Sunday 24 March 2013


MULTIPLE WING RIBS WITHOUT USING PINS.
by Bob McKenzie.

How many times have you made wing ribs by stacking and pinning and have the stack flex or the pins dig into the bandsaw plate and going off line?

Try this for a tapered wing. For this example, a Top Flite Nobler.....

As another member of our little group was also constructing the Top Flite Nobler, I offered to make a rib set for him, as all it would need would be to laminate some extra sheets and still only make use of the bandsaw once.

I cut and pasted paper templates of each rib size onto a suitable size sheet of balsa to maximise the number of ribs then cut 3 more blanks of each size.

Problem! As each rib stack consisted of only 4 pieces of 1/16” balsa, pinning was out of the question as small stacks of 1/16” pinned together do not remain firm and you have to cut the pins flush with the balsa to stop them snagging on things (which doesn't work – they still snag!).
How could I hold them firm enough to cut to the templates and accurately cut L.E. and spars?

First, I aligned each set of 4 sheets and applied super glue at each corner. Next I drilled a 1/4” hole in the centre of the lead out cutouts on each rib stack. A drop of super glue was placed in each hole on each stack. After the super glue had set, each stack was trimmed to its template, a final sand to shape and the L.E. notch and main spar slot were cut using a bandsaw.

If you have a small bandsaw like me, (a GMC 150), it would be best to make mirror images of the paper templates to allow the ribs T.E. to face the right hand side of the bandsaw so they don't foul on the relatively narrow throat of the bandsaw. I had to cut the spar slots on these ribs using an Exacto mini saw. If you have a larger bandsaw, no problem.

To separate the stacks of ribs when you are finished, cut out the leadout slots. I used an endmill to drill neat holes at each end of the slots then cut the remainder with a knife. See illustration 4.

This method could be used also on parallel chord wings.

                                           

Wednesday 20 March 2013


Owen's 38 Special all painted up and ready for a test flight. Powered by a Super Tigre .34.





Thursday 14 March 2013

Lyal Cameron has modified one of his combat wings and turned it into a fast stunter.
 Powered by an ASP .15




Monday 11 March 2013


It's a little late for a report on the Nats but here it is for those who are interested.......



    Report On 66th Australian Nationals Aerobatics Events by Peter White.

The Nationals were run on one of the sports ovals at the Alexandra Park Sports Complex in Albury, a regional city on the border of Victoria and New South Wales, from December 29th to January 3rd. The flying surface was well mown if a little undulating and showing the effects of the hot dry weather the area has been experiencing over the summer period.
Temperatures at the beginning of the week were in the low to mid 30s C and crept steadily up to the very high 30s as the week progressed. The wind, for a change, was not really an issue apart from an occasional rough patch that came through. It tended to drift around in the mornings catching some flyers unawares and requiring constant repositioning of the judges but in general, as each day wore on it became more insistent but quite manageable.
F2B was flown over four rounds with the best three scores being counted. Advanced and Expert were run separately and alternated on each of the four days giving both classes equal exposure to morning and afternoon conditions.
All of the events, F2B, Classic and Vintage, were ably CD’d by Frank Battam while Alan Matthieson-Harrison carried out all line pull duties for the week. Score tabulation was very efficiently handled by Susan Hegarty and Steve Vallve did the bulk of the score sheet running and posting of scores .... our thanks goes to these hard-working people and all others who chipped in at various times.

