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View Full Version : AXI 2808/24 How much can it haul?


Turbojoe
12-16-2005, 01:53 AM
I picked up an AXI 2808/24 during the Hobby Lobby Thanksgiving sale. I'm building a Carl Goldberg Eaglet 50 for electric conversion. I'm hoping to get it into the 30-36 ounce AUW range with a LOT of balsa for ply substitution. Is this motor gonna cut it? I'll be using TP 3S1P 2100's. I'm not looking for a rocket but I don't want something that's an underpowered crash waiting to happen. I just got a CC Phoenix 45 so I can go a little bigger on the motor size if needed. I don't want to have to buy a new battery combo just for this plane if at all possible. I could double up for a 2P setup but want to avoid that if I can. I'm thinking the 2820 is probably going to be advised though.


Joe

Rugar
12-16-2005, 02:10 AM
I picked up an AXI 2808/24 during the Hobby Lobby Thanksgiving sale. I'm building a Carl Goldberg Eaglet 50 for electric conversion. I'm hoping to get it into the 30-36 ounce AUW range with a LOT of balsa for ply substitution. Is this motor gonna cut it? I'll be using TP 3S1P 2100's. I'm not looking for a rocket but I don't want something that's an underpowered crash waiting to happen. I just got a CC Phoenix 45 so I can go a little bigger on the motor size if needed. I don't want to have to buy a new battery combo just for this plane if at all possible. I could double up for a 2P setup but want to avoid that if I can. I'm thinking the 2820 is probably going to be advised though.


Joe

I fly a 28oz SA Groove on that motor proped for 26amps and lots of power, but not overpowered. If you can keep your AUW close to your low range you should be ok, but that 3S2100 is not going to cut it if its a Gen2 pack.

Turbojoe
12-16-2005, 02:40 AM
I fly a 28oz SA Groove on that motor proped for 26amps and lots of power, but not overpowered. If you can keep your AUW close to your low range you should be ok, but that 3S2100 is not going to cut it if its a Gen2 pack.

I was afraid of that. I hoped to use GenII's. I do have two Pro-Lite 2100 packs I could possibly use but I like to reserve them for my T-Rex heli. Remember, the Eaglet is a high wing trainer and I plan to fly it that way. My next glow to electric project will most likely be a .40 size Cessna 182. I know I'll a new power system for it. I'm leaning towards the new motors from E-Flight. They are coming out with a .25 comparable size motor next month. Maybe I should sell the AXI and go with the E-Flight when it's released for the Eaglet? The .40 would be WAY too big so it'll be a later purchase.

Joe

Milton
12-17-2005, 03:27 AM
From there site the max amp draw is 22 amps
3S at 3.4 volts under load = 10.2 volts X 22 amps = 224 watts
4S at 3.4 volts under load = 13.6 volts X 22 amps = 299 watts

With a 36 oz plane the 3S will give you about 75 watts per pound and will fly it but slow and not much vertical

The 4S will give you about 100 watts per pound and should fly very well.

Below is a link to a 19 1/2 pound plane flying on 100 watts per pound.
http://www.eflightbatteries.com/user/milton-rearwind.wmv

I think you will need a 2P for good flight time.
Milton

Rugar
12-17-2005, 03:54 AM
Even though Axi shows 22 amps max for the 2808/24, I push it to 26amps in short bursts as most do, and get approx. 265 watts. Most feel that Model Motors underrates their motors by a fair amount. IF he can get it down to the low 30oz range, and being he is not looking for a lot of power, he may get away with using 3's which would also keep the AUW down over using a 4S pack. His Pro Lights should work and keep him from buying another pack.

