Chuck322

My Feedback: (11)

I have a Kyosho spirfire and want to make it Epowered (56"span, 88oz)
Thought abour AXI 4120/18, APC 12x6 and 6s2p 10 c (2x 3s parallel) Dymond LiPo.
Gives 9600RPM, 510 W in, 430 W out, 28A, 94oz static, 72oz flying all calculated.

What do you think,
Chuck

Greg Covey

Hi Chuck,

For an 88oz Spitfire with good to high performance, let's use 100w/lb power level.

88oz = 5.5lbs so take 5.5lbs times 100w/lb to get 550 watts needed. This is your target motor power class; 550 watts.

An AXI 4120/18 motor can burst current to 40amps, so when we use a 5-cell Lithium pack, the voltage under load should be 3.5v * 5 or 17.5v. To get power, multiply voltage x current, so 17.5v x 40amps = 700 watts burst power. This means you can easily obtain your 550 watts using an AXI 4120/18, 5-cell Lithium pack capable of 40amps continuous, and around a 14" prop.

Good luck!

Chuck322

My Feedback: (11)

Thanks Greg

Chuck322

My Feedback: (11)

I did some new calculations, because 6s3p is too heavy and expensive for this small plane and it would be 5oz heavier compared to built it with a Saito 82 I already have.

Now:
Airframe empty 60oz
lighter servos: 2x JR 368, 2x JR 3041, 1x Jr 513 (retracts)
Axi 2826/10: 181g instead of 320g for the 4120
Phoenix 60: 58g
Dymond 12C 2100 4s2p total: 340g vs 600g for 6s3p - best thing: only 120,-$ (59,- for each 4s pack)
total weight: 2340g or 82.6oz or 5.16lb before it was 100oz

Motocalc:
APC 13x7, 42.9A, 13.7V, 586 W in, 381 W out, 8063RPM, 75oz thrust at 4500ft, 25°C, 1020hPa.

I think 75oz thrust is enough to fly a 82 oz warbird around.
Will it be enough??

Oh and I forgot,
The Great Electric Motortest at www.flyingmodels.org/index_en.htm states:

APC 13x6.5E at 11.2V, 42.1A, 472W, 7660RPM, and 82.7oz thrust for the Axi 2826/10.
Chuck

Greg Covey

The AXI 2826/10 should work fine but I would recommend using only a 3-cell Lithium pack instead of a 4-cell pack. Many of these motors are over-rated and you need to pay warning to the fact that it will heat up and have a greatly shortened lifespan.

I have flown the 6lb Graupner Taxi Cup II and the 3lb World Models Fun World EP using the following setup without issues.

[ul][*] AXI 2826/10 motor[*] Jeti 40-amp ESC w/BEC[*] 3-cell Kokam 3.2AH pack[*] APC 13x8 e-prop
[/ul]

Cubano8

I've purchased the latest Kyosho Spitfire that came out, and I'm in the process of converting it to electric. I am going to be using an AXI 4120/14, instead of an AXI 2826/10 for the only reason of balancing the model. I've converted an old global spitfire, with similiar size, and used a 2826/10 on it, only to add weight to the nose to get it to balance properly.

I've been using hitec 225 servos, and PU glue to lighten it up, as much as I can, but so far with the batteries it looks like its going to come out to 6 lbs or 96oz.
The only thing I don't like about the new Kyosho spitfire is the ugly blue color they're using on the bottom of the plane. I had to airbrush it with a gray color to get it in the right color scheme.
Hopefully it should be a good flyer.
I did add the retracts to it too.

drksyd

I'd like to see your progress on the Spit. I just got one from eBay but I think it's the older version. What's the difference between the new and the old?

kris1

I would agree with Cubano8. I have a PCM Pelikan Wildcap. It is a 60" plane and I am powering it with a 4120/14 and 4S1P flightpower 3700 Liop. I am using an APC 14 x 10e and it gives an AUW of 4 1/4lbs. I am drawing approx 45A staic so I would guess 600W ish. The plane will give me flights of 12mins and this all aerobatics. The p[lane has unlimite vertical and will go approx 55 to 65 mph flatout on the level.

