Scale Soaring UK

Hi Steve , thank you for the encouraging words. We are having your Australian weather here ! This certainly slows the build with more good flying weather. Here are some photos of the wing spar set up. Luckily they came out weight matched and straight. Now the fun really starts with the wing build.
Regards John.

The right wing construction is started with the ribs glued to the spar box rear and front. A washout taper to 6mm at tip is jigged from the start of the aileron rib. With an MU13 canopy on loan to copy the canopy frame was constructed next. The instrument panel and rear frame are 3mm ply, with the side rails constructed from 1.5mm ply and balsa composite. The riblets are 3mm ply , with 2.5 mm spruce side bars attached. The spreader tube is 4mm od brass tubing which is load bearing on keeping the wings apart. The attachment is with spring clips at the rear and a magnet under the instrument panel. 0.8 ply is used for the skirt sheeting. Just the painting and glazing is left to finish.

Right wing construction basic structure was done, with the trailing edge made from balsa ply balsa composite. Abit of regiging of ribs was required to get a good alignment of the washout . The rear joiner brass box was boxed in with 1.5mm ply. The aileron servo was installed on a removable hatch, along with the spoiler servo. The false leading edge of 1.5 mm balsa was glued. The drag spars of 5mm ×3mm spruce were fitted.The facings are 1.5 mm ply.A departure from the original design was the replacement of the 0.4 mm ply facings between the ailerons and rear wing box with 1.5mm balsa sheet. So the 5mm sq spruce spars had to be positioned further apart to accommodate the balsa facings.The facings top and bottom would still be retained for the continuity of the 0.4 mm ply wing skinning. The wing tips are constructed with laminations of balsa sandwiching 0.8 mm ply. So at this stage the t.e and tip need final profiling and then the ailerons cut out and facings fitted.

John, been watching your build with interest.

Not wishing to be a killjoy here, you might want to consider changing those straight servo extension leads for twisted triples. They might just be fine but twisted will obviate any cross talk between cores and the subsequent servo problems.

I use this:-

https://www.componentshop.co.uk/3-way-h ... 2-awg.html

It works for me.

BC

Thanks for the advice. I will replace with twisted triwire. No point taking a chance. Regards John.

Next the making of the aileron. It is faced with 1.5mm medium balsa from 48 inch stock. The control horn is glass fibre mounted in a box of 1.5mm ply between the ribs. The aileron is fitted and top hinged on 5 "Robart" metal pinned hinges. The wing tip and tip aileron profiles were further blended. The 0.4mm ply facings were added top and bottom, and the 0.4mm cap strips which blend into TE gussets. This scale feature adds considerable strength to a fragile point of the wing. The balsa facings were worked to give a small gap at the top and V section underneath with room for the fitting of an aerodynamic seal. The spoiler box frame is built from 2.6mm sq spruce strip and 4mm section balsa rib doublers. The "letter box" 0.4mm ply surround is glued on. The leading edge will but upto the wing D box 0.4 ply sheeting. The Next job will be the ply root facing rib to fit and blend in with the fuselage. Some more reprofiling of the ribs then the fun of wing skinning begins. I will be using J G' s method (See Ghost Squadron excellent video). Regards John.

Chris,
I understand that twisted wires are principally used to reduce Mutual interference from external radiated noise sources.
The idea is that the twisting ensures that all wires pick up the same amount of interference, rather than some being partially shielded from noise coming from any given direction.
The presence of similar noise on all wires means that the differential signal between the wires (which is usually what the device at the end of the wires is interested in) is largely unaffected by the interference picked up.
This type of wiring was often backed in particularly noisy environments with differential signal receivers which were able to virtually totally ignore any interference common to both signal & ground lines.

Note that twisted wires (for Mutual Interference reduction) & ferrite rings (for Conducted interference reduction) were common in 35MHz days when the long aileron etc. servo runs approached 1/4 wavelength, but this is no longer the case with 2.4GHz equipment as the wavelength is 1000 times shorter.
Modern equipment also tends to have for better out-of-band filtering performance.
Peter

Hi Gents what you say makes perfect sense to me. Thanks and on the subject of interference I would be much more concerned about mobile phones on the flight line. I gather they have to be very close to the transmitter to have any affect, however I keep mine in the model park when flying and not on my person. Regards John.

Here we go with some more progress over the last few weeks. The top sheeting of 0.4mm ply was glued on with 6mm balsa rib doublers at joints. All reprofiling of ribs etc were with slivers of balsa soaked in cyano for a durable sandable finish. PVA glue was used on skinning with the hot iron method. Around the tips Aliphatic (yellow) glue was used for feather sanding to profiles. Aliphatic glue was used on most of the structure including the rib caps. The Delux Materials Resin does have a fast grab time if used in 25 deg temperature of my model room. The photo of the root end of the Aileron shows the structure of the balsa facing on 5mm sq spruce boxed by 0.4 mm ply top and bottom. 0.4 mm ply cap strips flair into the TE of balsa 0.8mm ply balsa sandwich. 6mm thick ply blocks were glued to the root ribs to take screw hooks for rubber band wing retainers.The bottom sheeting was then added with rib caps and capping of the cutouts and covers for the spoiler and Aileron servos. The top skin is joined at rib 28 to accommodate the compound curve at the tip. The gentler curve underneath allows a continuous skin to the tip. So next year the balsa leading edge and root rib capping will complete the starboard wing. A HAPPY NEW YEAR to you all.