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Old Oct 15, 2001, 02:01 PM
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United States, MI, Holland
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Good batteries for GWS-A Drive

I am looking for better performance for my little fun-fly plane. It's a GWS-A drive with an APC 10x4.7 SF prop.

I have been flying it with a 7-280NiMh pack from Racical RC and it works, but I want more power. I was thinking of going to 8 cells and using NiCd s like the 100 or 150 size.

Any ideas on light NiCd with decent capacity that will give 5 minute flights on a GWS-A drive?
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Old Oct 15, 2001, 04:15 PM
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United States, OH, Dublin
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I have been using the 7 cell 300mah nimh batteries and a 9x7 prop on the light stick and it seems to have plenty of power.
R/C Planes and Stuff!!

-Keith
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Old Oct 15, 2001, 04:29 PM
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Walled Lake, MI, USA
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I guess it all depends on how often you want to replace the motor. More cells = shorter motor life. A few people have gotten away with 8 cells with careful throttle modulation. Most have smoked the motor in a few hours or less, based on messages posted here. GWS recommends the 9x7 prop for outdoor flying and the 10x4.7 for indoor flying. Many have found the 9x7 GWS prop to be fragile. I broke several and switched to an APC 9x6. It performs well and doesn't break.
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Old Oct 15, 2001, 11:27 PM
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other batts

Try the 370 NiMh that fyersrus(http://www.rcgroups.com/forums/showt...threadid=12432 ) is selling in the classifieds. Same size as your 280s. I have an 8x300 NiMH pack from RadicalRC that works great, plenty of power and long flight times. I have been thinking about ordering some 370s but may wait 'til spring at this point. Perhaps the capacity will go up some more by then. I have had a couple of 280 packs that have not had much power. The 300s are much better. I also think the poor 280 packs may have been a function of my very inaccurate Astro 110D. I have since purchased a Simprop Intellicharger (like the FMA smart charger). Much better charging.

Joe
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Old Oct 16, 2001, 09:46 AM
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I'm hesitant to recommend my 1st choice because it seems lots of people don't have sucess with them. I have 10 of the Rayovac 9volt (8.4 really) nimh batteries. They look like traditional 9volt rectangular batteries. They have 150mah capacity and give me 5-6 minute flights. Their weight is only 1.5ounces. They can be sensitive to charging so if you try them be sure to read up on them first.

I also have the 6 cell nicad 270 packs and am not too fond of them. They weigh 2.7 ounces and only yield about 5-6 minute flights since I have to run pretty much full throttle with them. Other choices I've read about are the 720mah AAA nimh batteries. Heavier but much longer run times. Finally I just bought my first li-ion battery pack. It is rated at a whopping 1350mah, 7.2volts and 3.2 ounces. Haven't actually flown with it yet but looks promising.
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Old Oct 16, 2001, 10:36 AM
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Rochester, NY, USA
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MT,

I'm not sure what your definition of "better performance" is but my interpretation of your meaning is that you want more thrust.

In general, you should always use NiMH or Lithium cells for DX series motors. NiCds cells at 1-1.5amp draw provide no advantage.

Your 7-cell 270mAh pack will benifit greatly by adding an 8th cell. My favorite pack for the DX-A motor is the 8-cell 300mAh NiMH pack from Radical RC.

I have 75 flights on my Pico Stick, 30 flights on my Tilde wing, and 15 flights on my super-Cannonshot. All 3 planes use the DX-A motor with the 8-cell 300mAh pack.

Good luck!
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Old Oct 16, 2001, 12:37 PM
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Walled Lake, MI, USA
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I should have said in my first message that those using 8-cell NiCd packs generally seem to have more problems smoking motors. Those using 8-cell NiMH packs seem to have fewer problems. But a few people have reported early GWS IP motor failures even on 7 cells, which could be related to some motors not being up to spec due to production variables. I decided to be ultra-conservative and have been flying with a 6-cell AAA 700mAh NiMH pack (7.2V). This pack will run at full-throttle for 35 minutes or more while barely making the motor warm, and the TM will still do a loop from a dive after 30 minutes of flight. I'm awaiting delivery of a bunch of 2-cell 830mAh Li-ion packs (7.2V), which are 3/4 oz. lighter than my current pack. If you can get the performance you want out of 7.2V, which is the recommended maximum voltage for the GWS IP motor, there's no reason to use more voltage and overstress the motor.
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Old Oct 16, 2001, 12:44 PM
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I have to agree with Greg.
"Your 7-cell 270mAh pack will benifit greatly by adding an 8th cell. My favorite pack for the DX-A motor is the 8-cell 300mAh NiMH pack from Radical RC."
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Old Oct 16, 2001, 01:00 PM
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Dave, I'm really interested in those 830mah li-ion packs. Be sure to let me know how they work out. I think Greg C bought some too. Greg, can you give us a report on the lithium cells? How they working out? At 2 ounces, sounds great to me.
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Old Oct 16, 2001, 01:10 PM
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I didn't get a chance to try them out last weekend, Matt. I brought only larger planes with landing gear and forgot about my Lithium cell testing.

With the wife traveling until next week, you know I'm gonna be out flying all this weekend.

I'll give them a try a let you know. I bought both the 830mAh and 1100mAh Lithium Ion cells.
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Old Oct 16, 2001, 03:31 PM
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Since I could get 10 packs and a charger for $34 shipped, I'm tempted to go ahead and order but will wait until you or Dave gets a chance to at least bench test yours to see if they really work.
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Old Oct 16, 2001, 08:14 PM
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The only thing I test on my workbench is my building ability. All of my aircraft testing is done in the air. So I won't be able to supply any bench testing results of the 830mAh packs. But I will be able to compare their flying performance with the Tiger Moth against my current 6-cell AAA NiMH packs. With a little luck in the shipping and weather departments, I may be able to get in the air this weekend.
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Old Oct 17, 2001, 12:52 AM
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Laguna, CA
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I've been eyeing the Li Ion packs and tried some of the non-chargable one to mediocre success. I'll be interested to hear how they work for you.
Where are you guys getting the 830mAh and 1100mAh Lithium Ion cells, and how are you charging them?
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Old Oct 17, 2001, 07:40 AM
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Walled Lake, MI, USA
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All of your questions and more are answered in the following thread:

http://www.rcgroups.com/forums/showt...threadid=10622
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