The heavier motor and and the smaller cell pack will help with balancing with the short nose.

Cheers

Kris

Cubano8

I'll post some detailed pics, as soon as I get my digital camera working again

Cubano8

Here's a pic of the original coloring. I could only take the picture of the box photo, since I already painted the bottom of the plane.

Cubano8

Here's the pics of the motor, motor mount, and esc install. Also pics of the cowling, where I made an air intake, and glued in an air deflector for the motor and esc.

Cubano8

Here's the pics of the fuselage hatch opening, the hatch, and the latch mounted to the hatch.

Cubano8

Here's pics from the top of the fuselage hatch opening, showing the Li-Po battery tray, which is made of 1/8" plywood. It also has some slots cut out on the sides, so I can run velcro straps through them to support my Li-Po batteries. I also added a door in front of the tray which is hinged, for my RX battery( since I'm not going to use a UBEC). The battery will be wrap with foam to give it a more snug fitting.

Cubano8

This is the bottom view, showing the bottom of the tray, and its support beams. Also the rudder and elevator servo installation.

Cubano8

These are pics of the bottom of the wing, showing the retracts extended and retracted. I used Tamiyas XF-53 Neutral Grey for the bottom color. I dont think it is historically accurate as far as the color goes, but I had a few of these bottles around, so I had to put it to good use.

Cubano8

Here's where i'm at with it so far. The canopy color that I'm using is, Tamiyas XF-67 Nato Green, which closely resembles the green covering on the plane. The wheel size is 2 3/4, since I fly off of grass. It would be difficult to go with 3" wheels without have to dremel in the spar or the leading edge of the wing.
I'm still waiting for my Li-Po to arrive, and I still have to work on getting some more ventillation it. I have to make a exhaust vent hole on the back of the fuselage, and I was thinkin of probably using the plastic exhaust that come with the model to hide some openings on the cowling, also for air venting.

Cubano8

drksyd,

I have read in some posts that the older version covering was affected, if left out in the sun for too long. So you might want to be careful. I don't know if the covering on my model differs from yours.

Cubano8

If I would to do it all over again the only thing that I would change, is the front cut on the hatch, which should have been angle so I could add a front lip for easier removal.

drksyd

Wow, that's a lot of pics. Will be very helpfull when my time comes around.
Which retracts are you using?

Cubano8

I'm trying out the H9 retracts, which I heard they were strengthen up a bit. I also went a bit longer on the retracts, thinking I would need it for prop clearence, but ended up with a lot of that. I just hope the longer retract wont make it more tippy. So I believe any regular 40 size retract would be fine.

drksyd

Hopefully the longer gear works for you, if not get the largest wheels you can fit on it. I think I'll look into some air units if it doesn't cost too much. Actually, I could make use of the 9303's servo delay feature to slow the retracts down. What's cool is you can adjust the rate in both directions.

Kelvin

I converted the old version a couple of years ago.

Heres my thread on Ezone

[link=http://www.rcgroups.com/forums/showthread.php?t=131420]Kyosho Spitfire Conversion[/link]

I used a Hacker B50 10L, 5.2:1 and 14x10 prop. My current battery is a 5s4p Thunderpower 5300. It weighs about 6lbs 2oz.

Here is a video of it flying from last years Arizona Flight Festival.

[link=http://kelvin.rchomepage.com/AEF_Spit.mp4]Kyosho Spitfire Video[/link]

I hope this info is useful.

Thanks,

Kelvin

Chuck322

My Feedback: (11)

Cubano8:

Could you tell me, if the new Kyosho Spit has the same sticky film covering as the older version or is it good iron on covering?

Chuck

Cubano8

It has the iron on covering. I left it in the Sun twice for a few hours, just to see if it was affected at all, and to my surprise there wasn't even a wrinkle. I am very happy with the new Kyosho warbird line. I'm looking forward for the release of the new ME-109.