Wednesday Peter came over and we got to work on the aircraft. I replaced the defunct far right rib of the horizontal stabilizer (image above) with a new one. We then marked a center line on the trailing egdge and rib so that when we placed the rib back we knew its positioning.
We then got to work gluing all the ribs into place as well as the two end pieces. Once that was done, and ribs were pinned in place, placement for the hinges were marked across the elevator and trailing edge of the stabilizer. We also glued some 1/2” balsa blocks behind the elevators leading edge where the hinges are going to be for added support. You can see these, along with the glued ribs, in the featured image at the top. There will be 6 hinges total, 3 on each side.
Yesterday evening I did some work on my aircraft for about an hour after I got home, prior to getting supper.
I started by cutting out the ribs for the stabilizer… I guess technically I should be calling this the horizontal stabilizer as what I’ve been calling the fin is probably more properly known as the vertical stabilizer :).
Once I had the six ribs cut out of 1⁄4” x 1⁄4” balsa to length I trial fitted them and ended up cutting three filler pieces for the three left ribs. In the picture above, you can see the filler pieces laying in the openings between ribs. The lengths of the ribs from left to right in the featured image are 27/16”, 215⁄16”, 33/8”, 33/8”, 3”, and 21/2”. Chop that up to being human as in an ideal world they first and second set of 3 (left and right ribs of the stab) would be equal length.
Today I started finding the pieces that make up the rudder and fin of the aircraft, pinning them in place. I started with R1 (the top of the rudder) and R2, which I will say is a cross brace of the rudder making up the bottom of the front half that hangs over the top of the fin and connects back to the trailing edge of the rudder. I lightly sanded these two pieces and then pinned R1 into place making sure the left and right sides were equal distance from the edge of the workbench. The image at the bottom can be used for reference and how I left things pinned at the end of this session.
Using the fixed R1 piece and the angle of the R2 piece I lined up a piece of 1⁄4” x 1⁄4” balsa stringer and used the left hand sides of R1 & R2 to get the angle correct along with making sure the two middle slots lined up appropriately so the 1⁄2” x 1⁄4” balsa was verticle (used a triangle to help ensure right angles at the top). Having these pieces pinned in place I was able to cut the 1⁄2” x 1⁄4” balsa to length, 21⁄2” and the 1⁄4” x 1⁄4” balsa stringer that angles between the leading edge and R2 to lengh, 23⁄4”.
Yesterday I did some work on the elevators by myself. This involved getting the perimeter of the right elevator pinned in place and then measuring the length for the ‘cross-braces’ making up the internal structure of the elevators and getting them cut and pinned in place out of 1⁄4” x 1⁄4” balsa stringers.
The length of the stringers from small to large are 21⁄8”, 23⁄4” and 31⁄4”.
I was surprised by the looseness of the fit. It’s like they didn’t take into account some light sanding of the laser cut joints where glue would be applied.
Today Peter & John came over. John and I focused on figuring out how to piece together the tail, specifically the stabilizer and elevators. The ‘plans’ for this build leave a lot to be desired and I’m hoping anyone else trying to build this aircraft is able to use these posts to subliment the diagram based instructions provided.
The tail frame is being built based on a picture of the completed balsa frame with no measurements for reference but by figuring out the pieces by look alone! This session was about figuring that out and gathering all the pieces to make up the perimeter of the stabilizer (front portion) and the two elevators (back portion that wraps around to the left and right sides) seen in the featured image above.
Since no measurements, angles, etc. were provided I’m going to explain how we went about getting the pieces we have together. So far we have just been pinning pieces into place and the plan is to build the entire stabilizer and elevaters, pinned into place, before even thinking about gluing anything together. Once we gathered all the pieces we sanded anywhere there will be a glue joint.
Today Peter and I made more progress on the sides of the aircraft. The day started by removing all the clamps from the previous session and seeing how well everything stuck. Overall we were very impressed with how the wood working glue held everything together. Using this glue is new to us. We then trimmed as much of the excess we could, starting with my utility knife from front to back. Then to get a little closer switched to using an exacto knife to shave off some more in the curve for the wing (seen in the featured image)… once we get the other side done will sand to get the final finish.
Worth noting is that there were a few spots near the edges where the sheeting didn’t stick down so we used a good portion of medium CA in those spots, clamped it down and in one case sprayed accelerate on it. This didn’t take long to dry and then we were able to move right along.
Moving on to the other side we cleared all the excess away and flipped over the fuselage. We sanded any glue gobs and lined up the FU-SH-2 piece of balsa, which is 51 inches in length of 3⁄32” x 4″ balsa (as before) to see how it fit with the sheet flush to the back of the fuselage. At this point we basically repeated the exact same steps as before to get everything situated.
One thing we did do differently is apply the wood working glue a lot more liberally, as we thought we didn’t apply it thick enough last time. Also faster, as we were wondering if it dried a little to quickly on us.
Once the big piece was glued and clamped in place I cut a piece for the front, a little oversized, and we glued that piece in place and used a weight to keep it down. You can see how we left things in the two pictures below.
That wrapped up another building session as we were unable to progress. Next time will be cutting and sanding the two sides down to shape. Perhaps applying some touch up pieces as well.
Tomorrow morning I need to remove all the clamps and before the next session I need to give the work bench a good clean.
Today I sanded the sides of FU-ST-9, the balsa block at the very back, seen in the image below, to run smooth along the outer edges of the pieces it is glued between. I also glued some balsa pieces under FUH and to the back of former 10 (F10) to provide some additional support to the joint where FUH buts up against the former. Medium CA glue was used for this task.
I then moved on to prepping the side of the fuselage for the first balsa sheeting by making sure there were no glue gobs present and sanding down any bumps. We then lined up the FU-SH-2 piece of balsa, which is 51 inches in length of 3⁄32” x 4″ balsa to see how it’d fit with the sheet flush to the back of the fuselage. This sheet wasn’t quite long enough to reach to the front.
Wednesday I made more headway on the build, working together with Peter. First we removed the balsa block from tail that was temporarily glued in place to help support FUH. Then we moved on to this sessions main goals.
From a session by myself I had already prepped the FUBs to be glued in by sanding them and continued this session by ensuring the fit of FUDA (landing gear block) by trial fitting it with the FUBs in place and doing some directional sanding to get the outter edges to flow with the curve of the fuselage. During all this trial fitting we do have the firewall (F1) clamped in place, but not glued yet.
For the FUG pieces of 1⁄4” x 3⁄8” hardwood, to be the servo mount for the rudder, elevator and throttle, I placed it in and made a line with a pencil to mark the length and then sawed it off and repeated for the second piece. The measurements in the instructions are to make it 35⁄8”.
Once we were happy with how all the pieces (FUBs, FUGs & FUDA) were going to glue in place I mixed up a batch of glue. I started by: