Goirish I do know what you are talking about and that is caused by the rounded airfoil shape on the top side of the wing which does not allow the measuring device to stick straight out in front of the leading edge when resting on the pads. It is a varible that will occur among a variety of airplanes.

The Great Planes balancer corrects for this by allowing the rules to pivot at the pad getting the stops in front of the leading edge. The Sig balancer will not do this due to the design of the slides and pad.

What I would do and have done with a few low wing airplanes is not ballance upside down but uprite instead. Yes it will be less stable that way but manny low wings can be balanced with care an in many cases allowing rules to be in a better position due to a slightly less curved surface on the bottom of many airfoils.

All the balancers and balance methods do have a variety of problems with no perfect one size fits all. I do use both the GP and Sig balancers along with just my fingers. Thats a favorite of mine on my controlline stuff since on those the symetric airfoils with the desired CG so far forward that they don,t balance well on any table top balancer because of the problem you experianced. For those I always simply make my decison as to where I want the CG, measure it on the table and drop a dap of epoxy on the wings at that point making checking the balance instant on your finger tips.

For larger stuff the popular hanging methods and one called sometimes the vanessa are useful but those are difficult for me setting up in my wheelchair so usually for my largest stuff around 26 pounds I usually just have two wing walkers sit the airplane in my fingers in my wheelchair and its easy to find the CG.

Actually hardly a day goes by without someone walking up and sitting an airplane on my fingers and wanting an opinion. Its surprizing how quickly you will learn to estimate Mac and developing ideas on what percentages of that Mac to use for many kinds of airplanes and no computers needed.

I hope that maybe that will help you to enjoy your new tool a little more.


John