Is there any things to do, or watch out for, when building 4 star 40 kit. just wondering cause i read a post where one guy built 2 right side wing halves, ive thought about this ,looked over instructions cant figure how this could happen, any way any sugestions would be greatly appreciated. I just finished the right side wing half structure only.

With the 4* being my second kit building, I found it much easier to build then my Tower Trainer 40. I also found that the instructs that comes with the Sig kits are much more better then the Tower Trainer instructs as well. Just follow the instructs and you will not have any problems. There is also a link on this Forum about some neat modifications with great details you may want to look at as well. I am doing my 4* with the mods. Below is a link to the guys site with all the modifications. He is very easy to email if you have any problems as I have on a few occasions as well.

Modifications by Tom Pierce

GOOD LUCK with the 4*

R Sprinkel,Thanks for info,do you know how you can mistakenly build two right wing halves, would like to know in future kit building so i dont make same mistake. Maybe some one will chime in on this.

As soon as you don't need the plan for the wing you are currently working on, GET RID OF IT by putting it somewhere else. Immediately get the plan for the second wing out. This way when you start building your second wing, you won't accidentally be using the wrong plan.

Also, don't change the dihedral on this plane, as pitch and roll coupling will be adversely affected. Get a nice Sig leaf-spring tail wheel bracket to jazz up the tailwheel. Keep it light.

My advice: pay attention to the engine thrust...it should be neutral or slightly erred to the right. Put some toe-in on the landing gear, and use a soft wheel for the tail if you fly from asphalt. That tailwheel bracket makes an aweful fingers on chalk sound if the tailwheel is hard and somewhat loose when rolling on a hard surface.

Other than that, I LOVE my 4-star 40 with a 46FX.

This is one plane that flys great built exactly like the instructions say! With a 46FX it is fast and strong when you open it up but it slows down quickly when you get out of it, and you can do any maneuver you want at half throttle if you like. Best of both worlds. Landing is a breeze. Have fun!

I'm just finishing my 4 star 40. Almost ready to cover and install radio gear...

I went with the sheeted turtle deck as recommended on Tom Pierce's web site. One major improvement I discovered when sheeting the turtle deck is to use three 2" wide sheets of 1/16" balsa instead of two 3" wide pieces. By using three pieces I was able to keep the seams off of the very top of the deck, where the bending stress tends to crack the seam, (I found). I also found that the CA seams don't bend as easily and smoothly as plain balsa. It took me three tries using two 3" wide sheets before I figured this out. Luckily my LHS is very reasonable on balsa prices. Burned more $$$ in gasoline than splintered balsa.

My two cents worth,

Fever

Scott, You end up with two right wings if you mistakenly build both wings over the right side plan. It is just a stupid thing "other" people do!
You can also build two right fusalege sides. That happens when you glue the wing doublers on the wrong side. Now I've done that. The plans for the Four Star are very easy to follow. Mine is very aerobatic with an OS 32.

Tom

I just spent a few days getting my ST GS40 powered 4*40 ready for this summers club races. It is 6 yrs old and never been dingied.
My big change was mounting the ST 40 on the bottom of the engine mount. I couldn't access behind the firewall to change the mount location so I put the engine on the bottom. One allowable modification to the 4*40 is dropping the engine 1/4" below the specified mount location to avoid a drop in rpm resulting from a high G turn. At about 15,000 rpm my ST 40 would drop rpm very slighty when pulling out of a turn especially on the last 3 or 4 laps of a 10 lap heat. The only changes I would recommend would be to make sure the stringers behind the canopy are hard balsa and increase the span of the hole in the balsa piece under the engine. I don't see a problem with the landing gear other than weight however we are not allowed to bore holes for weight reduction and make sure your aileron linkage is tight - don't use metal fittings - way to sloppy.

Beef up the landing gear mount. It's terribly weak. First rough landing-- and your wheels are going to come off.

Use some lite ply and put it in front of the blocks. A piece the width of the fuselage and about 2" long is fine. Or you could even put in a piece to cover the entire area in front of the landing gear blocks. However you do it,, put some light ply in front of the blocks and then put triangle stock on all the surfaces. Use 15minute or 30 minute epoxy here.. The longer set time on the epoxy will allow it to soak into the wood for a stronger bond.

I even drilled 1/8" holes through the fuselage sides and into the landing gear blocks. Then pin it into place with dowels and epoxy. 2 dowles on each side is fine-- but you still need to put the lite plywood up front and spread the load out into the fuselage.

Ramcharger
increase the span of the hole in the balsa piece under engine?
What & where are you talking about , I looked in manual didnt understand where you mean. Please explain.

There is a piece of balsa or maybe its lite-ply under the engine/tank called "FBF". It has a oval shaped hole just in front of the firewall. After it is installed increase the span of the hole for better engine cooling, provided you mounted the engine a 1/4 inch lower than the plans specified. Some cut it off at the firewall.

Ramcharger I got cha !!! Thanks for clearing that up .

This was my second plane way back when it first came out. Wound up building another after planting the first one. Used a Fox 40 standard. Also had to trim the nose a bit to make it fit (didn't know about long engine mounts then).

They are right whe they say to reinforce the landing gear mount. Was doing touch and goes once, wiped off the gear and and slid along the ground for a couple of feet. Pulled on the stick instinctevly, and the engine was still going! Went around and bellied it in fearing the battery was gonna drop out.

John