Turbojoe
12-17-2005, 02:54 PM
The lowest powered motor I have is 100 watt. Most are in the 150-175 watt range. I have very few planes that are over 16 ounces so I'm used to flying with OVER 100 watts per pound. Maybe I'll just sell off this AXI and get the E-Flight 25 when it comes out. I'll need batteries too but I'll have plenty of power (550 watts) to use the package for other planes in that size range. I hate it when I make impulse buys during sales. :(


Joe

VULTCH120
12-17-2005, 06:36 PM
It has been a while since I had an Eaglet 50 but if memory is correct it used a .25 engine, and had a light wing loading. I use a 2808-24 on my Autokite XP which weighs in at 36 oz. Lots of power with the AXI. I use this plane with live video doing aerial recording. The battery is 3s 4000mah LI-PO from True RC. The MAXAMPS 2100mah Li-POs also work great for me and the price is right.
I think you will enjoy the Eaglet with the 2808 motor.It should have more than enough power. Vultch

Rugar
12-17-2005, 06:53 PM
The MAXAMPS 2100mah Li-POs also work great for me and the price is right.


Same packs I use with mine. Draws the 26amps without even batting a eye.

rclark
12-23-2005, 04:22 PM
All depends on how you wish the plane to fly. The AXI 2808/24 will definitely pull the 36oz plane around. You won't be hovering with it and climbouts will be more like 30-45 degrees (guessing) or so ... but propped for around 26-27A (11" prop) on a 2600 3S1P (10-15C pack) you'll be ok (may even surprise you :) ) . At 27A at 10V, thats 270W/2.25# = 120W/# ..... I like to stay below 30oz with 2808/24 for acrobatic performance, but that's me.... Probably be okay for 'trainer' performance...

rcers
12-23-2005, 04:27 PM
All you need is 50w/lb for this plane. We are forgetting the good old days of e-flight gang!

If you want to fly it like a trainer, that will work great. I fly my mini-telemaster with 7amps and it flies wonderfully at about 55-60w/lb.

Built it light and keep it to mid 30oz and it will do great! As others have said you could push that motor a tad too.

Mike

buzzltyr
12-23-2005, 08:15 PM
Joe,
I'm curious as to how you are doing on this build. Any progress/pics (hint, hint)?
Have a very Merry!
Mark

Turbojoe
12-24-2005, 04:47 AM
I'm really not looking to hover an Eaglet.:D Seriously though, I'm thinking I'm going to be okay for power. With the VERY little I've gotten done so far I'm pretty optimistic. The unassembled fuse wood parts total 2.8 ounces. That obviously doesn't include glue, landing gear, windows or covering. I'm going to use aluminum landing gear instead of the heavy wire. The windows will be acetate and the covering will be SolarFilm. Servos will be HS-81's. I may end up coming in under the 30 ounce target.


Joe

Rugar
12-24-2005, 05:03 AM
I may end up coming in under the 30 ounce target.


Joe

If you do, you will be able to hover it. LOL

Turbojoe
12-24-2005, 01:46 PM
If you do, you will be able to hover it. LOL

VERY good point! :D


Joe

rcers
12-24-2005, 04:57 PM
If you are under 30oz it will fly it very very well.

Mike

TManiaci
12-25-2005, 12:12 AM
I think you'll find the AXI 2808/24 performs better than you expect. Put on a 10x5E and go for it. You'll pull 45 oz's thrust, around 24 amps, ~265 watts, plenty for a 30-35 oz trainer. It'll fly fine there, and surprise you with power. Hardly gets warm with that setup, just make sure you have good airflow for the motor. Your 2100's will do just fine too, just keep WOT runs short and have a ball. These AXI motors are very under-rated, and you can easily push them 150% of rating for short periods with no problem. I won't buy anything else :D .

Merry Christmas!

jperch
01-05-2006, 03:20 PM
Joe,
Sorry if this is late but I think I agree with most of the posts. I have two airplanes with this exact motor. But I am not running it as hot as some have suggested is possible. I run a 9x something prop on 3s Tp2100's gen 2. I use a CCP25 for the ESC so I don't want to push that too hard (although I am certain it could take it). Of course, both of my planes are closer to the 24oz range but one is a Pitts M12. The other is a converted HOB Space walker. Both are pretty near ballistic. The spacewalker for sure is quite overpowered on that setup. I would think a 30ish ounce trainer would fly like a well powered trainer without needing to push the motor.

Just my $0.02

Joe