MyNeed4Speed

My Feedback: (2)

All, I must be doing something wrong ... wondering if you can help!

I've got a Funtana 40 with a Saito 91 on the front, and I'm trying to balance it at 5 5/8" from the leading edge of the wing, along the fuse, per the manual. I'm balancing it right side up, as the manual does not specifiy to balance it upside down.

I've got the battery pack under the tank. The receiver behind the tank. Using JR 537 for the elevator, and a Hitec 635 metal gear for the rudder.

If I put 5 oz of lead on the engine mount, I can get the thing to balance. It's seems to be tail heavy.

That just seems wrong, given what I've read on the site here. Should balance without adding weight.

Any ideas? Should I balance the beast upside down?

Randy

JoeAirPort

My Feedback: (41)

They tend to be tail heavy, I've had two and they were both like that. The best solution I can give you is to go pull pull on the rudder. That 2 oz MG gear servo is heavy on the tail of that ARF. If you move that 2 oz towards the front it would easily cancel out that 5 oz you were adding in the nose. Take out the rudder servo, set the servo on different places on the fuse and keep trying to balance it. When you get the CG to 5 5/8 that's where the servo should be mounted. The Funtana 90 with the Saito 100 has the same exact problem. You need to put a Saito 180 on the nose of the Funtana 90 to balance it with all the servos in the tail.

What kind of spinner do you have? If you use a Tru turn Ultimate style spinner and prop nut adapter usually will add an ounce or two to the nose.

johnyh

I had to put a load of weight up front on mine. Even with the Saito82 I've got ample power.

cwhite

My Feedback: (42)

I had that problem with my Saito .82 and found out that mine flies best at 6". My plane didn't become a decent 3d plane until I moved it back to 6". No weight in front, both servos in back and I pulled the battery out from under the tank and placed it behind the tank. Trust me!! This also improves the wacky elevator problems. Does everything better at 6"-6 1/4".

Fubar-One

My Feedback: (1)

Describe the "Wacky elevator problems" if you would? I have one of these with an OS .70 and it is nearly impossible to fly with the elevator at full throws. I thought it was just me.

JoeAirPort

My Feedback: (41)

You can only do stalled maneuvers at full 3D elevator rates. Flat spin, walls, elevators, parachutes, slow speed snap roll. Many do tip stall between 20-40 degrees elevator. Just the design. If you pull full up or down at 3D rates you gotta do it quickly to avoid the middle zone (20-40).

JoeAirPort

My Feedback: (41)

Where does the CG end up without the 5 ounces? It's true that if it's close to 6 inches it's fine. Between 6-7 inches it starts to climb inverted at neutral elevator. It drags the tail around and it's not a lot of fun. I've actually had it at 7 inches. It did some crazy stuff.

MyNeed4Speed

My Feedback: (2)

OK, tonight I put a higley heavy hub on as the prop nut, and added 1 1/2 oz to the engine mount. balances now at about 5 7/8" ... should be good enough to get me in the air to play with the CG a bit. I don't have the cowl on right now, and the prop is just a good ole 13x8 APC. Just for grins, I put on a 15x4 APC prop and the cowl. I think I can get the lead on the engine mount down to 1/2 oz, maybe less, and hold the CG at around 5 7/8".

Checking the prop clearance with the 15x4 ... not much room between the ground and the prop. Might need to change out the gear ...

Bodge

Seems like a slight discrepancy here... Funtana 40 - Saito 91 (40 - 91???) Maybe that's why it doesn't balance...?

JoeAirPort

My Feedback: (41)

If your theory were true then it would be nose heavy right? It's tail heavy. The Saito 91 is a perfect match for this ARF.

Bodge

Yes, excuse me for being facetious. It does seem, however, that someone at the design stage hasn't done his sums right. I've read quite a bit about balance issues with this model.

cwhite

My Feedback: (42)

I wouldn't suggest adding weight to the prop shaft. It seems like every time I've tried that I've lost too much power. I would rather add weight to the firewall. I have no extra weight added to mine with a .82 and battery behind the tank and it balances just over 6". I would think with a .91 you shouldn't have to add weight. I would rather have the plane slightly tail heavy than add weight and I think the plane flies better at 6"-6 1/4" than at 5 7/8". It also lands easily at the 6" to 6 1/4" range.

JoeAirPort is right on about the elevator. In my case I think the elevator is a lot more manageable with the cg further back.