MinnFlyer

My Feedback: (4)

I need a favor from someone who owns a STOCK Sig 4* (40 or 60 but with no major modifications)

I would like you to take two pictures of it: a direct top shot and a direct side shot, so that I can create an illustration similar to the Ultra Sport below.

Thanks!

ScienceisCool

My Feedback: (1)

Can get you one later tonight if no one else beats me to it.

MinnFlyer

My Feedback: (4)

Great!

mclina

Mine's not stock, but does this help?

MinnFlyer

My Feedback: (4)

Perfect!

Thanks!

Minnreefer

Are you building one for yourself?

MinnFlyer

My Feedback: (4)

No, Ken was looking for a diagram for trying out color schemes. I was going to draw one for him, but mclina's is just what he was looking for.

RCKen

My Feedback: (9)

And before you ask, yes I may be building one!!! Just not sure when I'm going to start it quite yet. Planning on buidling a 4-Star 120 with a MLD-28 gas engine on it.

Ken

Insanemoondoggie

That should be a good combo Ken.

Mr67Stang

I love mine (4 Star 120) with the Evolution 26 GT on it. The MLD 28 ought to be very nice. I did clip one bay off each wing and enlarged all control surfaces including replacing the aileron stock it came with. And it still flies nice and stable.

RCKen

My Feedback: (9)

I'm planning to cut one bay from the wings as well. Also going to expand rudder and elevator. Iwanted to get a Zenoah 26 (magneto version)for it, but those are getting very hard to find. Italked with Steve Thomas of Bob's Hobbys in Orlando and he has the MLD-28's which he recommended. So I've got Santa stopping by his shop to pick up before he heads to my house!!!! Santa is also got his hands on a 4-Star 120 kit which is also hard to find these days!!!

Ken

Mr67Stang

Well, with the tail feather stretched 1.25 in including adding 1.25 in cap strip/counterbalance to the top of the rudder and .5 inch stretch to the ailerons at the root tappering to a .25 in stretch at the tip a properly propped 4 star 120 hold an impresive hover and can perform all pattern aerobatics. I am still dialing in the right thrust as I had to use a good bit of rudder trim to get a good virtical upline without pulling to the left. I hope my weather clears soon so I can see if the shims behind my engine mount have corrected this.

RCKen

My Feedback: (9)

With those mods to the tail feathers how does it knife edge?????

Ken

DenverJayhawk

can you do the same with a Stik?

Insanemoondoggie

Modding the tailfeathers helps a bunch with knife edge .All the 4 Stars I,ve flown , tuck to the belly when doing knife edge. The best mod you can do IMHO is taking one bay out of the wing , as your planing to do.

ChuckW

Here's what I did to one of my .40 size 4-stars (I've built 3)...

-Enalarged, stick-built tail surfaces with an altered shape
-Sheeted turtle deck with revised angle.
-Wing clipped one bay on each side with rounded tips, stick built ailerons and dual aileron servos. I also cut my own wing ribs 1/16" undersized so I could sheet the leading edge and add cap strips. I believe I changed the rib spacing as well, using fewer of them.
-Side mounted engine with a balsa cowl

If I were to do it again, I would not stick build the tail. I ended up with a nose-heave plane and had to put the battery all the way in the back. That was a 40 size of course, the 1.20 might be completely different.

I think one of the things holding the 4-star back from good knife-edge (the 40 size anyhow) is a lack of good side area on the fuselage. If I were to build another I think I'd alter the turtle deck even more and maybe even change the profile between the canopy and turtle deck to make it a little taller there too. That being said, both of my Super Sportsters are a similar profile and they knife-edge with ease so I could be wrong.

I have mixed emotions about the MLD-28. I have one and it has tons of power at wide open throttle and it will idle fairly well. Transitions and mid-range are difficult to get right though compared to my other gas engines which just seem to run perfect. In my opinion the carburetor is too big for the engine. Of course if you just bury the throttle then it really isn't an issue. Mine is over a year old though so the newer versions might be much better. One inexpensive engine that I am really impressed with is the XYZ-26cc from Hobby City.

Keep the 4-star progress posted, I've never buitl a 1.20 and I'm interested to see it.

Mr67Stang

The left rudder knife edge would go all day long. Right rudder fell on me. I am hoping I will get that fixed by getting my engine alignment right...er correct. I also installed a cable pull/pull rudder system and used two elevator servos relocated to the rear of the fusalage. Not neccisary for balance but nice for eliminating control rod flex. I now have 440 rod instead of golden rod. Oh!, I also reduced the dihedral a smidge using the TLAR method (That Looks About Right).

Mr67Stang

Thought I could add some pictures for you Ken. You should recognize the inspiration for the covering scheam.

Mr67Stang

Sure.

RCKen

My Feedback: (9)

Yes, that covering does look a bit familiar!!! Nice looking plane!!!!

Ken

skyraider71

My second Four-Star currently under construction.

jimmyjames213

My Feedback: (2)

nice plane, i like the tail surfaces a lot, i think ill do something similer on my ultrasport .60 when i build it (Christmas break). i did a flag on my mojo .40 and it lookes ok, plan on paying more attention to detail on the ultrasport

DGUY

My Feedback: (9)

This may sound like a dumb question but if you don't know well you don't know. When you are referring to clipping one bay off the wing where do you do it at. Where they join I assume but you all know what happens when you assume. I have a 4*60 and wonder how hard it would be to go back and make this mod/
Thanks
Derrick

Mr67Stang

No, not where they join. The root ribs ar more unique in that they are trimmed to accept the center sheeting (required for strength) and larger portion of the wing spar as well. Clip an outer bay off of each wing tip. Use a razor saw and trim it about 1 mm outside of the second to last wing rib of each wing. Sand the excess stringers/leading edge/ailerong flush. Simply cap the new shorter wing tips with balsa sheeting sanded to shape or use thicker balsa block and make a custom rounded wing tip if you like. If you find yourself wishing your Four Star was more lively/aerobatic you will enjoy this modification.

RCKen

My Feedback: (9)

As Mr76stang said, cut off the outter bays on the outside tips of the wings.

Ken