Balance Stands

[WMcNabb]

Since a picture is worth a thousand words, I've attached the full scale Pitts Model 12 example from the Jim Kimball Enterprises website.

 

[Mark Harper]

This is from the IMAC Technical Reference Area.

Now thats a lot easier to follow.

 

[stangflyer]

I just been using my fingers. There is such a wide range of CG on these planes, get her close, fly, move batteries around till you get her where you like.

I just really can't use my finger tips. Ya see, it's like..well umm, well it is sorta like....my arms just do not reach from one side of a 122 inch wingspan to the other.

 

[jhelber08]

I just really can't use my finger tips. Ya see, it's like..well umm, well it is sorta like....my arms just do not reach from one side of a 122 inch wingspan to the other.

Thats why I'm married......she hates it though when its time to check the cg on a plane. Okay...that's not the only reason I'm married

 

[ChickenBalls]

I just really can't use my finger tips. Ya see, it's like..well umm, well it is sorta like....my arms just do not reach from one side of a 122 inch wingspan to the other.

That is a "GOOD" problem to have, and a very good point. I think my KISS method of fingers, works, up to a point. SO my wife was lying to me all this time, and SIZE does actually matter. ANYwho there are some balancers out there, and I like your homebuilt one a lot, simply because the others are pricey. I have never tried it, but the Vanessa? method of hanging the plane, may be a cheap easy balance option.

 

[stangflyer]

Thats why I'm married......she hates it though when its time to check the cg on a plane. Okay...that's not the only reason I'm married

It's cuz she lets you buy things and she makes ya dinner and she washes your clothes....wait a minute...yer all making me want one again. LOL

That is a "GOOD" problem to have, and a very good point. I think my KISS method of fingers, works, up to a point. SO my wife was lying to me all this time, and SIZE does actually matter. ANYwho there are some balancers out there, and I like your homebuilt one a lot, simply because the others are pricey. I have never tried it, but the Vanessa? method of hanging the plane, may be a cheap easy balance option.

Was she really lying to you? She'll never tell you. LOL..... I have not seen the method of hanging to balance. Please share.

 

[jhelber08]

It's cuz she lets you buy things and she makes ya dinner and she washes your clothes....wait a minute...yer all making me want one again. LOL

I work offshore...At work we put our clothes in a bag, stick them outside our room and they magically appear washed and folded the next morning...I tried that at home and got a black eye and now I have to do my own laundry. Honestly though I can't complain, I got a good one! Now if I could teach her to iron covering....hmmmmm

On a serious note though, alot of times the cg range given will line up with the wing tube. In that case or when my wife isn't around I just tie a little string around the wing tube, slide the wings on and move my batteries around until it picks up pretty level. Its close enough for a maiden and then after that I'll move the batteries around until I like it.

 

[stangflyer]

I work offshore...At work we put our clothes in a bag, stick them outside our room and they magically appear washed and folded the next morning...I tried that at home and got a black eye and now I have to do my own laundry. Honestly though I can't complain, I got a good one! Now if I could teach her to iron covering....hmmmmm

On a serious note though, alot of times the cg range given will line up with the wing tube. In that case or when my wife isn't around I just tie a little string around the wing tube, slide the wings on and move my batteries around until it picks up pretty level. Its close enough for a maiden and then after that I'll move the batteries around until I like it.

I hear what you're saying, but I had a friend one time that did the hanging from the wing tube trick.... So grosely tail heavy that the plane went up... snapped, stalled, drilled itself into four hundred feet of paved runway. Since that time I have been quite anal about being more accurate.

 

[jhelber08]

I verify that the wing tube will work. For instance, if the manual gives a 5-6" cg range from the leading edge at the wing tips I'll measure and mark those two spots on each wing and then stretch a tight string from tip to tip to see where it ends up on the fuse. If its above the wing tube, then I'll hang it from the wing tube to check. Otherwise, I use my wife to hold the wing tip. I'll move my batteries as far fwd as possible to hit the front CG mark and then move them back as far as possible until it balances around the aft cg spot. Then from there I know a pretty good range of where I can put my batteries and rx equipment and usually shoot for somewhere in the middle where the batteries are easy to mount and adjust as needed. All of my planes have come out slightly nose heavy with this method which is where I tend to keep it. The only plane I have that is completely neutral is my 88 ef edge in which it gave a cg range slightly behind the wing tube which lined up with the fwd wing bolt. I hung the plane from the wingbolt and mounted my batteries accordingly.

I tried using one of those stands before on a 30cc bird and I about pulled my hair out which there wasn't much left to start with. After that I just focused on getting it within the suggested range and then fine tuning it after flying.

 

[ChickenBalls]

It's cuz she lets you buy things and she makes ya dinner and she washes your clothes....wait a minute...yer all making me want one again. LOL

Was she really lying to you? She'll never tell you. LOL..... I have not seen the method of hanging to balance. Please share.

Rob here is one example

I have never seen it done like this, but have seen it hung by the wing tube, and using a plumb bob. Here is more of the one I seen. http://www.rcuniverse.com/forum/tips-techniques-180/708060-vanessa-c-g-rig-how.html
There are a few more examples out there, but I don't promote or provide links to azzhat's site.

This one kinda neat also