CONTROL LINE AEROBATICS
Curt Contrata 6783 Nightwind Cir., Orlando FL 32818 E-mail: [email protected]
Several columns have been written regarding general construction techniques and basically old-school methods. The methods I have written about are the foundation for producing an honest-flying airplane, if not the perpetuation of our event.
However, anyone who has ever tried to produce an accurate rib set from a set of plans knows it can take an entire rainy Saturday. I must admit that it is not my favorite thing to do when it comes to modeling.
Many different methods of producing rib sets have been devised throughout the years, including some that require special, and often interesting, construction techniques to go with them. I don't feel that any one method is ultimately easier than the rest, but the variety of techniques certainly keeps what we do from getting boring. If you have made a few frustrated attempts at carving up a set of perfect ribs, only to find that you wasted not only a weekend but all of your best wood, there is still hope.
Laser cutting
It is time that I wrote about possibly the greatest advancement for every facet of model making in a long time: laser cutting. This has become a common method with which manufacturers produce quality kits of all types. Rarely, if ever, is there a win-win situation for manufacturers and consumers, but this is definitely one to put on the list.
Laser cutting is better for the manufacturer because it does not require any special tooling to produce a new product or when modifications are required to correct an existing one. For the consumer, the result is a product of much higher quality than with the old die-cut method.
Not only that, but since no special tooling is required, extremely short runs of specialty kits can be produced at reasonable prices.
Wait — it gets even better. The same tool that is used to cut our kits can be used to do a variety of other things, so more laser cutters are showing up across the country, and many of them offer affordable cutting services directly to modelers.
This is where things start to get exciting. Now it is possible for a club, or even an individual modeler, to produce a small number of rib sets, or even only one custom set, made exactly to specification.
Since the ribs are cut exactly the way you want them, you can have them cut with features that might help you during construction. These do not have to be new ideas; they can simply be refined versions of what various kit manufacturers have attempted in years past with limited success because of poor dies and bad wood.
Berkeley once produced a kit for a model called the Interceptor 35. It was a horrible kit, but it had some clever features. The vertical spar was notched in such a way that the ribs would snap into position when they slid onto it. However, it did not work very well in practice because of the quality for which that company was infamous. Still, it is a great example of how we can design into our parts some mechanical advantage to aid us during construction.
The Carl Goldberg kits often had detachable feet on the ribs to help keep the wing straight when building on a flat surface. A variation of this was the way Midwest Products produced the Dave Hemstrought PT-19 kit. On it, there was a detachable portion on the underside of the ribs, forming a flat spot on their bottoms. Once the wing was taken from the board and ready for sheeting and capstrips, the portions of the ribs were glued back in place to form the complete ribs.
I like to add feet to my ribs, similar to the Carl Goldberg method. The wings I am building now have molded-sheet leading edges. The way the ribs are cut, the foot starts just aft of the spar so I can mount the molded leading edge while still on the board. Where the bottom trailing edge goes, I make a 1/16-inch slot so the top and bottom pieces can be glued in place while still on the board. Small tabs hold the feet in place until the bottom capstrips are applied.
If you build on rods, there is no better way to get all of the holes in perfect alignment than with laser cutting. There is no limit to what you can have cut, with whatever features might be advantageous for you to construct a better model. While you are at it, what you have cut does not have to be limited to parts. Lasers can cut fixture blocks just as accurately, or perhaps an entire fixture system, with plywood cut as easily as balsa.
With laser cutting, you are charged for laser time; the more time it takes to cut the parts, the more you are charged. With that in mind, the price for two sets of normal ribs I had done was $25, and the cutter supplied the wood. The next few sets I had done were quite a bit fancier, with provisions for my fixture system. Those rib sets were approximately $23 per set, and I supplied the wood.
Since laser time could add up for an entire model, I limit its use to rib sets, with all larger parts and the squared ones such as fuselage formers cut by hand. The company I have used with great results is Laser Arts Custom Laser Cutting, but many others offer this service at competitive prices.
All companies take computer-aided design (CAD) files, and some will take other file formats. All of them seem to offer some form of drafting services, but usually at an additional cost. The Internet is the best place to search for a company to do your cutting; then you can e-mail the file.
If you are interested in the laser-cutting option for your next set of ribs but do not have access to the Internet or a CAD program, ask around in your group of flying buddies. This technology is becoming so commonplace that someone in your circle of friends is bound to be able to help you out.
Almost Ready to Fly (ARF) and new kits
Something that began as what many thought to be an April Fools' joke on the Internet has become a reality: Almost Ready to Flys (ARFs) for control line. This is not a new concept overall, but the exciting thing is the specific models chosen for introduction and their prices.
The Flite Streak and the TopFlite greenbox Nobler are now available through Great Planes Model Distributors as ARFs for prices that compete with their unbuilt kit equivalents at $69 and $109 respectively.
Many suspected that one day we would see something besides Fédération Aéronautique Internationale Combat models available in ARF form, but it seems like these two have come along rather unexpectedly and at incredible prices.
It will be interesting to see how well they are accepted and if events will be designed around them. I think it would be fun to race the Flite Streaks in the morning then fly Combat with them in the afternoon, and I can imagine an all-ARF-Nobler stunt event.
There is even a new stunting 1/2A in the works from Estes called the Hyper Viper, available through Tower Hobbies. It is lighter than the former Me 109 and has a stiffer wing. The fuselage nose is stronger than that of models in the past; the engine is bolted to the firewall, resulting in a stiffer nose with less vibration and better engine runs.
Mike Pratt claims that in the hands of a good pilot, the Hyper Viper can do the pattern on 35-foot Dacron lines. Admittedly, this is with some difficulty on the Hourglass and a rule-book-size Four Leaf Clover; however, you can get more performance by boosting the nitro, adding Tee Dee components, and using 42-foot .008 lines.
The Hyper Viper has a 27-inch wingspan, weighs 9 1/2 ounces, and has adjustable controls, tip weight, and a leadout guide. Mike says the Hyper Viper is a blast to fly, and it is priced at just $49.99.
Bi-Slob
If you have never flown a Bi-Slob, now is your chance. Brodak Manufacturing is producing it, and I cannot believe it has taken so long for someone to produce this kit. I had always wanted to build one, and I did when the plans became available a few years ago. It was designed to be simple to construct, and it can be assembled in record time.
Keep the Bi-Slob light, fly it as slow as you can, and overcontrol it like crazy. It will take a while to get the hang of it and gain confidence in the model and its unique flying ability, so give it a chance. It breaks every rule you know about flying, and it could be the most fun you will ever have with a control line model. I am a firm believer that everyone should have a Bi-Slob one day.
Keep the e-mails, letters, and pictures coming. They are always appreciated.
Sources
- Laser Arts Custom Laser Cutting
http://members.aol.com/laserartco/
- Brodak Manufacturing
100 Park Ave. Carmichaels PA 15320 (724) 966-2726 [email protected] www.brodak.com
- ARF Flite Streak and Nobler: Great Planes Model Distributors
Box 9021 Champaign IL 61826 www.top-flite.com/index.html
- Cox Hyper Viper: Tower Hobbies
Box 9078 Champaign IL 61826-9078 (800) 637-6050 www.towerhobbies.com/
Transcribed from original scans by AI. Minor OCR errors may remain.
