Radio Control: Scale

Radio Control: Scale

Bob & Dolly Wischer

CHICAGO EXPO

The Tenth Annual Greater Chicago Radio Controlled Model Show, popularly called Chicago Expo, has moved to a new, larger site at the Odeum in Villa Park. The building has vastly greater space, with no crowding of exhibitors compared to earlier locations. There was space indoors for a large pool to accommodate boat operations and a track for model cars, with ample space for spectators around both areas. The building is sufficiently large to contain twice the previous number of commercial exhibitors. One-half of the structure is normally used for soccer games by the Chicago Sting team.

There was also a flying site of limited dimensions just outside the doors, suitable for helicopters or small planes. A fast delta-winged model was flown; its landing was made by catching it in a blanket. A large, raised, balcony-like area housed the swap shop—the only really crowded space in the building. Like most swap shops, it was 99% sales and 1% swap.

New products displayed were of particular interest to Scale modelers.

Ace RC

Ace RC exhibited its new Servo Pacer, a device that plugs in between receiver and servo to pace the servo at a slower rate for scalelike movements of sequential retracts, flaps, sliding canopy, or other functions that require slow action while maintaining full power. The Pacer allows full control of transit time (up to 8 sec.) in addition to adjustment of stopping position at both ends of servo travel. Kit price will be around $20.

• Benefits:
• Simulates hydraulic actuator action for flaps that otherwise zip unrealistically.
• Eases demonstration of smooth flap action for contest judges.
• Prevents loading the servo against mechanical stops, reducing battery drain.
• With electrically operated landing gear, a pair of Pacers can produce a realistic mismatch in retraction speeds. In some cases only one Pacer would be needed to slow one gear leg, but individual servos are required for each leg.

Ace also showed a new high-torque Ultra Servo with an output of about 50 inch-pounds. The servo features a coreless motor for very fast transit time, a tough gear train with near-zero backlash, an adjustable output arm splined to the shaft, and ball-bearing support. Kit price is expected around $50. The high torque could eliminate the need for a special servo just for landing gear retracts.

Jomar Products

Jomar Products exhibited items of special interest to Scale modelers:

• Sync System for twin-engine models:
• Featured in the October 1982 issue of MA.
• Available as a finished product; connector plugs and sockets must be purchased to match the user's equipment.
• Small magnets are fastened to the spinner back plate and a sensor is mounted directly behind the spinner. For spinners-less twins (e.g., many WWII bombers), modelers must find alternate, possibly hidden, mounting methods such as behind a dummy engine shaft extension.

• CAR (Couple Aileron and Rudder) module:
• Couples aileron and rudder electronically to achieve scalelike flight on airplanes that require combined control inputs (notably many Scale biplanes from World War I through the interwar era).
• With the module, the rudder is coupled to the aileron channel while the rudder stick is centered. The module decouples whenever the rudder stick is moved off center, permitting slips and point rolls that require crossed controls.
• No transmitter modifications or internal linkages in the plane are needed.
• Note: Many modern biplanes probably do not need CAR.

• Accessory controller:
• Can be used with electric brakes (Aeropiccola electric brakes from Italy are the known compatible type, though they are now off the market).
• When the rudder stick is moved off center, the brake on that side is energized for selective ground maneuvering; down-elevator energizes both brakes simultaneously.
• Can be used with any spare transmitter/receiver channel to operate two scale functions (lights, bomb or parachute drop, winch, ramp, etc.). Capacity: 1 amp.
• Jomar Products, 2028 Knightsbridge Dr., Cincinnati, OH 45224.

Aeropiccola electric brakes

A word about Aeropiccola electric brakes. We use them on our Emeraude and Beryl models, with a micro switch actuated by full down-elevator to energize both brakes simultaneously from three 500 mAh nickel-cadmium batteries. If brakes are applied at any speed above a fast taxi, tail-dragger models will nose over; the same will occur if higher voltage is used at any speed. They are useful to stop the model completely before takeoff to maximize contest points. We never use them after landing to shorten the roll. They are also used to be certain of stopping with main wheels in the "hangar" square in the Proto Taxi return maneuver in contests (now only an optional maneuver in Sport Scale class). Brakes of any kind are quite unnecessary when flying from a grass field.

