center of gravity adjustments

[istandalone]

after trying several times to get my COG fixed when running 8 cell a123, i found out that my canopy doesn't fit with the way i have to have the cells. what are my options for adding weight to the tail? i've already got the boom mount tail servo, so that's out. the other issue is that this will need to be removeable, being that the rest of my cells balance easily. would adding a metal weight clipped to one of the stabilizer fins be kosher? i assume that because the vert fin is so far back, it won't take much weight to do it. any ideas?

[mjdee14]

I saw one other post that someone had used some big washers and a bolt on the vert tail fin. it was removable when needed or he could take of or add washers as needed.

there really aren't too many options.

[Mikej]

Someone (either here or RCG) had bolted a heavy looking nut and bolt to their vertical fin - not very subtle, but probably effective

Whoops - same as what mjdee said :)

[Madedon]

after trying several times to get my COG fixed when running 8 cell a123, i found out that my canopy doesn't fit with the way i have to have the cells. what are my options for adding weight to the tail? i've already got the boom mount tail servo, so that's out. the other issue is that this will need to be removeable, being that the rest of my cells balance easily. would adding a metal weight clipped to one of the stabilizer fins be kosher? i assume that because the vert fin is so far back, it won't take much weight to do it. any ideas?
Hi istandalone
Here is a few pic of my old set up, when having the plastic frame.
http://www.helifreak.com/showthread.php?t=37258&page=5
It was quite robust but be carefull the hard landings, you can end up bending your tail boom every time you have a hard landing. CF frame :Bangsolve all this....

[concept1]

thats the reason I went with the Rotorworks frame. so far I have had great luck with perfect balance with any cells. adding extra weight is never the best idea.

[Madedon]

That's the one I got and it works like champ, espesially with heavy batteries.

[istandalone]

the only reason i'm hesitant to buy a cf frame kit, is one thing the $, and two are there any kits that are "all inclusive" meaning come with everything you need? it seems every cf frame upgrade out there you need to buy servo mounts, bearing blocks, gyro mount ect. if i can find one package that has everything i need, then i'll think about it.

madedon- how does your canopy fit like that? did you need to remove the bottom canopy support to get it on?

[Madedon]

It's a bit tight but the canopy fits fine without any modifications. The CF frame I m using is this one and it came with everything I needed (servo mounts, bearing blocks, gyro mount ect) except the bearings that I had to take out from the plastic frame.
This work out for me fine, as I did a complete build of the Heli and found some problems I had with vibrations and the tail fluctuation thing/problem which ends up to be a few defective berings, the tail pulley and beld.

[Madedon]

The CF frame I m using is this one:

SORRY forgot the link http://rotorworkz.com/html/fcs.html

[vicrc]

Before I went with a carbon frame I ended up cutting the plastic frame in front of the servos. I also moved the ESC to the side frame. I then mounted an aluminum plate to hold the batteries. It was much easier to CG and easier to put the canopy back on. I know its a terrible hack! But then again maybe it should have been designed that way.

[Jungle Bob]

I have a range of batteries (varying sizes and weights) for my Hurri and regularily use trim to accomodate the imbalance, just an idea.

[vicrc]

I have a range of batteries (varying sizes and weights) for my Hurri and regularily use trim to accomodate the imbalance, just an idea.

This is the main reason I hacked the frame. To hard to cg and if its not close trim trim trim, by the time its all good and steady, 1 less minute of flight.

[istandalone]

i acutally borrowed madedon's idea. ended up putting a bolt/nut and a few washers in the top of the vertical tail fin. this balances the 8 a123's perfect, and with the evo30's i have enough room to move them back to balance it, no nuts/washers needed. the only issue is that with 8 cell a123 i can't fit my canopy on, well, it goes on but it's a stretch. for this reason i might end up going just 7 cell a123, 4 cell pack on top and 3 cell pack on the bottom.