So whos got a Logo20?

[50feet]

I have 20 Im working on and I could use some advice on batteries or what ever.

I have the 96 tooth version. Since these were fine before the new version do I real need to upgrade?

What's the way to go with batteries? They suggest Nicads for 3D over hydrides, or 2 x 4SEP LiPoly. Im not up to speed on lipos so Im not sure what that means.

TIA for the help.

[Robert-CSD]

Hi 50feet

I did a little calculating and with the 96 tooth main gear the Hacker motors, that are designed for that size of heli, are out of range. In order to pick the correct motor you will need to change to the new gearing. That's the 138 tooth Main gear and 10, 12 and 13T pinion.

Batteries options are like fuel. By going up the chain you get more from less overall weight. It's goes like this: Nicad, NiMh, Lipo's.

Li-po's are the thing to use, but the prices are relative.

Robert

[Ben74]

i have a logo 20. what motor are you using? i would not recommend a hacker. if you're going to use roundcells, the GP3300s are probably your best bet. after that, the HRSC2600 NiMH are good too. NiCds are obsolete. NiMH easily outperform them these days. go with at least 24 cells.

however, LiPos are always better. an 8s3p pack of gen2 thunder powers would be the best option.

[50feet]

Well Im still looking at engines but im thingking of using the mega 22453 with 1000 kv or the 22453e(energy star) with 800kv. It seem to work well in the 50 conversions like to did with his raven.

I also think I will get the bigger main gear. Im not big on mods unless it is needed

[Ben74]

the 96T main gear works fine. the only reason to get the 138T gear is if you need a higher ratio. the max on the 96T is 12:1 with a 8T pinion, and the max on the 138T gear is 13.8:1 with a 10T pinion.

the mega 22/45/3E should work well with 24 cells or 8s3p. you could spend a little more and get a tango 45-8, which is a better motor, but you could also spend the money you save on the motor on LiPos :)

[Robert-CSD]

That is a very good power set-up. I missed the 8 tooth pinion for the older gearing.
After looking at the gearing with the 8 tooth pinion the Hacker C50-18XL has the same high performance as the Tango 45-8. As a matter of fact the numbers are almost identical.
The Mega is also a good choice with the efficiency at 83%. I have not used this motor but it is something I will have to try.
Where is the thread one the person you mention using this motor for his heli?

[50feet]

Tom fiddler has a video of his electric converted Raven using the 1000 kv mega

http://www.rcgroups.com/forums/showthread.php?t=214956&highlight=raven

Here are many others who have done the same and the all use the Mega. Since the converted helis are 2 or 3 pounds heavier than the Logo I figure it will work well in a logo

[Ben74]

a tango will have much more torque than a hacker at the same rpm. a stock logo 20 cannot get the gearing deep enough to truly take advantage of a hacker. you would need a two stage reduction with a ratio of around 20:1, like the ion.

[Robert-CSD]

I saw that when I was checking out the ION. The big 90 is using the same motors as the Logo 14 and 20's. Also, when I was checking out the Raven thread. The two stage gearing is nice. Seems that is the way to go... :D