Back to Basics

Brian Jackson wrote: I have to be careful with the spending Simon, I've got to save up for a TV licence, whatever that is.

:lol: :whistle:

Now that the Panic has been patched up and has had a few flights, its high time I got back on to the SIG Kadet. The sewn hinges were fixed to the ailerons first, then trimmed to length. The method I use is to attach the top part of the aileron hinge to the top of the wing first. The aileron is then rotated so that it lies on the top surface of the wing, then the final part of the hinge can be attached to the aileron spar. To get a successful bond using the "iron on" method, the temperature of the sealing iron needs to be adjusted to a temperature high enough to completely melt the film of PVA. If the temperature is too low, its all too easy to think the covering has bonded, where in fact is is only lightly "tacked". The Polyspan covering is OK at high temperatures, and the method of applying it is pretty much the same as heat-shrink film, apart from the higher temperature, and the need to move the iron quite slowly to achieve a good bond.

Nice days will be getting fewer now so it seemed like a good idea to get the wing covered. The fuselage and the rest of the bits can be done in the relative comfort of the shed. The Polyspan went on with no dramas at all, and the wing is now in the shed and oozing the heady smell of cellulose dope. I think the resident spiders will be a bit miffed by the smell, with a bit of luck they'll go find somewhere else to make a mess with their webs.

There was a slight delay in finishing the Kadet's aileron covering. I was distracted by a calm morning and the need to go and try to fly my old Lazy Bee from the lake at Longham. The LB is a three channel model and I'd completely forgotten to set it up with the rudder and elevator on the RH stick. The model taxied around nicely, I lined it up into the very gentle breeze and it lifted into the air very quickly. Unfortunately, before I could get it high enough to trim out, the Bee started to roll to the right, I eased in a little aileron and began to close the throttle. Unfortunately the more aileron I applied, the worse the roll to the right became. The crash was a non event, the floats parted company with the fuselage, as designed, and floats and model were left drifting peacefully on the calm water. Fortunately a fellow flyer had a Graupner SeaBee, he used this to push the floats and finally the LB to shore. The final recovery was made by another brave chap who waded into the edge of the lake and retrieved the, by now, waterlogged LB. I flushed all the electrics with alcohol, and left things to dry out for a couple of days. I was surprised to find that everything worked perfectly. With the Rx re-bound, RH stick configured for rudder and elevator, three sets of rates and 20% expo dialled in, I think it might fly a little better next time. The LB has had a couple of extra coats of clear dope, and something I completely forgot was the air outlet in the bottom of the fuselage. This is now covered with a doped on patch of LiteSpan.
Now I'll get back to the Kadet, until another calm morning arrives.

The Kadet's fuselage was built with too much enthusiasm and not enough forethought. Consequently, mounting the fuel tank and nosewheel steering hardware meant hacking the front of the fuselage about. To avoid this unpleasant task, I used the front bulkhead as the main support for the engine bearer, nose wheel mounting and fuel tank. This assembly slides in to the front of the fuselage and sits between the first and second formers. I am now seriously short of bits of scrap balsa, so any more mistakes or additions and I'll need to think about getting in some more stock. Once again the build has been delayed by the lure of flying the Lazy Bee from Longham Lake and the Panic at Cashmoor.

The Kadet has a full set of servos fitted at last! I've used two with a "Y" lead for rudder and nosewheel steering, bit extravagant, but the servos are quite small and I didn't want to overload just one servo for rudder and steering. Made up the U/C with the correct diameter wheels, finding a couple of suitable washers was fun and had me rummaging in odd corners to find four. Very time consuming as I kept stopping and looking at the stuff I'd turned up and trying to find somewhere "tidy" to keep it. I wondered whether to use balsa push rods for elevator and rudder, but I'm not keen on that method, so I've used a pair of Sullivan snakes. Bit gaudy with the red outers but I'm sure it won't notice when the Kadet finally gets into the air. Fitting the servos and control runs took most of a day, although it didn't seem that long. Looking at the jumble on my "Ironing/Building Board", its a wonder that I got anything built at all. The tail plane/elevator, fin/rudder are covered in Polyspan and have three coats of clear cellulose dope. The blue trim is lightweight tissue, applied damp and fixed by slopping on plenty of thinners. When dried out, a final coat of clear dope. One thing has been very helpful in screwing bits in place is a kit of 2mm self tapping stainless screws, hundreds of 'em in various lengths, ideal for control horns etc. Funny thing, I bought them from an Irish website, but the package came from China, odd that.