I have a Big Bingo that I am in the process of balancing. I have a Magnum 180 4 stroke for power. Plans call for up to 160. I need amost 20oz to balance. Does this seem possible? I have the 6v battery mounted as far forward as I can get it. Using a Airtronics 2.4 so the rx is very light. And, yes I did sand as much as I could off the rudder and stab.

Goirish,
20 oz is a lot, but not too much. Especially considering that it's a big plane.

Ken

Yeah, Gene, it seems possible. I don't know if you recall my Tiger 120 setup. I had (still have that plane) with the OS 1.20 AX which is larger than the recommended (.90 - 1.08) and I STILL needed over a pound of nose weight!!!

In fact, a friend has one, put an OS 1.60 on board and STILL needed quite a bit of nose weight to make the correct CG.

CGr.

Irish do you have the ability to either move the engine forward on the mount, or to use a bigger/heavier mount, or even add elastomers between the mount and firewall? A small change with a large engine makes a big difference.

Hey Gene, one more question. Is that Big Bingo a rear-mounted servo aircraft? From my understanding, 1 ounce in the rear means 4 ounces in the nose. If rear mounted servos, moving the servos to the center may help. I don't know... just a suggestion.

CGr.

No it is not a rear-servo mounted setup-

gaRCfieldmotor is about as far forward as it can go. Near the end of mount so it would clear the carb on the firewall.

RCKenIt may be more like 18oz. I was setting a Cinnamon bottle on the bottom of the plane below the engine line. It is a low wing so I was balancing it upside down. The balance point was 4 3/4 from the LE according to the plans.

Gene,
I'd leave it. If that's what it's going to take to balance it then that's what you'll need. You seem to have done everything you can on the plane already.

Ken

I think I have a solution: Move the wing back to just in front of the stab. that way I don't have to add any weight. It will then look like the super concord with that long nose.

Ok I will do that. I wonder how much it would have taken with a smaller engine.

The thing is built with mostly lite ply with a piece of 3/8 plastic water pipe for a leading edge of the wing. It's made like a tank?

Should last forever

Especially if it's too heavy to get off the ground.

Bruce it will sure look good taxing around the field. I think I will weigh it. Let you all know.

w8ye you are correct there is no balsa other than the front cowling.

Bruce It comes in at 14# 6oz. Without being balanced. So close to 16# balanced.

Are the fuselage sides solid wood?? If so, you can cut out some lightening holes in the side of fuselage behind the wing. This removed materials will mean you need less weight in the nose to balance it.

Ken

Yep, that sounds like my Tiger 120. It is made of 'light ply' but comes in there pretty heavy. But the thing has such a large wing that I'm sure it would fly with a rubber band.. 80" span, 1,143 sq. in. The specs say 11.5 pounds, but I imagine it's much heavier than that. I would guess around 13 pounds or more.

Even with that extra weight, though, I must admit that it does fly pretty well. It floats in for landing and landings are very solid... ha.. I guess so, when it loses lift, well, it ain't about to balloon up again.

CGr.

Nope they already have cutouts in them.

Oh, ok. Sounds like you've done just about everything you can to keep the weight off. As long as you didn't leave a tool inside of the fuselage (don't laugh, it can happen. Don't ask ) there's not much else you can do. You'll have to live with the weight on the nose of the plane

Ken

Or you could replace the pvc with galvanized. (Would that be still considered usable weight)?

I would just use what it takes to make it balance properly. If it was a real concern, you could calculate the weight / sq. in of surface to if it was flyable.

Pulled this up from another forum
Specifications
Name of kit - Big Bingo
Manufacturer - ACE R/C
List Price - $179.95
Span - 85"
Weight - 16 lbs.
Area - 1425 sq. in.
Spinner - Tru Turn
Ignition - C.H. Electronics
Pilot - MGA Enterprises
Radio - ACE Micro Pro
Servo's - JR heavy duty
Covering - MonoKote

another post,/. I guess I am not to far out of the ballpark.

both bingos fly pretty much like the other.the bingo 60 is faster on response .My big bingo weighs in at 18lbs.os bgx3500 with a mioki 20x8 prop on 10% byron fuel.the 60 also flies with 10% byrons.These planes are a joy to fly.
I wish some mfg would bring thses two planes back as arfs.

Ken, Gene.. A couple of years ago, one of our club members came to me and asked me if I could help re'maiden their Senior Cadet. They crashed and he and his son rebuilt it. They put an OS 90 on the thing. It was way overpowered, but that's the way they wanted it.

Anyway, I flew it and it flew like a brick.. either all throttle, or it was not going to fly. But, it needed some adjustments to the CG so I told them that it did.. and they played with it. When I walked over to the thing, well, they were using wrenches over the fuel tank as nose weight... and I mean wrenches!!!

So, tools, in this case intentional, are not that far fetched.

CGr.

CGRetired,
That's why I put a smirk on my comment when I said it. I know a guy that left a screwdriver inside of the rear of the fuselage. He caught heck trying to get it to balance right.

ok, yeah, you're right. It was me!!!!

Ken

The plane is so large that it will fly fine regardless of the weight

Yup. You are so right. As for my Tiger 120, well, even with that over one pound of added nose weight, and with those wrenches in the nose of the Cadet, well, they flew. But their rebuild of that cadet was somewhat beefy.. it was indeed heavy. I recall getting it off the ground, after a rather long take-off roll, it finally went airborne.. then flying at full throttle to gain altitude. I cut the throttle to about half and it immediately started to head towards terra-firma. I slowly added throttle until it started to level off again, and slightly climb, but realized that I was at full throttle!! Jeech, what a beast!

They also had a stick looking thing, all black. It too weight in more than it was probably intended to weigh, but I flew that too. And that was even more beasty than the Cadet. I got it up alright, but like the Cadet, it too required a lot of throttle to fly, if you want to call what it did was fly.

CGr.

This is my last plane that maidened tail heavy. I really wanted to get another flight out of it, I was alone at the field, and this is what I came up with. It flew great, and when I got home, I moved the wing back 2 inches.

And I would not recommend that anyone try this at home.