Free Flight Sport
Gene Smith [[email protected]]
1/2A Viking One Design
It's time to order your kit from BMJR Model Products or plans from the National Free Flight Society (NFFS) Plans Service for the 1/2A One Design model for 2011: the Goldberg Viking. See the "Sources" list for contact information.
You can build the original-size aircraft with the NFFS plans or the approved smaller version that BMJR kitted, but either model must use a Nostalgia-legal .049, a Tee Dee .049, or a .051 engine.
My Viking is the smaller version, and it flies well in a right/right pattern. I have heard of others flying left/right or left/left, so make your choice.
The NFFS Nostalgia Gas Committee has voted to allow the Galbreath/Nelson head to be legal for the Cox Killer Bee. Prior to this, the only legal head was the Cox 325.
Tom Hallman — DT hinges and stabilizer setup
Tom Hallman has developed some extremely nice DT setups for his scale models. It seems like every design needs its own "tweak"; the hinges on Tom's Fokker D.VII were fabricated by using a UHU glue stick to adhere, cross-grained, two small sheets of Japanese tissue.
A particular problem was deciding the sequence for installing the hinges on the front of the stabilizer. After serious pondering, Tom installed the two lower hinges inside the fuselage, leaving loose the ends that would attach to the bottom of the stabilizer. He then placed the stabilizer in the down position and attached the top hinge with UHU. After the glue was dry, Tom lifted the stabilizer to just beyond the maximum DT angle and attached the loose ends of the lower hinges. When that dried, he lowered the stabilizer to be flush with the fuselage and was finished.
Tom discovered that the UHU wasn't strong enough to hold the top hinge in place. He solved that by "welding" it with a small amount of CA. Never apply CA directly from the bottle; you'll deliver too much. Put a small drop on waxed paper or Mylar, dip the head of a pin in the CA, and then apply it to the surface.
The stabilizer was raised by a length of .010-inch-diameter wire embedded in a 1/8" stick located vertically beneath the stabilizer. The stick was attached to a 1/2"-wide piece of 1/16" sheet plank, which was already built into the frame.
Dohrm Crawford — Cessna Bird Dog (Scale)
Dohrm Crawford has been very active in free flight with the Atlanta group. His interest has been primarily endurance models, but he decided to try scale with a 30-inch-wingspan Cessna Bird Dog that he built from a Herr kit. Dohrm said it is a nice kit, but he was concerned that there was not enough decalage. He modified the stabilizer mount to put slight negative incidence in the stabilizer and equipped the model with a pop-up stabilizer in case a thermal gets too possessive.
The Bird Dog has a special meaning for Dohrm, because he flew one in combat as a forward air controller. The Herr kit is available from Penn Valley Hobby Center.
Paul Bradley — Small-field Comet P-51A
Paul Bradley, the "Small-Field Flying" columnist for MA, is an excellent model builder. As do many of us, he enjoys the old Comet plans. He sent a picture of his P-51A.
It spans 18 inches and weighs 22.5 grams (less rubber); the three-blade propeller and nose plug contribute approximately 5.7 grams to that total. The rather heavy front end compensates for the weight of the rubber motor, so the CG is close without added weight.
Paul found that a single loop of 3/16-inch rubber is perfect for power. The tissue is white domestic. Color and markings were applied with an ink-jet printer. Some weight could have been saved by using a better grade of tissue, but the model flies well anyway. The tissue was sealed with two coats of 50/50 clear nitrate dope.
Paul has converted the Comet plans to CAD: the P-51, P-40, and Stinson SR-7. Both the plans and color tissue patterns for all three are available free on his Web site. He also offers many No-Cal plans and plans for the old Jigitme series of models, complete with printable color patterns.
Nason propeller clutch (Art Holtzman)
I mentioned the Nason propeller clutch in the November 2009 column; Tom Arnold used it in his Ki-100. Several modelers sent questions regarding the clutch, so I obtained additional information from Art Holtzman, an ardent fan of the device. Art said George Nason designed the clutch for use on plastic propellers, so he could eliminate the plastic ramp. Now many are using the mechanism on wood propellers too.
The primary advantage of the clutch is that engagement is automatic at any attitude. Thus no blood and Band-Aids are encountered at the flying field (only at the workbench). If the power hiccups, most other clutches will disengage and not recover. The Nason will re-engage by itself in a half revolution of the drive dog.
Art experimented with a square bearing tube let into the hub surface. His original intent was to allow the claws to be shaped off the propeller so the propeller itself wouldn't be damaged during the bending process.
The propeller is normally drilled and the cross tube adhered in place with CA. Then the claw wire is inserted with the first claw already formed, leaving the second to be formed in situ.
On Art's first propellers, when he thought the claw needed to be beefy, that variant made sense. He has since discovered that the claw wire need not be large, so he has reverted to the round bearing tube.
The prop shaft on his Aristocrat Bostonian is .032" and the claw is .025". The claw could easily have been .020", and it would still have worked fine. The advantage of the lighter wire is that it can be formed after the bearing is installed in the propeller.
Now Art inserts a round tube and makes small (with the grain) slits on each side of the tube using a #11 blade. The slices create paths for the CA to penetrate better. He estimates that the claw wire can be close to two-thirds of the shaft diameter and will satisfactorily take the load of the rubber motor.
Enlarge the components when using the Nason for a larger model. Art modified one of his old Senator propellers for the Nason. The shaft is .055" and the claw is .048", riding in a .063"-ID tube. The sloppier the fit, the better it works. CA around the cross tube makes the whole installation as strong as nails. Art had no problem bending the second claw.
FF Cookup group — Flying Scale Models of WWII
Many aeromodelers enjoy finding unique airplanes to model. The next best thing is finding a unique finish for a well-known design. This past winter the FF Cookup group elected to build aircraft from the Model Builder plans book Flying Scale Models of WWII.
Eric Monda constructed both the Hurricane and the Zero from the book’s plans. In a switch from fighter livery, he finished his Hawker Hurricane in the post-WWII air-racer version. Its paint scheme was inspired by the racer "Last of the Many," flown by Group Captain Peter Townsend and sponsored by Princess Margaret. The scheme replicates the Hurricane flown in the 1950 King’s Cup Air Race.
Yellow markings were cut from tissue and glued over the basic blue finish. The model’s empty weight is 25 grams without landing gear. Eric achieved these striking results without the benefit of an airbrush.
Resources and links
If you have spare time, check out Chuck Glider’s Model Aircraft Jotter web site. As the name implies, the content is heavy on Hand-Launched and Catapult Gliders, but other aircraft types are included. There is a particularly fun video of trimming flights on a Senator rubber-powered design.
Indoor fliers will be happy to know that a high-quality winder is again available. Tim Goldstein of A2Z Corp is producing a new winder with dual outputs: one is 20:1 and the other is 10:1. The case and crank are CNC-machined from aluminum billet. The winder features seven ball bearings, is hard anodized, is laser engraved, and features an integrated receiver hole for a mounting foot.
The winder uses the same gear system as the Wilder Winder, which was made in two versions: 20:1 and 10:1. I have a 10:1 version, and it easily winds any of my outdoor scale models. — MM
Sources
- BMJR Model Products
(321) 537-1159 www.bmjrmodels.com
- NFFS Plans Service: National Free Flight Society
- Penn Valley Hobby Center
(215) 855-1268 www.pennvalleyhobbycenter.com
- Paul Bradley plans
- Chuck Glider
http://chuckglider.blogspot.com
- A2Z Corp
(877) 754-7465 www.a2zcorp.us
Transcribed from original scans by AI. Minor OCR errors may remain.
