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Jim Condor
05-29-2006, 07:30 PM
I have just recieved and put together my Spectra Select
and I have noticed how heavy the Nicad battery and motor
system are on this beautiful sailplane. I am a beginner and
I was wondering if I should switch to a brushless lipo set up?

Any suggestions?

Thanks,

Jim

Sky Sharkster
05-31-2006, 01:44 AM
Hi Jim, welcome to Wattflyer! The short answer to your question is "not necessarily". The typical "Speed 600" (or 550) can motors that come with 2 meter gliders aren't powerhouses by any stretch, but they will get the model up to thermal altitude. It won't be fast, maybe a minute or more of motor run, but you'll get 2 or 3 such climbs out of each battery charge. Add in the normal glide time from 400 feet of altitude and maybe a thermal, and a flight will be 15 minutes plus.
There are a few things you can do to get better performance out of the stock motor: A water break-in will help with motor life, and an 8 cell NiMH battery will weigh about the same as the 7 cell NiCad and deliver more power. I believe the model comes with a "sport" 8" x 4" folding prop; Swap it for the same size "CAM" folder from Hobby Lobby.com and you'll see a real improvement in the climb.
If the battery connectors are the white plastic "Tamaya" type, trade them for Deans Ultra's. Much better performance, reliability, and they don't lose power with each un-hooking cycle.
And if all of that doesn't work to your satisfaction, my recommendation is the AXI 2808/16 Outrunner, 9" or 10" x 6" CAM folder and 3 cell 2100mAH LiPo! Bear in mind you will need a brushless ESC, LiPo charger and a bit of work on the nose to adapt it for an outrunner.
Perhaps you could try flying the model "stock" and see how you like it. You can always retro-fit the brushless/LiPo later.
Good Luck! Catch a thermal!
Ron

pilotpete2
06-03-2006, 10:59 PM
Jim,

I had a Specra ARF a while back, I went brushless with a Multiplex geared 4.4:1 4 turn motor, since it's a planetary gearbox it will fit in very tight fuselages, it'll be lost in the Spectra, no nose job necessary:D, put a 3S lipo with a 11X8 Aeronuat Cam and hang on:)

Pete

AEAJR
06-10-2006, 02:27 AM
My Friend has a Spectra Select. Flies it on the stock set-up with 7 Cell 2100 mah NICD. Flies fine, but not super powerful. However he enjoys it just as it is. I have flown it and it is fine.

You can go Lipo first. That will probably drop 6-8 ounces in weight which will make a big difference. He once flew it on my 2 cell 2100 mah Lithium pack. Instead of 13 ounces, it weighs 4. Less voltage but a LOT LESS WEIGHT. If you go 3 cell Lithium you may have to reduce prop. At the higher voltage it will eventually burn up the brushes, but then you can switch to brushless if you like.

Best set-up for that brushed motor would be 8 A cell NiMh pack of about 2000-2500 mah. Probably 1/3 less weight with more duration. Perhaps the CBP2500A on this page:
http://www.cheapbatterypacks.com/main.asp?sid=570803&pgid=custompack
They will make up a custom pack for you.

Or you can go 8 cell 3800 Nimh Sub C. Same weight, more power and twice the duration. If you go brushless later, the pack will work fine but you will get more power and duration again.
Perhaps the IB3800
http://www.cheapbatterypacks.com/main.asp?sid=570803&pgid=custompack


Here is a thread on some issues on the Spectra Select that may or may not effect you but good for you to know about.

Spectra Select & e-Aspire - RTF problems
http://www.wattflyer.com/forums/showthread.php?t=593 (http://www.wattflyer.com/forums/showthread.php?t=593)

dhable
06-15-2006, 09:34 PM
I swapped out the stock motor in my spectra for a Jeti Phasor 30/3 from Hobby Lobby. With a 10 cell ni-cd pack, it climbs to thermal altitude in under 20 seconds. Next, I'll swap out the heavy ni-cd for li-po's and lose a lot of weight. I love the plane!