Originally Posted by ajbaker
If you use a CG of 72mm, you can use a 1300mah 3S1P lipo easily with no extra ballast. While the suggested CG is 60mm, I can assure you that 72mm is just as stable. If you added things like a cf 3mm tube down the antenna slot or added a CF tube on the stab, it might be impossible. I have two planes that I set at 72mm and use a 1300mah lipo and they fly perfectly. When I set the CG at 90mm, it becomes very aerobatic and really fun to fly (for me) - Yes. It does take a bit more experience to maintain stability at that CG setting. I don't consider that excessive since it is still very flyable. It is fair to say that an excessively nose heavy plane will not fly either.
Just an observation from the sidelines here but....
I'd read & taken note of the various CG's mentioned whilst I's building & modding my Bix (even before, in fact)....and had not REALLy 'applied' the info or let it 'sink in' as to what it signified. Until I got to the stage where I marked different colored dots along the measuring points at 60, '62' and 70mm. I say '62' as, it would've been so close to the 60 it would've only served to make the 60 look fat. So I placed a dot at 65....sort've an 'in between' point.
And my point here is....when you have some actual points to LOOK at and consider, there aint very much open range between 60 & 70mm
!! It's only 1cm difference!
Considerably less than the previously prescribed 'fingertip' balancing method's very 'tool'
- the fintertip! (OK, maybe I've got fat fingers....not an original postulation, I assure you - proven many times over my life!! *LOL*) But heck - you can barely get the professional tool new pencil eraser in there with any room to spare!!
What I'm suggesting is, I don't see how 60 or 70 could be much more than 'a suggested inclusive area'....and seriously doubt 99% of our fliers are placing their LiPo packs anywhere more precisely
to hit either of those figures exactly, much less anything in between, than AS a generalized spot. And hence, fussing over THE exact spot ain't as deserving as we've made it. 2mm as a point of contention?? C'MON!!!!
By all means please correct me if I'm wrong. But first, mark 2 dots 1-cm apart, and assure me when those spots are covered in velcro, you can place another velcro covered object thru a smallish opening & locate precisely on either point.
Thoughts -- or confessions?