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FUNJET

Old 07-03-2012, 07:07 AM
  #1201  
moparmyway
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Default RE: FUNJET


ORIGINAL: The1User

Hello everyone,

I have a Funjet Ultra and using the ''power pack'' motor, metal motor mount and prop from Multiplex

My question it does anyone know if the plane flies better with the Multiplex Propeller 6x5.5
( http://www3.towerhobbies.com/cgi-bin...?&I=LXBFBP&P=7)

At $7.49 each is there any benefit to using the Multiplex Propeller over a good cheap APC prop?

Thanks

Joe
I think the plane flies better with the APC E 6x5.5 prop
It will pull a little more power than its "Graupner" counterpart, and give you more thrust.
If max speed is your thing, then a Graupner 6x6 should work great with that setup !!
Old 07-03-2012, 07:18 AM
  #1202  
moparmyway
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Default RE: FUNJET



ORIGINAL: FIREHAWK0-1

Just finished my funjet a week ago running HobbyK 200 amp esc and turnigy heli motor 6s 45-90 c battery 7x5
apc prop fastest thing I seen in a long time vertical is faster than a bottle rocket cool plane
ORIGINAL: FIREHAWK0-1

Just finished my FJ 6s 45-90c battery 200 amp esc and apc prop fastest plane Ive seen
in a long time Turnigy heli motor vertical is faster than a bottle rocket unbelieveable
speed should be around 180 190 range
There is NO WAY your 7x5 prop will get you into the 180-190 range, unless you are measuring your speed in a dive.

For straight and level speeds of what you are stating:
You will need 39,000 RPM's to get your pitch speed to 185mph, and to fly into the 185mph range, your pitch speed MUST be higher than your intended speed by about 10% with a 7" prop.
That brings you to about 43,000 rpm's needed to get you into the 185 mph range.

Prop tip speed formula is:
(RPM * Diameter) / 336.13

(43,000 * 7) / 336.13 = 895mph prop tip speed
The speed of sound is 768 mph.
Your prop tips would be traveling 100 mph faster than the speed of sound ....................................

Are you sure you werent diving ?



Old 07-06-2012, 06:44 PM
  #1203  
FIREHAWK0-1
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Default RE: FUNJET

I am running a funjet on 6s batt. and 200amp esc, 7x5 prop heli motor, i believe it is
running around 190 range super fast I have magnum with western engine Know radars
at over 160 funjet is much faster I will put the gun to it when I get brave enough and a
big piece of plywood to hide behind Look on you tube one guy has onboard pitot tube
showing 186 with the same setup I don't know how acccurate that is but I will find out
soon with the gun.
Old 07-06-2012, 09:15 PM
  #1204  
The Raven
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Default RE: FUNJET

How are you guys securing the motor mount plate to the round portion? Are you using the stock screws or are you gluing or attaching it some other way?

My prop needs further balancing but, it's not out far enough to justify the vibration I'm getting at 1/2+ throttle.
Old 07-07-2012, 06:59 PM
  #1205  
FIREHAWK0-1
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Default RE: FUNJET

no way you sure http://www.youtube.com/watch?feature...&v=Ub9EpgzN6XY
Old 07-08-2012, 12:49 AM
  #1206  
moparmyway
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Default RE: FUNJET

ORIGINAL: moparmyway



ORIGINAL: FIREHAWK0-1

Just finished my funjet a week ago running HobbyK 200 amp esc and turnigy heli motor 6s 45-90 c battery 7x5
apc prop fastest thing I seen in a long time vertical is faster than a bottle rocket cool plane
ORIGINAL: FIREHAWK0-1

Just finished my FJ 6s 45-90c battery 200 amp esc and apc prop fastest plane Ive seen
in a long time Turnigy heli motor vertical is faster than a bottle rocket unbelieveable
speed should be around 180 190 range
There is NO WAY your 7x5 prop will get you into the 180-190 range, unless you are measuring your speed in a dive.

Are you sure you werent diving ?



ORIGINAL: FIREHAWK0-1

no way you sure http://www.youtube.com/watch?feature...&v=Ub9EpgzN6XY
yeah pyro, its a clear dive, doppler lines are very curved, video shows it well.
I bet if you were dropped out of a plane at the height he was, you too would go 189 mph.

Like I said ................ a dive

Nothing wrong with diving at all.
Just state it was a dive so others dont burn their motors
Old 07-09-2012, 01:49 PM
  #1207  
FIREHAWK0-1
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Default RE: FUNJET

I sliced a 4mm plate off of alum. roll stock drill and tapped 4 3mm holes on the out side
of the end of the black cone and shaped it like a clover leaf for air cooling seems to work
well then just glued it on the back of the plane.
Old 07-09-2012, 01:55 PM
  #1208  
FIREHAWK0-1
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Default RE: FUNJET

moto Qty STATUS
TR31264-1600 Turnigy 500 H3126 Brushless outrunner 1600KV
motors are cheap at least the one I am running 19.00 plus shipping
Old 08-01-2012, 03:31 AM
  #1209  
The Raven
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Default RE: FUNJET

Hi Guys, I'm having motor balance problems and need some help.

