June 24th I got out flying, finally, after quite a hiatus due to inclement weather. The days events didn’t go as planned to say the least. The following is an account of what happened that day after I had some time to organize my thoughts and go over things in my head.
When I first arrived my engine woes continued… or perhaps more specifically to start it was prop/spinner woes. My previous time out the engine backfired and sent the prop, spinner, nutt & washer flying (without the aircraft! :S). On my 4 Star 60 at this time is the second hand engine I bought for my Aero 3D, the same as the original engine on this aircraft, a Saito 100. The original engine is awaiting a full diagnostic and a parts list to be ordered and replaced.
Early last week Peter was over and we sanded the previous application of filler. Then thursday mixed up another batch of filler and did some, hopefully, final touch-ups in a short session preparing for covering. This included the leading edge touch up in the bottom image. In that image you can also see some wires, the smaller one with the ends bent in the same direction is the piece of wire for connecting the two elevators.
Today, seen in the featured image, we worked on the leading edge. For this cut a 4″ 3/32” balsa sheet in half (length wise) and then marked the center at the edges after cutting it length wise to fit from the edge of the WC assembly to the the end of the leading edge and repeated for the other sheet.
Next, I soaked the piece of balsa with hot water and pinned it in place while Peter folded it over and held it in place. Started by pinning down the center line and then the edges. Once that was done realized needed some additional help to keep the shape and duct taped it down. You can see how we left it to dry in the featured image above.
Thursday, Peter brought over his epoxy and filler powder so I could mix up a batch and smoothen out the surfaces on the bottom of the wing.
First, finished sanding the W-ST-2’s to be as flush as we could to the W-SH-6 sheet. Then using a popsical stick I applied the filler thick and Peter smoothed it out with a plastic smoothing tool. This process was repeated multiple times to get the following key areas:
Sheets meet the bottom of the wing
W-ST-2s meet W-SH-6
Edges of WC where the W-SH-6 sheet and W-ST-2s should meet to smooth it out
Various other areas on the bottom of the wing to fix dips, etc.
You can see the majority in the image below and the WC portion in the featured image at the top. Next step will be to sand it out smooth.
Thursday, utilized the slot machine (motorized hinge slotting machine by Great Planes) to make hinges in the following control surfaces:
I definitely need more practice with this as I always have a tendancy to tilt the machine towards me causing me to come out the side. That said though, made some solid good ones too, but in most cases takes me a second run to get the slot proper.
Due to the angled portion of the elevators I needed to do the hinges up close to the angled part by hand, using an exacto-knife. For this you go straight in and push along the slot, up and out as you need to get the pieces of balsa out of the hole as you go. I trial fit a hinge along the way to avoid over cutting the hinge slot. I also verified previously cut hinges and made adjustments with the knife where necessary.
In the featured image above you can see where I rounded the leading edge of the stabilizer for a nicer, more aerodynamic, look.
You can see the hinged elevators in the top image below and the hinged ailerons in the bottom image below. You can aslo see where I have done some angle sanding along the hinge edge of the elevators to allow the elevators movement once hinged to the stabilizer. I still need to do this to the ailerons along with rounding the trailing edges.
We were looking at doing the rudder and vertical fin too; however, something wasn’t looking right when we were putting the pieces together for a look so need to figure that out first.
Thursday, I got my hands on the hinging tool again, and this time it worked!
Started by verifying the hinge locations and making clear center marking on both the wing and ailerons… verifying we were using the correct aileron for the side we were working with. Once that was done used a centering tool to mark the center line on the trailing edge around the hinges and along the length of the ailerons.
Yesterday I got the the W-ST-2s that I previously made glued and pinned as part of the WC assembly. For this I needed to make sure they sat flush on top of the WE’s (outer pieces of the assembly) and fully covered the angled WC.
To improve the fit I sanded off some of the sides of W-SH-6 at a bit of an angle to get a tighter fit. Wood glue was then applied along the edges, on top fo the WE’s, and in the appropriate spots, including excess on the sides, of the W-ST-2s. Better bonding experience when all pieces that are part of the “gluing experience” contain glue.
Doing one at a time, ensuring everything was in place, started pinning from the back of the wing towards the front, verifying the W-ST-2 remained in place.
You can see how I left things to dry in the featured image above.
Sunday, I continued work on the WC assembly building upon Saturdays success. I started by building the other W-ST-2 (top in image below), which invovled going through the same process as in the previous post and then moved on to the 3/32” balsa sheeting piece W-SH-6.
Saturday, I experiemented with how to build the rounded edge (W-ST-2s) pieces for the WC assembly… which is what I’m calling the group of pieces that congregate around the bolt hole openings on the bottom of the wing.
Wednesday, made some more progress on getting the wing bolting system in place.
First thing was to get the hole locations marked on the wing hold down plate (FUE). Since I already had the holes drilled into the wing I used the 1/4” bit to place through the holes, while the wing was held in place on the fuselage with clamps, to make markings on the hold down plate (FUE). Next, I put the fuselage, with some support, on the drill press and made sure the plate (FUE) was perpendicular to the drill bit (size 5/16“) and drilled the holes.
Once the holes were drilled I filled the T-Nutts with vaseline to ensure no glue got inside and mixed up some 30 minute epoxy, which I applied all along the buttom of the nutt and up the shaft before pushing it (from the bottom) into the previously drilled holes. Used a C-clamp to squeeze the nutt into place. Checking and adjusting the clamp as we went. You can see the result in the featuerd image (top view) and right imge below (bottom view).