It is now January, 2019. Progress has been glacial, but ongoing. Last entry was beginning work on the wing to settle some alignment questions with the fuselage and control cables.
I built a simple table to work on the wings. I leveled one end and used diagonal crossing strings to align the other end. I had the new spars alodined at a place in Minneapolis that does light poles and large pieces of architectural trim.
You can see the " table" in the left side of the picture here, supporting the spars. Just a piece of plywood screwed to the legs. A piece of osb ties the other end to this one.
I followed the wing assembly procedures that came with the Dakota Cub rib STC.
Dakota Cub listed the location for the ribs in their procedures. The installation of their fuel tanks requires moving some ribs and compression struts and installing a brace tube in the tank bay.
I ran into an interference issue with the tank and compression strut just outboard of the tank bay.
The new strut supplied with the tank kit uses bolts to hold it together. The original Piper used rivets. I took the bolts out of the strut first and turned them around so the head was toward the tank (this picture) but still, I wanted more space. I replaced this strut with the one from the end of the wing (original Piper) and resolved the problem.
I am using the Sullivan STC for flap installation. There are a number of issues related to the drawings and dimensions for this STC. The issues have been discussed many times on this site.
I assembled the flap hinges and aileron hinges and hung the flap and aileron to see how different the issue would be on this plane. I used super glue to temporarily fasten the bellcrank bracket to tape I put on the spar.
I established where the control cables entered the wing and made a cardboard template I taped to the root rib.
The green strings are the routing for the aileron controls and the orange electrical wire is where the flap control winds up. There were also issues regarding the strap locations for
the fuel tank supports. The one you see here (green) has to miss the bellcrank bracket and the wing root attach bracket on the forward spar.
I played around with moving the bellcrank up and down a bit.
I used a small piece of baling wire to see how far I would need to deflect the control cables to clear the flap pushrod and bellcrank.
I also had to move the rib outboard about one inch to clear the bellcrank. If the bellcrank is moved lower than it is in the right most picture above, it contacts the flap hinge arm instead of the stop.
At this time, the hole is drilled for the flap hinge bracket. NOT where the STC calls out, but the spar print from the Northland cd.
Still have to get a location for the flap return springs. Think it is Mike S. who recommends two springs on each flap.
One of the newer flap STC diagrams shows a bracket used to keep the aileron balance cable off the flap pushrod. Many folks here argue that is a high drag and wear point for the cable. I agree.
I plan on using a small pulley to divert the cable. The pulley will mount to the rib adjacent to the bellcrank.
Happy new year all!
Wayne