tonywayne

I just got a new Ulmer-rc Blink. Wing span 18”, currently the airframe weight with covering is 2.5 oz that’s with no hardware or anything installed yet. The popular power plant is .049 glow. I would like to try electric. What would be the best elec setup for all out speed? I have never ran elec before so I need motor size and battery.

airraptor

My Feedback: (66)

well to keep it light and fast i would go with a little screamers "park jet motor" a 5x5 prop and a 1100-1500 25c battery should do 100mph or so.

tonywayne

I’m not familiar with the c rating on batteries. Is this lipo batteries? How many volts?

Razor-RCU

My Feedback: (50)

Sweet, keep us posted!

(I no virtually nothing about E power, sorry)

haikt

My Feedback: (11)

C rating is the amount of amps the batt. can give. lets say if you have a 1000mAh batt. at 10C rating this will give you 10 amps without getting damaged if you have 1000mAh at 25C you will get 25 amps. this all comes down what motor and prop you will use. lipos are 3.7V per cell so to go fast you will need like a 3cell (11.1V) and lets say mega 15-6-3 and 5x5 prop this will pull about 25-30 amps at 11.1 volts so you will be ok with 25C 1000mAh pack. also brushless motors have a KV rating that you need to know about. KV is 1000rpm per volt. so if you have 1000kv motor you will get 11000rpms with a 11.1V pack or 7300 rpms with 2 cell (7.4 V) pack. to go fast you need as much kv and volts you cen get away with, but there are many problems more volts and volts you get much more amps, then you have batt. and ecs problems.........
hope this helps some

airraptor

My Feedback: (66)

try these instead from towerhobbies

http://www3.towerhobbies.com/cgi-bin...?&I=LXLWW8&P=0 motor

http://www3.towerhobbies.com/cgi-bin...?&I=LXMWK3&P=M prop adapter

http://www3.towerhobbies.com/cgi-bin...?&I=LXKSY3&P=0 speed control

http://www3.towerhobbies.com/cgi-bin...?&I=LXRVP8&P=0 battery


run a 6x4 prop and should be pretty light and sorta fast

cncswiss1

if you want to keep it light :

MOTOR:
http://www.hobbycity.com/hobbycity/s...idProduct=6584

the rest of the gear on it
http://www.hobbycity.com/hobbycity/s...idProduct=4318
http://www.hobbycity.com/hobbycity/s...idproduct=2135
http://www.hobbycity.com/hobbycity/s...idProduct=2050
http://www.hobbycity.com/hobbycity/s...idProduct=5459
http://www.hobbycity.com/hobbycity/s...idproduct=6507

vid of this gear on a plank , with the 2c, with the 3c it rips!
http://www.youtube.com/watch?v=ioyn8G5l4Dk
excuse the 6 yr old video man (fisher price video )

combatpigg

My Feedback: (3)

A 1.5 oz glow engine and 1 oz worth of fuel can get this plane going with a 4.2x4 prop at about 30,000 rpm, and it'll run on an oz for about 3 or 4 minutes flat out. This is the level of performance that I would like to see electric beat, in the same size package.

cncswiss1

lowbuck lekky setup
24g HXT 3000kV actual measured data
4.1x4.1 APC
24,000 RPM
10.32V (Vmin)
188W sustained 30 sec.
17.8A peak
93 mph pitch speed

http://www.hobbycity.com/hobbycity/s...idProduct=2103
BATTERY 94 GRAMS
http://www.hobbycity.com/hobbycity/s...idProduct=5453
MOTOR 24 GRAMS
http://www.hobbycity.com/hobbycity/s...idProduct=4312
speed control=20 grams

138 grams of gear= 4.86 oz.. heavier than the 2.5, but no throttle servo needed, and no fuel proofing needed.
and high dollar nice stuff will be lighter , you could shave an oz or so off of that.

well i tried[:@]

combatpigg

My Feedback: (3)

Thanks for those links. Last time I tried similar sized stuff it was disappointing to only get full throttle for half a minute then spend the rest of the flight at 75% power. IIRC, it was a 15C pack.

cncswiss1

I still can't find the darn needle on these brushless jobs.. they'd be so much easier to run if I could lean em out instead of trying every prop under the sun to get what I like.

