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Old Dec 29, 2003, 02:15 PM
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Stock Projeti Lipos?

Got the reno edition and built it completely stock and I'm using 8 500Mah Nicads. I really like the way it flys, launches etc however, with these small packs flight time is only about 3-4 mins. What Lipo pack would give 10-15 min. duation and not add a lot of weight. Really like this little wing, it kinda reminds me of James Bond's microjet, and the slow speed manuverability is great. I don't want to overload the airframe and make it a brick to launch.

Thanks.
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Old Dec 29, 2003, 04:11 PM
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Rich,

I've been using the Kokam 3 cell 1500 mah lipo on my Original Edition Projeti. Works great with the 400 motor. Some claim that the 11.1 Volts is too much for the 6 Volt Motor, which is probably true. I've only flown mine about 20 times with the Lip, and it's been fine. Motor's a little warm after a normal flight, but not too hot with throttle management.

I'm upgrading to a Speed 480 7.2V (one of the Viper Twin motors from JetSet) if the guy that runs that place ever ships it to me. Been waiting for 3 weeks. I don't think that the 11.1 V Kokam will burn that out, and it will give me a speed boost.

I got my first set of Kokams from Aeromicro.com for about $50, but I think he's out of stock. Then I got some store wrapped 3 cell Kokams from www.edogfight.com for $44 and they work great, but you have to add your own Deans plug (or whatever plug you're using) and these batteries have shorter wires.

BTW, if you want to consider night flying, I put E.L. Glow Wire on my Projeti, and it completely rocks!!!!!

Happy Flying

Todd Sheridan
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Old Dec 29, 2003, 04:23 PM
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go with thunderpower 2100's

The kokam's will work, but the TP's will make a little more power and keep you in the air longer. Also, the TP's are shaped better for the Projeti. As for weight, no worries. I would go with the 3 cell li-poli's too. You should get at least 20 flights per speed 400 motor, but what a ride!
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Old Dec 29, 2003, 04:32 PM
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Not sure about Thunder Power because I haven't used them, but they should do the trick. When comparing the two products I decided to go with the Kokams only because they were cheaper and they have a higher C rating (8C versus the 6C of the TP), which makes them about equal in their amp output.

And the Kokams came with a deans connector installed, which I use in all my planes.

I hated the Etec 1200s. Anything less than a 3 cell 1500 isn't good enough IMO. I'm gonna order one TP just to try it out. Can't have enough batteries!!!!

Todd
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Old Dec 29, 2003, 04:43 PM
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Oh, one more thing. The Kokams fit fine in the Projeti. On one of my hard landings, I had the battery slip out through the canopy, so I decided to start putting a strip of tape from the outer edge of the fuselage, over the top of the battery, and onto the other side of the fuselage. I layed down a strip of tape on each outer edge of the fuselage FIRST, and then taped the top strip onto that. That way I could change out the tape without ripping off foam every time I did it. Doing that holds it in snug with no worries.

But the Thunder Power, being longer, really would be a better fit if you didn't care about spending $80 per battery. I can get two 3 cell Kokams from edogfight at $44 each for just a little more than the price of a single 3 cell thunder power.

I'd be curious what the cheapest price is on a 3 cell Thunder Power from someone who buys them.
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Old Dec 29, 2003, 06:45 PM
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Thanks For The Lipo Info

The 1500 3 cell sounds like the ticket for the stock 400 set-up. I don't really care if I burn a few S-400 motors, I probably have at least 15 I have never used yet. I have a 3 turn BL system I could dop in, but all I have is the CP NiCads and that would make it heavier than I wanted. With those little Hitec HS 55 servo's and tiny linkages the stress would probably push them to failure. I wanted this plane for a nice light little ship for the local park, and it's filling the bill nicely.
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Old Dec 29, 2003, 08:36 PM
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Did u guys test the amp draw on a 6v sp400 on 3s b4? I think maybe be overdrawing & killing the lipos. 7.2v or a sp480 wud be much better.
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Old Dec 29, 2003, 09:48 PM
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Yeah, the 6 Volt Speed 400 is not the best motor to use with a 3 cell lipo, but the motor only draws 4 amps under normal load, though Graupner claims that it can draw up to 25 amps under heavy load (stall loads), but I seriously doubt that ever occurs on a direct drive prop this small. Maybe it would draw that much if it were driving a large prop on a large plane with a low ratio gear box.

But I've run this Projeti all-out at full speed for an entire flight, and the battery barely got warm. (The motor was practically smoking, but we're not talking about the health of the motor! )

A 7.2 Volt 400 or 480 would be a better motor, which is why I'm upgrading to that. I've read the forums with guys that are putting brushless motors on this plane, and the thing literally rips itself apart pulling out of high speed dives. That's just silly. The plane is already extremely fast.

You're better off putting money into a night flying kit, IMO.

I just posted an image with my glowing Projeti in a new thread.

http://www.rcgroups.com/forums/showt...hreadid=183457

Todd
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Old Dec 29, 2003, 09:59 PM
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Projeti Motors

Thanks for the Projeti motor info update, I have a couple of the black can 400's coming this week. I'm gonna run 10 500Mah AR cells until I get the Lipo's. Should be a good warm up in performance without all the weight. Thus far this is my favorite wing, it has a nice finished appearance, very portable and does all the tricks. I've seen the BL set-ups fly as well, last 2 tore the motor off the keel of the plane.
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Old Dec 30, 2003, 01:25 AM
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TP's....price and amp output capabilities defined.

As far as price...I bought my TP's at the LHS for $62.50 (3s1p 2100's). Now, for amp output capabilties....that depends. I decided that I would treat my first pack as though it were indestructable, you know...just to see...Using an astro ampmeter, static testing in a flat-foam 3D plane/uberall-Nippy 1812-100 and 10/6 prop. They managed 21 amps X 20 seconds with no noticable heat generated, but a noticable drop in voltage and power output..(the amps dropped considerably of course) However, with 2-3 seconds recovery output was as before. I cycled as such about 7 or 8 times, with barely noticable warming of the pack. I have flown this combo for at least 60 cycles of charge and discharge, during pretty intense 3D flying with no appearant performance loss. So, in my opinion, it's probably safe to discharge( for short periods) at considerably higher rates than advertised. Remember, 8C is for continuous discharge...from full to empty...all at once. Keep your average discharge below that, and maybe you won't toast them..
PS..the TP's will kill the s400 before it can kill them...should be fun too.
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