Goto Part 2 (Main wing, Tail Feathers, Engine mounting)

Goto Part 3 (The rest of the story)

We had built a UltraStick Model from Hangar 9 and the that plane used a Saito 182 Twin. This kit is a scaled down 40 version with the same flight surfaces and supposedly flight characteristics as its big brother. We will use a Morris Hobbies 0.53 (Rossi built) with its tuned pipe for the 40 version. The flap/aileron version will be build from this kit. We might even have a photo session with both planes together at the flying field. This is an ARF kit with about 90% of the work already done. The covering is UltraCote in Blue/Yellow/White and Black lettering, More information about the plane can be found at Horizon Hobby

The 40 size has the following specs:
  • Wingspan: 57 3/4 inches
  • Area: 700 SqIn (ailerons only) 715 SqIn (Flap and Ailerons)
  • Fuselage Length: 51-inches
  • Weight: 5 - 6 pounds
  • Wing Loading: 16 - 19 ounces/sq ft
  • Engine: 0.40 - 0.58 Two stroke 0.50 - 0.72 Four Stroke

Kit_Contents The kit was well packaged and was in good shape when it was purchased from one of the local hobby shops. (Support your local hobby shops!)
Kit_Contents_out Out of the box, you can see that everything is individually wrapped for protection. The kit included everything to build a traditional four channel model or one with flaps and ailerons. We will build the flap/aileron model to have the increased flying capabilities. Some of the included hardware will be replaced and alternatives used due to builder preference. We will start the building process by weighing everything and making some preliminary building changes. We fly off a grass runway and 3-inch wheels (minimum) make life easier. The included tail wheel assembly will cause damage to the rudder if a hard landing occurs, so a Klett unit will be used instead, even if it turns out to be heavier.
MainWing_Hinges The instructions had us start by installing the main wing contol surfaces. We set aside the single strip ailerons (we'll use them on another project!). The control surfaces are built light with separate trusses and ribs, not a solid piece of balsa! This kind of high quality is unusual in the 40 size ARF. The ailerons and flaps are attached using the supplied CA hinges. These were easy to install. Even though the instructions didn't request it, we did crease the hinges at the center and folded them back and forth several times before inserting the pin and centering the hinges between the main wing and the control surfaces. Make sure you only do this a few times. You do not want the hinge to delaminate (come apart). The surfaces moved up and down easily when the hinges were glued using thin CA. We tugged on each of the control surfaces to make sure they were secure.
Ultracote_Gap_Seal Even though the instructions mentioned using white Ultracoat to seal the hinge gaps, we didn't have any on hand. We did have some nice purple Oracover handy and used it instead. This is a low temperature covering and it is light and very tough. We applied four 1-inch by approx. 12-inch long strips using our covering iron. While the iron was out, we turned the heat up and ironed the wrinkles out of the Ultracote covering. We used higher heat (~290 degrees) than used to apply the Oracover and let heat and patience remove the wrinkles. Using pressure on the covering will only iron in the wrinkles.
Epoxy_MainSpar The main spar was marked in the center and then slipped into each wing half BEFORE the epoxy was even mixed (test fit). The spar went into one wing about 1/16-inch past the center and was exactly at the center in the other half. In some ARF kits, we found the spar was too long and we had to shorten the spar by cutting it. This one was OK to use as received. The Hangar9 30 minute epoxy was nuked in our shop microwave for 15 seconds (make sure to take the caps off!), measured, mixed for a minute or so and a thin coating was applied to both spar sockets and the root ribs, making sure to coat every bit of the wood surface. Then a light coating of epoxy was spread on the spar before it was slipped into one wing half. The remaining wing half was slipped onto the spar and slid down to the other wing half. All excess epoxy was wiped away using a paper towel with alcohol on it. Don't use too much alcohol or some of the color will come off the wing covering.
Epoxy_MainWings Just as advised in the instructions, we carefully rechecked the wing alignment and made sure each wing was flat on the table (notice the weights used to hold the wings). We used wax paper on the building table to make sure we didn't glue the wing to the table. Masking tape was used to seal the glue line and the wing was allowed to set overnight. (You probably already know that Epoxy sets, not dries in the traditional sense of the word).
Ultracote_Gap_Seal2.jpg The purple gap seals are really noticeable. This should help in being able to see the plane as it flies overhead. The purple adds a nice touch, we think! The completed wing weighs 568 grams at this point (1.25 lbs or 20 ounces).
Engine_Mount Since the main wing was glued and won't be ready for the next step until tomorrow, we started on the fuselage section. The supplied engine mount has been known to fail, so we decided to use a Great Planes 60-90 engine mount. The GP 60-90 mount was cut down for our use. The weight of the supplied mount and the modified GP 60-90 was about the same at 100 grams. We also used our sanding bar to sand the firewall and the back of the engine mount. Neither of them was flat. You can see by the non-white areas on the firewall (in the photo). We also drilled new holes for the mount, removed the old t-nuts (blind nuts are the same thing...), cut and epoxy glued a 1/4 inch aviation plywood piece behind the existing firewall and added new blind nuts. The Morris 0.53 engine and tuned pipe will look great on this model. The engine and pipe weigh in at 665 grams (about 1.46 lbs or 23.4 ounces).
Goto Page 2 (Main wing, Tail Feathers, Engine mounting)

Goto Page 3 (The rest of the story)

Last Updated: 9/17/01