If you want to get full throttle and stay at full throttle get a polyquest pack, ~40c

http://www.hobbycity.com/hobbycity/s...idProduct=5586
should be good for 18 amps for ~2 minutes
bigger will fly longer but the mass adds up fast!

actually the motor I have been eyeballing is:
http://www.hobbycity.com/hobbycity/s...idProduct=6316

at 4000 kv it should be good for ~ 30k on the same prop @ ~25A

I know , enough of the hobby city links, but with kids I have to fly the cheap stuff for now. I have to be happy with just drooling over over the nice stuff (neu motors are astounding!)

evan-RCU

You have to be carefull on what you get from hobby city. Many items, especially motors, are over spec'ed.

This looks to be the size of my mini-dust and I don't see an electric setup that would beat the .061 & .074 glow set ups I run on it. I'd be interesting if you do find a good set up because throttle would be nice.

cncswiss1

yes some of it is over rated, or reviewed by folks that don't mind smoking one now and then. but with some testing and patience some real gem's can be found. sort of like shopping at biglots, you have to wade thru the junk to find the good stuff.

from castle creations site

airraptor

My Feedback: (66)

a park jet motor 3 cell and apc 6x5.5 will be faster than the glow stuff easily. this setup with a 1500 25+c batt wil easily go over 120.

this will be the lightest and fastest set up

tonywayne

bump.

Julian537

My Feedback: (9)

Tony,

did you ever get this thing in the air?

z06kal

Combatpigg which glow engine would this be?

jetdryvr

I'm not too sure if it's too big for that plane but if a mega 16/15/3 or (16/15/2 if you're wacko a 4.1 X 4.1 or so and an appropriate smaller speed control (1800 to 2100mah 20C or 30C pack) would kick some serious but for way more than 30 seconds. That plane is not as clean as a mongrel or voodoo but I fly at 75-100% throttle for the whole flight which is around 4-5 minutes. At 150-170mph with a plane that small, I'm done before the plane is. There are definitely some electric setups that will surprise you,
Erik

combatpigg

My Feedback: (3)

z06kal, an original KillerBee will turn a 4.2x4 prop 30,000. Shave the insides of the piston skirt down to paper thin and lap the crank to the case if needed. A Norvel AME will produce similar rpm on the same prop. The Cyclon and Fora .049-.061s will put out more like 35,000. The King of the Hill is the piped GZ .061, I've seen 42,000 out of it. That's 700 cycles per second. It has a Satanic howling sound to it.

tonywayne

where would the CG be?

tonywayne

Here it is. Motor HXT 24gram 3000kv, 4.1X4.1 E prop, 3cell 610mah, weight with batt is 7.2oz. havnt flown it yet but static test with tach showed 24,000 rpm.

cncswiss1

ditch the O-ring prop saver mount,good for slow flyers, not so good for speed,it is robbing rpm from you, i bet you'll find 1500+ more rpm static with that change alone.

I was pulling ~18 amps with that motor and a 4.5" folding prop, are those 30C 610's? you may want a bigger battery as well, and may see more RPM with that change as well if the voltage was sagging with too much of a C draw..

just my .02, mileage may vary.

that motor is a stud with 'a 7-3.5 on 2c
on 3c i have tested a 5.5" with good cooling and didn't cook it.

*edit for crummy spelllling

tonywayne

its a 20c. Ill keep it as is for the first flights to get use to it. never flown anything this small and fast befor. im worried about damaging the motor shaft or prop on landing not useing a prop saver.

combatpigg

My Feedback: (3)

Looks nice Tony, but those push rods won't cut it. A neat solution is to find C/F or F/G tubing that is a tight fit over that wire.....or else place at least 1 guide in the middle of each "run". You want precise control both pushing and pulling on the linkage.

tonywayne

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