Diamond-impregnated cutters for Dremel tools

Scale modelers who carve wood or plastic parts with the Dremel tool will find that cutters lose effectiveness by loading up with chips and can burn the wood (balsa or harder materials). We found a line of diamond-impregnated carbide cutters that eliminate this problem. They won't overheat or load up with wood fiber, plastic, or fiberglass.

• Available sizes: ball, disc, cone, and cylinder.
• Grits: coarse and fine.
• Shank: 1/8-in. diameter to fit the Dremel.

Petit Paint Co. — new military paint colors

Petit Paint Co., makers of Hobbypro products, has released new formulas for two Navy colors: Matte White and Light Gull Gray.

• Matte White:
• Federal Standard 37875, duplicates the flat undersurface paint of World War II Navy aircraft and completes the presentation of the early WWII Navy three-color camouflage scheme.
• Formula: To ½ pint (8 fl. oz.) of H-10 white, add 16 drops H-81 black, 6 drops H-49 Cub yellow, and 4 drops H-33 Stimson green, mixed with an equal quantity of Part B flat hardener. When mixed with gloss hardener, the same color represents the undersurface of present-day Navy and Marine Corps aircraft (e.g., A-4 Skyhawk, F-4 Phantom).

• Light Gull Gray (FS 36440):
• Used today in matte on the upper surfaces of the A-4, F-4, etc., along with gloss white on the undersurface.
• Formula: To 50 parts of H-10 white add 2 parts H-70 gray, 2 parts H-66 dark red, and 1 part H-96 Cub yellow.

Matte White and Sea Blue alone were used in the latter part of WWII. Toward the end of WWII and during the Korean conflict, Navy aircraft were painted gloss Sea Blue overall.

Corrugated ailerons

Many Waco models are being built, and readers have asked for methods to duplicate the corrugated-metal ailerons—the distinctive aileron stiffeners are essential to a true Waco look. We used several methods over the years:

• Vacu-formed styrene:
• We used the toy Mattel Vacu-Form machine to reproduce corrugations in .010-in. thick styrene sheet. The Mattel has a size limit (maximum part length about 2½ in.), so each aileron was pieced together in three sections of styrene over a balsa framework. Joints along the corrugations are visible but not conspicuous. The styrene sheets were epoxied to light, built-up balsa ailerons.
• Mold: made from ¼-in.-thick Plexiglass (or other acrylic). Parallel grooves were cut into the surface with a circular saw; the blade was tilted to 45 degrees and protruded about .040 in. The rip fence was moved for each cut in exact increments for even spacing of grooves. During vacuum forming, the styrene had to be quite hot for it to be pushed into the V-grooves. When the formed part was flipped over, the ridges were raised, closely simulating corrugations.
• For our 1-3/8-in. scale Waco, the ridge spacing was 9/32 in.
• A larger vacuum-forming machine (e.g., Formicator) can make full-length parts that don't require piecing, but it is wasteful of plastic unless multiple parts are molded from each sheet.

• Basswood strips:
• For those who don't object to tedious repetition, corrugations can be made from basswood cove molding strips. Model railroad shops that stock Northeastern Scale Models products have suitable basswood strips in several sizes that can be individually cemented to ailerons.

• Fiberglass and epoxy:
• Make a full-size mold (metal or plastic) with grooves as described above. Treat the mold with a parting agent (wax) and use masking tape to close off groove ends so epoxy will not leak.
• Pour a layer of epoxy, lay a single layer of six-ounce glass cloth, and add more epoxy as needed to saturate the glass. This produces realistic, strong corrugated sheets; internal aileron structure can be minimal. The finished aileron will look like metal without the effort of making a metal-forming punch and die.

There can be no substitute for real aluminum ailerons, however. A description of steps to form metal will be in a future column.

Bob and Dolly Wischer S-221 Lapham Peak Rd., Delafield, WI 53018

Correction

By mistake, we credited Bill Warner for taking the picture of Kelly Mathwick and Bill Lee-Richards' No. 3 which appeared on the cover last month. The credit should have gone to Phyllis Warner. From that cover picture and many others, we know Phyllis is a terrific photographer. We regret the error.

Transcribed from original scans by AI. Minor OCR errors may remain.