Back to Basics

Getting down to the fiddly bits this morning, one thing I tend to forget is to drill the wing bolt positions before fixing the attachment plate. The threaded inserts are a lot easier to fit than standard "wind 'em in or whack 'em" spiky T nuts. One advantage of threaded inserts is that the hex driver holes make it easy to locate the wing fixing screws when attaching the wing. The attachment plate is angled using a slice of TE section as a guide, hopefully this will be parallel to the top surface of the wing and will allow the use of flat nylon washers under the wing screw heads
I looked on the SIG USA website to see if I could get some info on the Kadet. The model I'm currently building isn't available, but the Kadet lives in various sizes in kit form or ARTF. The redesigned Kadet is now the Kadet Senior, and is a bit bigger.I was interested to see that the power requirements are quite modest, so My original thoughts of using an OS FS .52 made me realise that the model would be overpowered. I have an OS FS .30 that I think might be a better choice, and being less powerful, perhaps I can get away with a three channel set-up. The original Kadet was three channel, and although I have the official plan for the aileron conversion, it does look very much like an afterthought.

Looking good Brian, if it is overpowered you can always throttle back, better than being under powered, personally I would see how the C of G works out and then use the biggest engine you can get away with, on the subject of ailerons, if you add them it will give you more control in the wind

I'm with Chris, it will definately have better control authority with ailerons and be nicer to fly, depends if you want to go full retro or not!

Brian wrote: My original thoughts of using an OS FS .52 made me realise that the model would be overpowered. I have an OS FS .30 that I think might be a better choice, and being less powerful, perhaps I can get away with a three channel set-up. The original Kadet was three channel, and although I have the official plan for the aileron conversion, it does look very much like an afterthought.

According to SIG info your FS 30 is below the recommended min power. your 52 is mid range.

re - 2-Stroke .29 - .40 cu. in. (4.8 - 6.5 cc), 4-Stroke .35 - .65 cu. in. (5.7 - 7.4 cc)

Thanks Chris, Jon and Kevin for your comments, the model I'm building is the original 1972 (?) design, it appears to have been updated in 1976 when the aileron mod was incorporated. The present SIG offering closest to the Kadet I'm building is the Kadet Seniorita which is 63" span, the recommended engines are, 2 stroke .15-.25,
4 stroke .21-.35, hence my opting for the OS FS .30. But as you say, the model doesn't have to be flown at full throttle, and there's the option of a finer pitch prop as well. I suppose flying a three channel model is a bit limiting, but this one is very light compared with more modern designs, so perhaps it would be a bit of a handful in windy conditions even with ailerons. At the moment there's no final decision as the firewall hasn't been drilled yet. Thanks for your interest, keep watching this space!

If you accept that it is going to be a fair weather model then low power and rudder only will be fine. But it will be a handful landing a Cashmoor when the wind is blowing from the north because it simply will not respond quick enough when it catches a gust on finals.