Sailplane Aviation Concepts 1/3-scale Schweizer SGS-233A
- Thread starter JimD
- Start date
JimD
50cc
Time to add stringers so we started with the aft fuselage section.
The holes in the stab mount need to be drilled on down through the hardwood blocks we added. To assist with getting these to be perpendicular, we used our drill press to drill holes in a piece of oak for use as a drill guide. This was clamped to the stab mount and the holes were punched on through. The fin was test fitted and looks to be perfect.
Next is the addition of the diagonal fuselage braces starting at the tail section. The next bay needs to have the elevator servo rails installed and then the diagonal braces. Since the servo is positioned off center, the brace on the left side needs to be keep out of the way to make room.
The stab was temporarily mounted to check alignment, looks good! Then the diagonals for the remainder of the bays were added.
WE are using the optional scale tail wheel and Gunny offers a detailed plan for installation. His addendum is available at Aviation Concepts and uses one of the Ohio Superstar assemblies. Hardwood blocks were added to the bottom of the last bay for mounting this wheel assembly.
The fuselage was removed from the building board and turned over so the internal access hatch supports could be installed and so that the wood screw that supports the tail post joint could be installed.
The holes in the stab mount need to be drilled on down through the hardwood blocks we added. To assist with getting these to be perpendicular, we used our drill press to drill holes in a piece of oak for use as a drill guide. This was clamped to the stab mount and the holes were punched on through. The fin was test fitted and looks to be perfect.
Next is the addition of the diagonal fuselage braces starting at the tail section. The next bay needs to have the elevator servo rails installed and then the diagonal braces. Since the servo is positioned off center, the brace on the left side needs to be keep out of the way to make room.
The stab was temporarily mounted to check alignment, looks good! Then the diagonals for the remainder of the bays were added.
WE are using the optional scale tail wheel and Gunny offers a detailed plan for installation. His addendum is available at Aviation Concepts and uses one of the Ohio Superstar assemblies. Hardwood blocks were added to the bottom of the last bay for mounting this wheel assembly.
The fuselage was removed from the building board and turned over so the internal access hatch supports could be installed and so that the wood screw that supports the tail post joint could be installed.
JimD
50cc
As to your question, "Will it tow?"
We have had two tow planes about this size and weight and powered with 50-55cc engines. We were able to tow sailplanes in the 3-4 meter span and 10-15 pound range pretty well. Larger and heavier sailplanes become more difficult to tow, not impossible, but more difficult.
When it comes to scale sailplanes, bigger definitely flys better! As for tow planes, same thing is true, bigger planes with bigger engines tow better. While it may sound counterintuitive, more horse power can make up for poor technique and/or lack of experience with aero towing. Being able to romp on the throttle and head for the sky, in spite of what the sailplane behind you is doing, has its advantages!
JimD
50cc
After spending a couple of days studying the pictures I took of the 2-33 that belongs to the Cumberland Soaring Group, it finally hit me that the interior is going to consist of six side panels and two seats. Here is the full-scale interior looking in through the rear door.
Getting the seats scaled to the size of the interior was the first order of business. We concluded that the interior scale cannot be exact 33% because the thickness of the model sides intrudes on the interior making the available room smaller than the full-scale. After some trial and error, we found that 28% gave us the best fit.
Next step is the side panels. The fuselage side panels in the full-scale are basically divided into three sections on each side. The first step here was to make three templates that fit into the sides of each of the three bays in the model.
Next step was to cut side panels out of hard 1/16" balsa sheet. Each unique panel will have details built onto it to create the interior. We started with the left rear panel and cut an opening matching the spoiler handle recess of the full-scale. Balsa stick material was added on each side and then more 1/16" balsa sheeting to finish out the build. The corners were sanded round and we got a test fit. Next panel is the middle left side...not finished, but stay tuned!
Getting the seats scaled to the size of the interior was the first order of business. We concluded that the interior scale cannot be exact 33% because the thickness of the model sides intrudes on the interior making the available room smaller than the full-scale. After some trial and error, we found that 28% gave us the best fit.
Next step is the side panels. The fuselage side panels in the full-scale are basically divided into three sections on each side. The first step here was to make three templates that fit into the sides of each of the three bays in the model.
Next step was to cut side panels out of hard 1/16" balsa sheet. Each unique panel will have details built onto it to create the interior. We started with the left rear panel and cut an opening matching the spoiler handle recess of the full-scale. Balsa stick material was added on each side and then more 1/16" balsa sheeting to finish out the build. The corners were sanded round and we got a test fit. Next panel is the middle left side...not finished, but stay tuned!
JimD
50cc
Bart, this is my build. Kit #003. Kit #002 was maidened at the Cumberland Summer Soaring event last week. The flying season interrupted my progress but I will be back on it this fall.
As for the build, it is very straight forward on fuselage and tail surfaces. The wings on the 1/4-scale model are a bit of a challenge, but Gunny designed a build jig (which is included in the kit) for the 1/3-scale wings to make the sheeting process much easier.
As for the build, it is very straight forward on fuselage and tail surfaces. The wings on the 1/4-scale model are a bit of a challenge, but Gunny designed a build jig (which is included in the kit) for the 1/3-scale wings to make the sheeting process much easier.
