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.70 - .91 4 - stroke (11.5 - 14.9 cc 4 - stroke) |
The Midwest Little Cap 232 fits neatly between smaller .46 powered aerobatic models and the larger 1/4 scale planes. Having flown primarily .46 and .60 sized aircraft, the Little Cap was just different enough to fill the need for a more powerful, performance oriented plane. A kit inventory showed all parts present with no damage. An older review of this kit in R/C Modeler magazine indicated that all parts were laser cut. This was not the case with this kit, as all parts were die-cut. The cutting of the plywood parts was of good quality but all balsa parts were a prime example of "die-crushing", particularly the wing ribs. The parts separated well, but the dies need to sharpened to cut down on the sanding required. Rolled plans were included as was a good hardware assortment. Construction began with the tailfeathers. The horizontal stabilizer was constructed entirely of balsa sticks. It took time to cut the brace angles properly. After all the pieces were joined with thick CA, the stab was block sanded and set aside. The elevator was next and it too was of balsa stick construction. The centers were laminated balsa with plywood inserts for control horns. These were glued together and put under flat plywood with a jug of water on top. Pica Glu-It was used throughout the construction. If a square sanding jig had not been used, the stick construction would have taken even longer. Brass inserts were used for the control horns, which were long 4-40 socket head bolts. Finally, the leading edges were rounded and the assemblies were block sanded. The same stick cutting and fitting was required in building the rudder. Control surfaces were slotted prior to beveling edges since a square edge is much easier to mark and cut. One (1) slot was cut by hand since the Great Planes Slot Machine would not fit between the rudder top and top hinge slot. The rudder is huge! The fin was built last. This time, the top slot was cut before the sticks were glued together. Pica Glu-It was used to help fill the small gaps around the stick junctions. After the leading edge was rounded and the components were block sanded, the tailfeathers were complete. The fuselage sides butt together with no interlocking tabs. Doublers provide reinforcement, but the sides have to bend right at the joint when they are assembled and glued to the fuselage top. The fuselage top was also glued using butt joints with the formers and fuselage sides providing support. One gap was filled with a glue/balsa dust mix to get a straight joint. The fuselage was built upside down and pinned on the plans. Lots of tape and clamps were required to hold things together for gluing. The wide radio compartment was evident already. After the fuselage rear section was completed, the balsa longerons were added and the stabilizer platform was glued in place. The firewall was drilled for a Dubro vibration reducing mount and #10-32 blind nuts were installed and secured with epoxy. The landing gear block was drilled for the supplied dowel pins before it was epoxied in place. This deviates from the instructions somewhat but this chore is more easily done before the block is in place. The landing gear is well designed and will take hard landings. A metal spatula from Squadron was used for epoxy application. This allowed small amounts of epoxy to be troweled in place and easy cleanup with denatured alcohol. The turtledeck formers came next but this it would have been better to wait until the wing was mounted to avoid a lot of hanger rash on this section during construction. The bottom of the canopy rear former was more sturdy if beveled to fit against the cockpit floor. The forward and rear sheeting were completed with no real difficulties. It was trimmed first and then sanded to fit flush with the top of the formers. The rear turtledeck cap was then glued in place and shaped, followed by the fairing blocks. Most of the initial shaping of these pieces should be done they are glued in place. If they are glued in place before shaping as recommended in the instructions, this task can be very difficult. The pinned firewall was installed and the fuselage was complete. The wings were built next. The ribs have tabs for alignment and the wing was built upside down. The main spar was a little twisted and was replaced with a straighter piece as the inside ribs did not lie flat if the original spar was used. Straightforward sheeted construction was used with capstrips on the exposed ribs. After installation of the top sheeting, the control horn block was glued in. Bond paper was rolled into an aileron servo wire tube and glued in position. The bottom portion of both wing panels were then sheeted. The sheeting installation was made easier by dampening the balsa. Top capstrips and wing tips came next, then shaping of the leading edge. A balsa plane was used initially, followed by a Great Planes compound sander. Ailerons were cut out of the wing using a fine tooth jabsaw. The dihedral brace opening was knocked out on both panels and the thick ply brace was sanded to fit. The wing was joined with epoxy after checking wing tip incidence with a Robart incidence meter. Fiberlass tape was epoxied to the wing center joint and a heat gun was used to help flow the epoxy. Epoxy must be used sparingly as it will flow and fill the cloth very well, but the heat makes it set up fast. After filling and sanding the wing center reinforcement tape, the wing tongue was sanded slightly to allow the wing to sit properly in the saddle. The Little Cap uses a very strong integral tongue rather than wing dowels. The plank which the wing bolts thread into seemed thin so an additional