CG question

Well in that case my Ringmaster is very nose heavy.

How in the world do I add tail weight on a profile and not make it ugly. Thanks for the explaination Wilf.

Ron

I would have the wing on,, and then straight down the wing Ron. Measure back from your leading edge of course as per the plans.

I have a set of the Great planes balancing sticks which has clear rulers on it, and that setup puts the balancing points on the wing, close to the fuse. Those balancing sticks are adjustable, spreadable. so you can put the points right in tight to the fuse,,but on the wing itself. (Little rubber footed pads that pivot on a ball joint)

PV Pilot wrote:I would have the wing on,, and then straight down the wing Ron. Measure back from your leading edge of course as per the plans.

I have a set of the Great planes balancing sticks which has clear rulers on it, and that setup puts the balancing points on the wing, close to the fuse. Those balancing sticks are adjustable, spreadable. so you can put the points right in tight to the fuse,,but on the wing itself. (Little rubber footed pads that pivot on a ball joint)

Well isn't that cool. Much better than my straight pins resting on two bricks.

PV Pilot wrote:I would have the wing on,, and then straight down the wing Ron. Measure back from your leading edge of course as per the plans.

I have a set of the Great planes balancing sticks which has clear rulers on it, and that setup puts the balancing points on the wing, close to the fuse. Those balancing sticks are adjustable, spreadable. so you can put the points right in tight to the fuse,,but on the wing itself. (Little rubber footed pads that pivot on a ball joint)

Or, you can use a REALLY sophisticated balancing jig like mine!



Does the job!

That looks like one I can afford!

"How in the world do I add tail weight on a profile and not make it ugly"

I used to bore a quarter sized hole completly through the profile fuselage as far aft as possible and glue clear plastice on each side leaving a cavity. Small hole on one side near top of circle to add BBs one at a time until balanced.

Remove BBs through drilled hole out the bottom of the fuselage

I use the 1/4 oz lead stick on squares. I peel the sticky off and smash them with a hammer. They become paper thin. You can use a hinge slotter and insert the weight right in. You can also put brass dubro wheel collars on the pushrod at the rear soldering them on. Using light foam r/c park flyer wheels up front is the easiest way to shift the cg to the rear. You can also buy bullet slider sinkers and they stack on each other. Drilling a hole into the end grain of the fuse you can insert quite a bit. Ken

Ken Cook wrote: I use the 1/4 oz lead stick on squares. I peel the sticky off and smash them with a hammer. They become paper thin. You can use a hinge slotter and insert the weight right in. You can also put brass dubro wheel collars on the pushrod at the rear soldering them on. Using light foam r/c park flyer wheels up front is the easiest way to shift the cg to the rear. You can also buy bullet slider sinkers and they stack on each other. Drilling a hole into the end grain of the fuse you can insert quite a bit. Ken

Ken,

Your a wealth of knowledge. Thank you kindly! Very good suggestions.

Ron

fredvon4 wrote:"How in the world do I add tail weight on a profile and not make it ugly"

I used to bore a quarter sized hole completly through the profile fuselage as far aft as possible and glue clear plastice on each side leaving a cavity. Small hole on one side near top of circle to add BBs one at a time until balanced.

Remove BBs through drilled hole out the bottom of the fuselage

Hey Fred! Where ya been?

Thanks! Also a very good suggestion. BTW that Pee Wee you sold me is about to go to work on a Queen Bee!.

Ron

Lurking for a while...retired life is more arduous than I imagined

fredvon4 wrote:
Lurking for a while...retired life is more arduous than I imagined

Have you discovered what a lot of us already know? like how did we ever find time for work?

Ivanhoe wrote:Or, you can use a REALLY sophisticated balancing jig like mine!



Does the job!

Nice Honker!

George

On a high wing the fulcrum should be below the wing, mid wing or low
Wing fulcrum should be from above ie dangled.
If nose heavy thank the stars it's easier to remedy than tail
Heavy.
I'm sure ultimately c/l is the same as r/c so once up, fly inverted
At full throttle and climb at 45 degrees and watch what model does....
If it climbs above 45 degrees it's tail heavy. If it falls away (to earth)
From 45 it's nose heavy. If it continues at 45 for more than a
Few seconds it's spot on.
Once the c of g is sorted all the rest falls into place.
Good luck

John Goddard wrote:On a high wing the fulcrum should be below the wing, mid wing or low
Wing fulcrum should be from above ie dangled.
If nose heavy thank the stars it's easier to remedy than tail
Heavy.
I'm sure ultimately c/l is the same as r/c so once up, fly inverted
At full throttle and climb at 45 degrees and watch what model does....
If it climbs above 45 degrees it's tail heavy. If it falls away (to earth)
From 45 it's nose heavy. If it continues at 45 for more than a
Few seconds it's spot on.
Once the c of g is sorted all the rest falls into place.
Good luck

One small problem John, I have to learn how to fly inverted first!

Lol,. Or just flip the low wing plane over and set it on the balance sticks for a baseline balance.

PV Pilot wrote:Lol,. Or just flip the low wing plane over and set it on the balance sticks for a baseline balance.

That's what I do!

cribbs74 wrote:

John Goddard wrote:On a high wing the fulcrum should be below the wing, mid wing or low
Wing fulcrum should be from above ie dangled.
If nose heavy thank the stars it's easier to remedy than tail
Heavy.
I'm sure ultimately c/l is the same as r/c so once up, fly inverted
At full throttle and climb at 45 degrees and watch what model does....
If it climbs above 45 degrees it's tail heavy. If it falls away (to earth)
From 45 it's nose heavy. If it continues at 45 for more than a
Few seconds it's spot on.
Once the c of g is sorted all the rest falls into place.
Good luck

One small problem John, I have to learn how to fly inverted first!

With a C/L model the CG is nowhere near as critical as it is in R/C or F/F.
Basically, slightly nose-heavy is acceptable, although the control response will be more sluggish, TAIL heavy is a no-no, if it's way out the model will be unflyable, or at the very best so sensitive as to be impossible to fly successfully.
Excessively nose heavy would mean you having to keep full up elevator on to get it to even wallow around the circle, or plowing in three feet in front of the launcher!
Add weight to the tail until the CG is somewhere near the correct place, but there is no need to be hyper-critical if it it slightly in front of the correct balance, just don't get it behind!

Wilf