Cheap AA cells for soaring

[rlt55]

I've been wanting to make a cheap Rx nicad pack the will last a few hours.

I think that AA sized 1000 mAh nicads might do the trick.
I just ordered a couple sets from Zbattery.com
They are $6.97 for 4 ($1.67 each). I will make my own packs or buy a 4-AA battery holder.

Comments?

Rich<>

[DryFly]

I suppose my 2 cents would have to be based on what was being flown and how tight your margin is weight wise. In all of my larger birds (standard and up) I just wire in a radio shack holder and don't really bother with making up packs unless it is a really narrow nose and I want it as far fore as possible and have to create a bizzare shape. The wieght gain when using a holder is minimal and not even a thought when flying the craft I do (big RES floaters). Especially when the wind is up and Im planning on dumping in a bunch of ballast anyway. Sure made up packs are sexier but I just don't take off the hatch cover when anybody is looking :)

[Spam]

It depends on what capacity you really need: check the for sale forum: Somebody's selling AAA NiMh cells for .61 ea... Now that's cheap...

[rlt55]

RadioShack just may be the way to go.
I use AAAA NiMh cells on my lightweight stuff,
but my Supersmart charger really likes Nicads.
(It does them in Auto mode really fast).
Rich<>

[Tony Oliver]

Almost all gliders - and in particular, scale gliders, have noseweight. All I do is replace the noseweight with an appropriate size and weight of NiCd or NiMH batteries. Apart from often lowering the overall weight of the model, you can fly until the tx runs down.
Tony

[Ric Duley]

I've been using 720 ma AAA NiMH cells in my HLG and they've worked great. They're lighter than nicads, last forever and replaced the lead formally required in the nose.
I'll be adding them to my larger sailplanes next.

[Tony Oliver]

A flying pal commented that if you replace ballast with batteries, the overall weight doesn't alter. He hasn't got the point so I thought I'd clarify it for anyone else who's puzzled.
If you take out the lead, the battery weighing more than the older one can be moved a lot more forward thereby increasing the effect of the weight. ie length of battery + lead has the effect of distributing the weight along the nose - putting it in the extreme nose can make a difference. How much depends on the model.
Another thing, if I have , say 2000mah batteries in the model, and fly until the tx is dying, how much extra battery weight is needed in the tx to match? Will I want to carry this around for hours, should I take a packed meal etc.. Should I forget this and go in for flower pressing or stamp collecting...........

Tony

[oldpilot]

Tony. In my standard Slopers, you know, like the CS, DAW, MMGlidertech, MAD etc:, I make up 4.8V packs from standard 700mah Sanyo AA size batteries. I solder them up into a square block, and bury them permanently in the nose as far forward as I dare.
I charge them via a servo lead plug wired into the RX switch so that when the switch is OFF, I can charge the batt. When its on, the Batt. feeds the RX. Simple and needs no maintainence. You have to check everthing is secure and works properly before you bury all the gubbins in the fuse, 'cos you don't have a second chance if anything goes wrong, and the the only recourse is "Keyhole Surgery." But i've had no problems so far(touch wood).
In my blue Spitfire I didn't shove the battery far enough forward and had to put 4oz of lead behind the spinner. However I learnt my lesson on that one and have never had to use so much lead again.
In fact, on the F-20 Tigershark I put the battery,RX, LMA switch and charging plug, plus a laminated ply insert for the VOOOOM!! launching hook all forward of the LE and as a result needed no lead in the nose at all.

Cheers. Patrick.:cool: :) :D

[Tony Oliver]

Patrick - my sentiments and methods are entirely the same. There's no use in dead weight in a model - use the space and weight allowance to have more facilities - extended battery power, toys such as lights etc, lost model alarm, battery checker (all things you buy as insurance but never need again).
In windy weather, there's only one place for ballast and that's on the CG, or in tubes in the wing close to the CG.
Happy flying - keep the number of landings equal to the number of takeoffs/launches.

Tony