I'm using the 'Hobbycity combo' for my FunJet Ultra and despite carefully balancing props cannot get past half throttle without serious vibration. Note this is static ground testing, it has yet to maiden. I'm aiming to use a APC 7x5 nitro prop.

How are you fitting the round section of the motor mount to the fuse? I've used what I'd consider more than adequate CA (not drowning, just standard amounts).

How do you fit the alloy motor mount to the plane, I've used the stock screws but does the adjustment screw need to be replaced with an embedded screw?

Is more reinforcing/glue required?
Old 08-14-2012, 11:56 AM
  #1210  
moparmyway
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Default RE: FUNJET


ORIGINAL: The Raven

Hi Guys, I'm having motor balance problems and need some help.

I'm using the 'Hobbycity combo' for my FunJet Ultra and despite carefully balancing props cannot get past half throttle without serious vibration. Note this is static ground testing, it has yet to maiden. I'm aiming to use a APC 7x5 nitro prop.

How are you fitting the round section of the motor mount to the fuse? I've used what I'd consider more than adequate CA (not drowning, just standard amounts).

How do you fit the alloy motor mount to the plane, I've used the stock screws but does the adjustment screw need to be replaced with an embedded screw?

Is more reinforcing/glue required?
You might be having balance issues if you:
1. are using a set screw type of prop adapter ......... collet type works best
2. Have a bent shaft, regardless if its new or not, an out of balance prop can bend a 3.2mm shaft if turned at high enough RPM's
3. Have a bent prop adapter ............... replace adapter and see if vibration goes away
4. Havent balanced the prop correctly ......... did you use a magnetic balancer ?

Motor to fuse is like you did, standard CA .......... you could "paint" epoxy at the point where they meet to help keep it secured after the CA is dried

Old 01-18-2014, 05:22 AM
  #1211  
SACKRC
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Originally Posted by gryphon
alex_scratch_built,

16/25/3 is a 1700kv motor.
16/30/2 was tested closer to 2225kv by me.
16/40/1.5r was tested closer to 2300kv by me.

I think depending on prop size that people want to run and limited airflow in a funjet, it would be great and safe to go with 16/40/1.5s if 6s is the goal....similar to it with a bit lower kv would be 16/35/2 (one of these is sitting on a dealer shelf in usa)......16/25/3 on 6s has been done on smaller 6s packs and reported at 150 mph just like you said.

***the motors you listed can swing decent prop at high speed on 6s but airflow to cool motor is lousy in funjets.........then again some people want to run 4.75x4.75 props at insane rpm. I'm not sold on that but if that is the goal maybe the 2200-2300kv motors that you listed could get by in a funjet.

I rather see 5.5x5.5 as opposed to 4.75x4.75 if trying to get to 180 mph range....because i'm not so sure that the little prop can make enough thrust to overcome the drag of the airframe at such high speeds.


___________________________________

blkz2801,


the two dealers in usa that can order any of the regular or special motors are new creations rc in texas, and efflux rc in california.

Efflux would ship to other countries...he (gary) has a little better prices and quicker reactions to orders.

New creations (kirk) has the 16/35/2c 5mm shaft in stock as of 2 days ago.

New motors could be built and delivered by manufacturer in europe in 4-5 weeks or so after the dealers make the request.

16/35/x $135
16/40/x $145

letter ā€œcā€ means 5mm combat shaft, which ensures no bent shafts unlike other motor manufacturers.....usually free option, or at most extra $5 pending dealer and which motor such as 16/25/x

pm me for links and to get my attention.

All 28mm diameter mega motors can get the ā€œeā€ option which means the motor will get 5mm longer rotor/magnet to lower kv by about 6% while maintaining same winding. This is roughly a $10 option.
For example 16/30/2ec will get 35mm rotor (to lower kv 6%) and it will be 5mm combat shaft.
**at this point 16/40 will not have ā€œeā€ option because mega does not want to build 45mm rotors.


Gryphon
purchased a 16/35/1 , can this work. If what prop or was it a mistake? Thanks rich b.
Old 01-18-2014, 05:24 AM
  #1212  
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Purchased a 16/35/1, for my fun jet, can this work. If so what prop? thanks rich b.
Old 04-03-2014, 09:34 AM
  #1213  
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How are you all launching the Funjet?
I have a Ultra and finding it is a nightmare to launch, tried full power, half power, all kinds of angles etc etc, but it still rolls violently!
They fly great, but the fun has gone knowing its a gamble on getting it airborne.
Old 04-03-2014, 11:04 AM
  #1214  
Xairflyer
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Never had that problem, try trimming it on next flight at low speed.

I always launch mine full power and have a bit of up elevator programed on a switch for launch when it is climbing away I flick off the switch
Old 05-03-2014, 06:04 AM
  #1215  
pylonboy
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Bungee...................no muss, no fuss when I am alone.
Old 05-03-2014, 06:40 AM
  #1216  
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Originally Posted by turbinepeter
..... all kinds of angles etc etc, but it still rolls violently! .
Tried 75* to 90* ??? Cause then its just spinning on a vertical axis going straight up

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