Radio Control: Giants
John A. de Vries, 4610 Moffat Ln., Colorado Springs, CO 80915
Precision and realism in giant-scale models
Scratch a giant-scale RC modeler and you'll find an individual who admires precision. After all, creating a true miniature aircraft requires a high degree of accuracy. Attention to detail is the name of the game. Matching colors and markings doesn't allow imprecise effort, and craftsmanship must be of unrivaled quality.
The dedication to precision extends to the mechanical functioning of a great giant-scale model. The model should work like the prototype to garner points for realism of flight.
Air-driven retract systems and the realism problem
Among the mechanical functions requiring a high degree of precision is the installation of retractable landing gear on birds that need them. A warbird model without a folding gear is almost unthinkable!
Although electrically driven retractable landing-gear systems are available, the majority of scale modelers rely on air systems to cycle their models' retracts. Compressed air is stored in a reservoir within the model, and a servo-operated valve meters it to pistons that actually move the gear. Most air-retract systems, despite functioning as advertised, leave something to be desired when it comes to realism. Generic systems fold the gear right now, both struts moving rapidly in unison. That isn't the way the gear comes up (or down) on real airplanes. Full-scale retracts move the struts at different rates and are relatively slow compared with their model counterparts.
Until now, the conscientious RC scale modeler has tried to achieve retract realism in a roundabout way. The usual technique involves stringing a wheel collar on the plastic air lines that connect the retract control valve and the strut piston. Compressing the air line with the wheel-collar set screw slows the retraction action to a more realistic rate by restricting airflow.
The system requires a lot of fiddling to get retraction rates right. Too-tight a collar might puncture the plastic air lines. If that happens, it defeats the entire process because a leak in the lines usually results in an inoperative system. A wheels-up landing can spoil your whole day!
Ultra Precision valves (Ultra Precision Limited, 1244 Honeysuckle Crescent, Oakville, Ontario, Canada L6H 2S8)
Ultra Precision Limited has an answer. Ultra Precision's retract air valves are true wonders that work with most available retract systems.
U.P.1 valve
- Incorporates a built-in speed control.
- Adjustable needle valves control the speed of retraction and extension of each landing-gear leg of an air-driven gear system.
- Locknuts on the needle valves hold the settings precisely once set.
- Retraction cycles can be controlled from 1/10 of a second to a full 20 seconds for maximum realism.
- The system works from maximum pressure to minimum.
Not content to rest on its laurels, Ultra Precision tackled the P-51 sequencing problem and came up with another winner.
When the pilot moved the gear handle on a P-51, a lot of things happened: first the landing-gear door covers popped open, then the struts retracted into the wing recesses, and finally the door covers closed over the retracted wheels. In model form, that's one complicated sequencing system. Ultra Precision's U.P.2 valve does it in true-to-prototype fashion.
U.P.2 valve
- Provides proper door/gear sequencing in a compact 2.3-oz. package.
- The speed of the operation is controllable.
- Door rates are individually adjustable, as is the speed of the landing-gear leg movement.
- The system requires only a single servo.
Phillip H. Soden of Ultra Precision indicates that a U.P.3 valve is under development for birds like the P-47 Thunderbolt. The Jug had landing-gear doors that were always open when the gear was extended but closed over the wheels when they were retracted. The U.P.3 will handle that class of retracts and close the doors when the gear is up. The U.P.3 should be available by the time you read this column.
Video: Aerodrome '92 and full-scale replicas (Dick Hansen, 10807 SE Stacy Court, Portland, OR 97266)
If you're a World War I aficionado, Dick Hansen has a videotape that'll be right down your alley. Dick attended Aerodrome '92 at Guntersville, Alabama, and filmed a host of flyable full-scale replicas of the aircraft of the Great War.
Like Dick's other tapes, #16 is in full color and can provide great documentation for your SE-5A, Fokker D-VIII, or other World War I fighter. Probably the greatest value of Dick's tape is that it gives you the feel of flight realism. After watching a full-scale triplane boring holes in the Alabama sky, you'll be eager to emulate the flying with, say, your 1/4-scale Fokker Dr.I! Dick's $19.95 tape also includes a short visit to the U.S. Navy's Air Museum in Pensacola, Florida.
ViP Directory of Giant Scale Plans — Volume 3 (ViP Publishers, Inc., P.O. Box 16103, Colorado Springs, CO 80935)
Volume 3 of ViP's Directory of Giant Scale Plans is now available. Dick Phillips and I run a small publishing company, ViP Publishers, Inc. As in the first two volumes, we've examined 50 more giant plans. We've included historical and documentation data for most of the models as well as our estimate of the difficulty (or ease) of construction for all of them.
- Price: $14.95 plus $2.50 shipping and handling (paperback).
- We're already working on Volume 4—making a total of 200 different sets of drawings that we've examined.
Dry Line Temporary Adhesive for cutting templates
If your thing is scratch-building from plans, we've found some stickum that is ideal for holding parts templates in place while you cut them out.
You've probably used Post-it notes, those neat little squares of paper with the glue on their backs that are easy to attach and remove. The same sort of stickum used on Post-its is available at office supply stores under the trade name Dry Line Temporary Adhesive, made by the Liquid Paper Company. The adhesive can be purchased with a refillable dispenser or as refills.
- The dispenser lays down a 3/8-in. stripe of adhesive.
- The adhesive is not a liquid; it comes adhered to a tape and separates from the tape when applied.
- No drying time is required.
- It is easy to apply templates and doesn't leave any appreciable residue on balsa or plywood parts.
- Templates can be pulled up and repositioned to get the most out of the material, as long as the surface is dust-free.
Make sure you get the Temporary Adhesive, because the Dry Line people also make a permanent version of the glue tapes.
Hope those of you who live where the snow flies are well into your winter's giant-scale project. And to the readers who live where the sun always shines, have fun at the flying field with your big birds!
Transcribed from original scans by AI. Minor OCR errors may remain.
