Received a Sig Banshee kit

[John Fitzgerald]

I may not start on it right away, and may only do a piece here and there for a while, to give time for changes and adaptations.  My last model was built too fast, and some things I could have done better were not. I am going to carefully plan several modifications before proceeding.

Here is my list so far of the things I have thought of.  There may be other things I need to consider.

The engine I am strongly leaning toward is a Tower .40 (unmodified) with a Neumann CL venturi and OS NVA through the venturi (already have it) has tongue muffler
I want to move the wing forward about 1.5"
Extend motor mounts back to the wing
Add a 1/4" balsa cheek cowl
Use aluminum landing gear from a wrecked R/C model I have for parts (not my wreck)
Reinforce the bellcrank mount and use a 4" bellcrank instead of the 3" with the kit
Add tip wt box and adjustable leadouts
Add brass tube bearings for flaps and elevator
"Bulletproof" the push rods and horns, if necessary...need help on this.. I have some aluminum horns I made.


Other than the above, I don't want to do anything that will change the basic shape of the plane.

Ideas?

[EddyR]

Do a search on here, Cut 2" off the nose. They came out nose heavy with a Fox 35 on them
Ed

[Dennis Moritz]

Or move the wing cut out forward 1" to 1 1/2"(?). Nose is too long. I've run a lot of those Tower engines as well as FP40s. The timing and measurements the same. The Tower40 modeled on the FP40. Pieces interchange. I think the Tower 40 is a better engine. A chrome vs. nickel liner. Also deeper head fins. I've used a number of Tower engines for years. Compression is still outstanding. I'd put in one or two extra head gaskets. When you're finished and ready to run the engine you can look up the various opinions about how to set up Tower 40s/FP40s. I'm fond of Lee Venturis these days, .272. Lee uses a longer spout. Which I THINK straightens the airflow some. Making the run more consistent. The stock venturi is a .283, the .272 is easier to tune into a sweet power band. Banshees and Twisters are very similar. Difference is the long nose on the Banshee. With a shorter nose it should perform the same as an equivalent Twisters. Twisters are the best flapped profile intro to stunts planes around. Still. Very easy to set up and make work. Get help trimming, if you can. My last Twister was a dog until a top flier club member figured out some fundamental issues, I was not aware of. After the trim session, plane was lively and competitive. I resisted building a Twister/short nose Banshee for years. A contrarian. Friends started chanting Twister, Twister, Twister, whenever I showed up at the field. So. I. Finally. Built one. I am now very fond of these simple birdies. Do various Fancheriz-ing mods, if you feel up to it. Look up Fancherized Twister. These improve things some.

[Brett Buck]

I may not start on it right away, and may only do a piece here and there for a while, to give time for changes and adaptations.  My last model was built too fast, and some things I could have done better were not. I am going to carefully plan several modifications before proceeding.

Here is my list so far of the things I have thought of.  There may be other things I need to consider.

The engine I am strongly leaning toward is a Tower .40 (unmodified) with a Neumann CL venturi and OS NVA through the venturi (already have it) has tongue muffler
I want to move the wing forward about 1.5"
Extend motor mounts back to the wing
Add a 1/4" balsa cheek cowl
Use aluminum landing gear from a wrecked R/C model I have for parts (not my wreck)
Reinforce the bellcrank mount and use a 4" bellcrank instead of the 3" with the kit
Add tip wt box and adjustable leadouts
Add brass tube bearings for flaps and elevator
"Bulletproof" the push rods and horns, if necessary...need help on this.. I have some aluminum horns I made.


Other than the above, I don't want to do anything that will change the basic shape of the plane.

Ideas?

   Moving the wing forward is certainly the right approach to the CG issue.

    i would consider changing the doublers to either 1/32 or even 1/64 ply, but extending to well behind the wing (terminating in an ellipse). That will beef up the are right behind the wing that tends to give up the ghost in even the mildest crashes. It will be heavy but worth it. It's not like you are going to lack power.

    If it was *mine* I would replace the tail with a bigger one, but what you are doing amounts to a "Fancherized" Banshee and will help considerably over the original. i also question the yaw stability with such a powerful engine and would add something to add to the yaw restoring force. Of course I would also design a new airplane from scratch, so it does defeat your purpose!

    Make sure and round off the LE of the wing as much as you can.

    Brett

[Dennis Moritz]

For the Tower 40/FP40, I'd make a rigid nose. I have used 5 ply 1/8" doublers on these planes when powered by one of these engine. I'd probably sandwich carbon fiber between the doublers and fiberglass wing, fues joint at the lead edge going back about half an inch. Brett's advice no doubt works for .25 sized engines. But I have not used them on Twister sized planes. Tongue muffler, also a good idea. Much less weight.

[John Fitzgerald]

I have a .25 FP. It's on a well used ukey.  Thought it might not have enough power for a banshee.  It has a tongue muffler too.  I do not like underpowered cl planes.

[john e. holliday]

You should have gotten a wing rib kit with the full size plans and done your own thing.   

[Ward Van Duzer]

I've built a fair number of FP .40 profiles. You may find my nose construction a little different, but it looks good, and it works!

On the out board side I use Frank Tiano's Mighty Lite 1/8th inch plywood. This is NOT lite ply! But it is strong, and lighter than 5-ply.

Inboard, no plywood, rather a 1/2 in. tripler back to the mid-point of the wing. Sand in a taper where it flows into the fuselage. Note, this provides a 1 inch thick nose/wing jount. Epoxy, of course. You can hollow out the area of the tripler ahead of the wing joint, and fair it into the spinner, and add a lower "scoop" if you choose. It'll also hide those ugly "Tee" nuts from the Motor mounts! You can sandwich in some C/F if you choose, but I really never have.

I'll see if I can't scare up some pics...


Ward

[John Fitzgerald]

Brett:
I am interested in how you do your "bulletproof" ball end pushrods, and materials required to do a set.
Thanks.

[Clancy Arnold]

John

Look at the January 2012 issue of Control Line World magazine starting on page 52.

There are detailed mods that Jack Sheeks recommended to be made to the SIG Banshee kit. It also includes the additional mods I incorporated in my Banshee(ks) and a reduced size copy of the kit plans showing the changes Jack drew on them.

Clancy