plywood plank was added to it before drilling and tapping for the wing holddown bolts. Fiberglass tape was applied to the inside of the cowl with PVC cement. This technique of applying fiberglass cloth seemed to result in a strong cowl as the PVC softens the plastic slightly and the cloth bonds very well. Cooling holes and prop hole were cut next. This was difficult at best and a cutoff wheel and sanding drum were used in a Dremel tool to help with the task. The cowl was test fitted and mounting holes drilled. The wheel pants were drilled and fitted with wood reinforcing disks. The seam of the wheel pants was lined with glass cloth and filled on the outside with Bondo spot putty. All covering pieces were laid out in AutoCAD and then cut from rolls of Ultracote. The stabilizer and elevators were covered first followed by the rudder and fin. Balsa filler was used to fill the gap between the rear turtledeck and fuselage. Fuselage bottom and sides were next, then front and rear turtledeck. A 1/4 scale pilot was fitted as suggested in the instructions but this looked too big and was replaced with a 1/5 scale pilot. Before the wing was covered, the plane was assembled with the major components and lateral balance checked. The Little Cap needed 3/4 oz. in the left wing, which is not surprising since the engine is mounted with cylinder head to the right. After the wing was covered and the graphics from Rockin' Rose Graphics were applied, it was time to install hinges. Great Planes medium nylon hinges were installed with Elmer's carpenter glue. This resulted in a very strong installation and this glue does not stick to the hingepin like epoxy does. The tailwheel was built using two (2) nuts soldered on each side of the wheel rather than wheel collars. The elevator pushrod was a dowel and it was a little tough to get holes required for the control rods drilled at exactly 90°. Thread and CA were used to secure the rods. All other linkage installations went routinely although the throttle linkage required a shaped piece of wire to avoid a severe bend in the throttle cable. The backplate was removed from the OS .91FX and the engine flushed with fuel. It was then reassembled and mounted on an American Hobby Products test stand and four (4) tanks of fuel were run through it at a very rich setting. A Sullivan 11 oz. tank was assembled and installed in a foam bed in the rather cavernous tank area of the plane. The engine and Bisson Pitts style muffler were then installed. The original canopy was scratched and Midwest sent another at no cost. This canopy was cleaned with plastic cleaner installed. The cowl was painted with Cheveron Perfect Paint to match Ultracote True Red but the results were not good but this may be due to painting technique. The wheelpants look better because there is a little distance from the Ultracote. The receiver and servos were installed with no problems. A Futaba R127DF receiver and 9202 servos were used. Control throws were set at the recommended high and low settings. The elevator linkage was repeatedly adjust in an effort to eliminate buzzing from the servo. It finally stopped when the control rods were bent so they did not rub on the exit hole at any point during their stroke. Initial balance showed that 1 oz. of lead was needed under the stabilizer to balance at the recommended point. A tank of fuel was run through the engine on the ground to check mixture. Response was excellent, even at a rich settings. All fasteners and fittings were double-checked and a range check was performed with one section of antenna extended and it checked good at 150 feet. The first flight was done in a 7 mph crosswind. The astounding rudder response handled this easily and the plane lifted off in about 100 feet at half throttle. About three clicks right aileron trim were needed for level flight. It was apparent that the throws were excessive even on low rates as the Little Cap snapped at anything over 1/3 up elevator. The initial flight was performed with caution while flying around the pattern just to burn some fuel. Landings were solid with no tendency to tip stall as long as some power was maintained through touchdown. Subsequent flights with the low rates set lower by about 2° less than recommended resulted in solid but responsive flight. Trim flights revealed the Little Cap needs additional right and up thrust. A local IMAC pilot said that his large CAP also needed up thrust. The wing location of the CAP design makes the up thrust necessary. Knife edge flight shows fairly strong roll and pitch coupling. Any maneuver requiring rudder is dispatched with ease. Hammerheads are tremendous fun with this much rudder authority. One of the aileron horns broke on the third day of flying. These horns are just 4-40 bolts and not very substantial. These were replaced with Sullivan steel horns. On the fifth day of flying, one of the elevator horns broke. This is definitely a design flaw. The elevator bolts were replace with stainless bolts of the same size. All stock plastic pieces cracked within the first fifteen (15) flights. Both cowl and wheelpants have been replaced with Fiberglass Specialties replacement items as shown in the photo. The cowl is much longer than the stock cowl, resulting in much more material around the mounting holes while still maintaining proper spinner clearance. This plane is not intended for a beginner and requires attention at all times but an experienced pilot will appreciate its responsiveness. Some of the hardware is sub-standard and the plastic is little more than throw-away. Additional money spent on aftermarket hardware and fiberglass parts resulted in a plane that is reliable and great fun to fly. |
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