ADVANCED.
A field of seven flew in this event with Robert Graham taking out first place running an electric powered SV 11 fitted with an Arrow Wind 2832 with a Phoenix speed controller and a Hubin timer. Robert put in some good flights enabling him to win by a comfortable margin. Second spot went to Steve Bakac flying a Turnigy 4S 2650 powered Europa with ZTW controller and KR timer. He flew some neat manouvres but didn’t seem to be up to his usual standard. Peter Koch guided his ex-Doug Grinham Jazzmate/Stalker 61LT combination into third place with some well flown shapes along with his share of missed bottoms and intersections.
Newcomer to Nats competition, Adam Pogue, flew a Saito 56 powered ex-Reg Towell Seafire. Adam had his four stroke starting technique sorted out and the motor well tuned. He tended to fly quite high, not being totally familiar with the model.
South Australian “retread” from the 60s, Jeff Prosser, put up some well shaped manouvres with his electric powered modified Legacy running an EMAX motor, ICE LITE 50 speed controller and Hubin FM 9 timer. Bottom heights and 45s were generally good and flown confidently. Jeff is one of a group of SA fliers who have enthusiastically taken to electric powered aerobatics.
Tony Clifford had his OS LA 46 running consistently in his neatly built scaled down KA-10. Heights were varied but with increasing confidence, Tony’s flying is improving.
Nats regular Don Keyssecker, flying his OS LA 46 powered Vector 40 put in some reasonably good patterns, missing some intersections and bottoms along the way.
Judges for the event were Joan McIntyre, Russell Bond and Peter White.
EXPERT.
A total of seventeen in Expert class flew in front of judges Joan McIntyre, Don Keyssecker and Dave Simons. Of these, Russell Bond and Bruce Hoffman ran electric power – Russell with a Plettenberg 25-10, ICE LITE 50 speed controller, Hubin FM 9 timer and Bruce with an Arrow Wind 2832, JETI 66 speed controller and Igor Berger timer. Both set-ups ran flawlessly, producing an abundance of power and were totally consistent.
Almost one third of the field was made up of Jatsenko models. Frank Battam ran a Yak 55/Retro 76 combination while Peter Anglberger and Mark Ellins each flew a Retro 76 powered Classic 111. Eventual winner, Mark Batty, put his Shark through four precisely flown patterns to top second spot by a mere four points and show us how it’s done. Most of the Retros had what appears to be a characteristic rattle in parts of some manouvres although this didn’t seem interfere with their performance in any way.
Fitted with a side mounted Stalker 66, Barry Frederickson’s Classic 1 appeared to be handling well. Barry is capable of flying precise square turns with generally good heights.
Doug Grinham ran a Stalker 66 in his O/D Starcraft. In its original form this motor, similar to many other Stalker 66s, would not run symmetrically unless it was side mounted. Doug has had some mods done to the crankshaft timing resulting in a powerful, consistent running motor that is now quite happy to run in an inverted mounting situation.
The lone four stroke in Expert was Reg Towell’s Saito 56 fitted to his Miss America. Reg, as usual, put in good flights consisting of neat manouvres with many accurate heights and intersections.
Paul Turner’s Wind Wonder/Stalker 61LT suffered a prop strike on the first round takeoff and for various reasons Paul elected to not fly the remaining rounds.
Flying a Muggleton 40 powered Sukhoi, James Batty claimed third place with the same model that his father, Mark, had used to win the 2001 and 2002 Nationals. The Sukhoi, in James’ capable hands, flew as though on rails, having been finely trimmed over many years of competition flying.
Tony Bonello’s Firecracker featured a standout finish and a superbly running Super Tigre 60 which, with its deep exhaust note, gave an impression of power and smoothness as it four cycled through the pattern while Brian Eather’s O/D Firecracker performed very well, its Stalker Pro Series 61 putting out a great deal of power to haul the large model around with little effort.
Steve Masterton’s ST 60 powered Firecracker flew well, appearing to be stable and well trimmed but despite flying some good shapes he lost valuable points on wandering intersections and heights.
Joe Parisi took out second place flying his PA 75 equipped Hot Pursuit. Joe was running the PA on a long Eather pipe giving a similar run to that of a muffled motor with lower revs and a lower pitched exhaust note .... with the power that is available, the model is very positive in all parts of the pattern.
Sporting yet another eye catching paint scheme was PJ Rowland’s piped PA 75 powered modified Thunder Gazer that was flying well and scoring accordingly until landing gear failure caused damage to the underside of the fuselage and wing. In the two flights he made, PJ had scored third highest for both rounds, which must have made his exit from the competition all the more disappointing for him.
A lack of preparation on my part along with broken starting leads, lost wingtip weight and a lazy Stalker 61 all contributed to a lack-lustre performance from my GEO-XL and its pilot. A small number of flyers, self included, were caught out by the heat and humidity with missed needle settings, unsuitable props, etc.
When the dust finally settled, it was decided that father and son Mark and James Batty, had taken out first and third places, surely a first for our Nats, separated by Joe Parisi in second spot while Brian Eather sat in fourth place by two points and Russell Bond a further six points down. 

Peter White.