Radio Control: Giants
John A. de Vries
4610 Moffat Lane, Colorado Springs, CO 80915
IF YOU'RE A BEAN COUNTER, a number cruncher, or a frustrated accountant, you'll know what I'm talking about in this month's column. Have you ever calculated just how much it cost to put your latest Giant Scale creation into the air? If you have, I'll bet the number proved to be daunting, maybe even intimidating — to say the least.
What with kit prices running from three bills to well over a thou' (!) and engines in the $150 to $500 neighborhood, a Giant Scale model represents a rather healthy investment.
But that's just a start. If your bird includes a hefty set of retracts, they'll set you back another $200-plus, and the muscular servos Giants demand for positive control run from $80 to $100 bucks — each! Depending on the technique you choose to finish your bird, covering and paint can add another $50 to $60 to the soaring total.
And a bunch of other incidentals — pushrods or control wire, scale decals, hinges, control horns, glue, carbon fiber, wheels, sandpaper, masking tape, pins — all add up.
The preceding discussion is predicated on going strictly first-class. Several other courses of action cut the price of the Giant to more reasonable levels. Most require a trade-off of time and effort for some of the more expensive items that go into that bird.
For example: you can build your own Giant Scale engine following the techniques established by the pioneers in the big-bird field.
Engines on chain saws and leaf blowers are the appropriate sizes for our models. Purchased new, these devices can be disassembled to get at the power plant — prices well below those for ready-to-fly hummers. You may have to engineer an appropriate engine mount, and unless you're a skilled machinist, you'll have to have a propeller drive made to turn the gas burner into an aero engine. Even with this added expense, you'll still come out ahead of the game dollarwise.
You can save the most by building your Giant from scratch. Hundreds of different plans are accessible for such a project, and they're relatively inexpensive. Of course, you must cut out your own parts and purchase the necessary stick and sheet materials, but the price is going to be less than if someone else did it for you. The local hangar queen, the 10-foot Ryan B-5 with all the major construction completed, represents an investment of $125, well below what a comparable kit would cost.
The acres of covering that the model requires can be acquired at a dry goods store. A few yards of Dacron coat lining plus a can of Balsarite will run $15 to $20, and the bird will be ready for paint. The Dacron will tighten nicely with the application of hot air from the old heat gun, and of course, it'll be applied with a hot iron.
A few cans of Krylon paint from the hardware store will help keep the cost down and provide the necessary finish for a bird powered by a gas burner.
Many available Giant Scale designs require formed cowls and/or wheel pants that can be obtained from a variety of suppliers or from the designer himself. They're great if you're in a hurry to get your model into the air — and well worth the price.
If you have the time, however, you might consider forming them yourself, with the attendant savings. Again, you're trading time and effort for invested bucks.
There are other money-saving techniques you might consider.
- Giant Scale wing ribs take a bunch of material because of their size. Except for root ribs and ribs to which landing gears or struts are attached, ribs can be cut from 1/4-inch foam-core cardboard. Foam sheet is relatively inexpensive, and ribs made of it work just as well as those sliced from balsa.
- Although it may take a bit of design modification, making wing spars of aluminum tubing is another money-saving technique. The tubing is available in hardware stores as shower curtain railing. The price is right, and the tubing is strong. We had a fellow in our RC club a while back who designed and built over 60 models, and almost every one of them featured shower curtain spars. They worked beautifully.
- Of course, there's always the foam-wing alternative. Cut them yourself, and the price will be minimal. Provide the necessary templates and drawings to one of the professional wing-core cutters, and you'll still save a bundle.
Good friend and partner, Dick Phillips, the Giant Scale pioneer, has yet another money-saving technique that might interest you. Dick buys a knot-free spruce plank and strips his longerons and wing spars from it, using an ordinary power table saw. A thin plywood blade is installed, and the resulting sticks are a lot less expensive than the same ready-to-use material at the hobby shop.
There are places in your Giant Scale model where the more expensive materials can't be avoided. A half-inch, five-ply (or more) firewall to anchor the engine is pretty much a given. Sturdy music wire is usually needed to cope with the landing gear stresses a model will experience. Bellcranks and control horns designed for heavy-duty Giant Scale use are a mandatory expense.
Any part of the model that is under stress should be made of the best available material — for safety considerations. Otherwise, with a bit of thought and consideration, many techniques can be used to keep the cost of your bird within reason!
A couple of items of interest have appeared in my mailbox recently from friends at Horizon Hobby Distributors.
The first is a new and more powerful Webra 1.20 glow engine for Giants in the 10- to 18-pound weight range. The engine weighs a reasonable 26 ounces. Part of the new engine's muscle comes from a new carb. Yours truly hasn't any experience with the big Webras, but I do have a Webra racing .40 that is one fine power plant. With Webra's reputation for quality, I'm sure that the new 1.20 should be a fine motivator for smaller Giants.
The other item is JR's latest RC receiver. Would you believe nine PCM channels in a one-ounce package? Add to this a circuit that is designed to exclude 3IM and 2IM interference, and you're talking about electronics that really are pushing the state of the art. Those Giant Scalers who acquire a JR 649S receiver are going to have to be careful with it — it'll get lost in the cavernous interiors of their birds!
New friend Brian Allen of Sterling, Virginia, wrote a while back. Brian wanted to do a biggie of the Consolidated B-32 Dominator, which would be some kind of four-engine model.
Unfortunately, I couldn't help him with his documentation research. But Brian has a never-say-die attitude and came up with a source of info that is a veritable gold mine — the National Air and Space Museum. Not much is surprising about the source, but Brian came up with the proper way to tap it.
First — and most important — you have to know the airplane for which you need information. You must be most specific on that point; scattergun approaches must be avoided. With the subject well-defined, contact National Air and Space Museum, Archive Division, Room 3100, MRC 322, Washington, DC 20560.
In a few weeks, a printout of what they have on your bird will be sent, along with ordering instructions. Of course, it's going to cost you for the paper copies of drawings from the microfilm reels, but the information will be well worth the effort.
Our sincere thanks to Brian for the good info!
Still on the documentation kick — if you need to know more about the Northrop P-61 Black Widow, let me plug the latest book from VIP Publishers, Inc. (P.O. Box 16103, Colorado Springs, CO 80935). Dick Phillips and yours truly have published Dave McLaren's history of the big WWII night fighter.
The 128-page book tells the P-61 story, along with more than 70 photos and a three-view of the Widow. The book is $16.95 plus $2.50 postage and handling. We're working on another McLaren book at present. The subject: the North American F-82 Twin Mustang in its various configurations.
Hope you're enjoying the big-bird flying season!
Transcribed from original scans by AI. Minor OCR errors may remain.
