Test005

Hi
The Kadet Senior seem to have a built up fuselage from 'sticks'.
From my point of view it looks kind of weak and not sturdy at all compared to a fuselage from lite-ply + doubler.
Any comment on this?

Also, would a 52 fourstroke pull the Senior ARF around at moderate throttle?

Siefring

I'm sure you can design and build a fuse with balsa sticks that is lighter and stronger then with lite-ply. It's just a matter of sizing the wood right and properly reinforcing with bulkheads, gussets, and cross pieces.

Go to the scratch building forum and read some posts on wood selection. Most of the scratch builders do not recommend lite-ply for anything! This is not to say that lite-ply is terrible. Lite-ply makes a very convenient and quick build for a box-like fuse. It is also easy to mass produce fuse pieces in lite-ply. That is why the kit (and arf) manufacturers use it.

Carl

staggerwing

My Feedback: (5)

If built carefully the Kadet Sr. fuselage is very strong. Note that it consits of a group of triangles and triangles are inheritently strong. With the Kadet you need to take the time to make sure all of the angles are correct and all the ends are squared off so that they make full contact with the next peice. If done right, it will be lighter and stronger than lite ply.

If you plan to use the Kadet as a trainer then the .52 will be okay. If you want to do more with it, I'd recommend an .80 or .91 four stroke. I've built a lot of Kadets over the years and they are fantastic flyers. Add ailerons and take most of the dihedral out and you will have a ball.

Rich

Siefring

I have not built one yet, but have been seriously considering getting one. I agree with Rich. The plane IMHO wants ailerons and with ailerons the wing dihedral should be reduce. The ARF version already has both of these modifications.

If I were building one I would go with an 80 four-stroke. If you have a 52 sitting around and want to save money, go ahead and use it. You can always put in something bigger later and re-balance the plane.

Carl

Tall Paul

On the plain-vanilla Kadet stick fuselage, if you put diagonal braces on the top and bottom between the crosspieces, and a fore-aft longeron on the outside each side about 1/2 way up the side, the aft fuselage will remain intact after the crash.
If you do't crash you won't need this added stiffness, but it is stiffer anyway, so it's a good idea.
This one is about 10 years old, hasn't crashed yet..

goboto

I built the Sig Seniorita last winter. It's the baby sister to the Senior. I kit-bashed it and reduced the wing dihethral and added barn-door ailerons, then tucked a Saito30 in the nose and covered it in red transparent Ultracote. For the size, many think it is a ".40" size plane, and they are always very surprised at the small engine and how well it flies. My instructors were disapointed that I got my wings so quickly, because they couldn't get as much time flying my bird as they would have liked. With a transparent covering, the stick fuse draws admirers from a distance, bypassing the usual HobbyCo trainers.

Don't be afraid of the stick fuse, it's remarkably strong and very light weight. The covering material adds considerably to the strength. You don't really need to cross brace the fuse. Just build it following the plans. This is an old design but a true classic winner. Just take the time and care to make each joint to fit tightly. You know, measure, measure again, cut, fit, sand, fit, sand, fit, glue. If you make a piece wrong, start over to get it right. The scrap piece can be used elsewhere.

The only other thing I'd recomend is to up-grade the elevator push-rod. When I was breaking in my engine (on the plane) I noticed the elevator push-rod was vibrating a lot. I was concerened that it would bend, and not give me full authority on up-elevator, when I would most need it, so I replaced it with beech wood dowel and I'm happy with that.

Tall Paul

The Seniorita is very happy with a .25 or .28 2-stroke... or like this one, a Speed 700 or geared Speed 600 electric..

rthalls

My Feedback: (63)

what size float and engine for a sig senior ?? thanks

B.L.E.

The longerons on the Kadet are spruce, the triangular bracing is balsa. It's plenty strong. Light planes don't need to be strong. The heavier you build them, the harder they crash, and the plane breaks anyway.

TCrafty

I just had an incident with my Senior. It was dead-stick landing and wind caught it from the side. I couldn't correct for it in time and splat. My dad, the builder of the family, tore the covering off and said that the glue (ambroid) was so old that the peices would just fall out once he removed the covering. That was the only thing holding it together. We were both amazed because we knew how much I threw that plane around in the sky. it is at least 10 years old. built from a kit with little dihedral and ailerons. Had a .91 OS 4-stroke on it with a 15X8 MAS prop. GREAT combination!

Tall Paul

Senior Kadets use 48 inch floats.
I use the 27" floats E-flite has for their J-3 on my Seniorita.