kind of like to install the unit near the aft end of the plate in case I want to install another unit just in front of it.
Update: I ended up not installing the ADAHRS here because it is too close to the pitch servo and this can interfere with the magnetometer. I decided to use this to mount the ELT instead.
Ordered Engine
I placed my order for an engine today. I’m going with an AeroSport Power horizontal induction IO-375 with the following configuration:
- 8.0 to 1 compression ratio
- Superior cold air induction system
- Single Lightspeed II+ electronic ignition with direct crank sensor
- Single Slick magneto
- Silver Hawk Ex fuel injection system
- Inverted engine mod (basically some additional internal case machining to better support an inverted oil system).
The stock IO-375 provides 195hp, but the cold air induction system should add 3-4hp. Total price $27,750.
Installed Aft Baggage Side Walls
After vacuuming out all of the metal shavings in the fuselage aft of F-705, I installed the side walls. These use LP4-3 rivets along the top an AN426AD4-4 rivets along the back. After I finish modifying the baggage floors for the hatches, they will rivet to the ribs and the lower flange of this panel.
Worked on Left Baggage Floor
After fabricating the door and cutting holes for the hartwell latches, I test fit the floor in the plane.
Here is a closeup of one of the hartwell latches. They make a crazy number of models of these, but four of the eight I bought off eBay were the same, so I used those.
To open the door, you push in on the button marked “PUSH” (duh)…
and the other part of the latch springs open.
Once both latches are released, the door can be opened. The reinforcing ring provides a lip that the door can be closed against (and the latches catch under).