MX400

MX400
View related threads: (in this forum | in all forums)

Logged in as Guest

Users viewing this topic: none

Printable Version

All Forums >> RC Helicopters >> Electric RC Helis >> Helimax >> MX400

Page: [1] 2 next > >>

Login

Message

<< Older Topic Newer Topic >>

MX400 - 3/3/2007 4:08:45 AM

rwj

Posts: 62
Joined: 12/14/2002
From: kenosha, WI, USA
Status: offline

I am using a 401 and a futaba super 8uh radio. What do all of you have your delay and gain set at? I can't get the tail to stop wagging. also what is your throttle curve set at? Maybe my head speed is to low.

RE: MX400 - 3/3/2007 5:52:35 AM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

I have a Futaba GY240 gyro in my MX400 Pro, and the gain is pretty high at around 75%. The trouble may be with the stock tail rotor. Mine was wobbly and the blades weren't running true. I replaced the hub and grips with Align Trex parts and went with carbon tail blades. I also replaced the wire tail pushrod with a carbon rod which is stiffer and lighter. Getting the tail smooth and free of slop will help the gyro do its job and make it easier to set up.
I'm also running a Castle Creations Phoenix 35 speed control in governer mode. I dialed in a headspeed of 2400rpm. The governer holds the speed constant and the only curves I set are pitch curves in all three modes.

Jesse

< Message edited by whstlngdeath -- 3/3/2007 5:55:04 AM >

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to rwj)

RE: MX400 - 3/3/2007 1:43:05 PM

rwj

Posts: 62
Joined: 12/14/2002
From: kenosha, WI, USA
Status: offline

Now I am not using a govener so I would set up my head speed by using my throttle curves correct or am I wrong. Thanks for your input.

(in reply to whstlngdeath)

RE: MX400 - 3/3/2007 3:31:41 PM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

Both the throttle and pitch curves will affect the headspeed. Here are some websites with lots of good info on setting up these mini helis:

http://x400tuning.com/index.htm

http://www.trextuning.com/index.php

Go to their setup sections to see how others setup these helis. You will have to find a way to tach the blades to get a accurate RPM reading. The best way would be to find someone local where you live to help you with the setup. Otherwise, it can get pretty frustrating trying to dial it in.

Jesse

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to rwj)

RE: MX400 - 8/21/2007 10:02:50 PM

Posts: 234
Joined: 1/13/2004
From: Blaine, MN, USA
Status: offline

what is the target head speed for the MX400

(in reply to whstlngdeath)

RE: MX400 - 8/21/2007 11:56:31 PM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

hobby_man

I have mine set with a governor at 2400 rpm. You have to be careful that you don't overspeed the system. The tail rotor is turning about 5 times the rpm's of the main head. I've heard of tail hubs exploding as well as head parts. If you don't have the metal head pieces, I would limit head speed to maybe 2100 rpm.

Jesse

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to hobby_man)

RE: MX400 - 8/22/2007 1:03:32 AM

Posts: 234
Joined: 1/13/2004
From: Blaine, MN, USA
Status: offline

quote:

ORIGINAL: whstlngdeath

hobby_man

I have mine set with a governor at 2400 rpm. You have to be careful that you don't overspeed the system. The tail rotor is turning about 5 times the rpm's of the main head. I've heard of tail hubs exploding as well as head parts. If you don't have the metal head pieces, I would limit head speed to maybe 2100 rpm.

Jesse

how do you set the governor at 2400??

I have the cc esc set at high gov,
motor is a hacker a20-6xl 2500 kv 11.1 volts
138t main gear 16t pinion 138/16=8.65

2500 x 11.1 = 27750rpm les 10% = 24975rpm / 8.625 =2895 rpm head speed

the math says I am over reving it. a 2100 3s lipo will only last 5 minutes, that syas I am pulling 25 amps.

um, I will reduce my throttle curves on my DX6 to 0-50-50 and see what I get.

(in reply to whstlngdeath)

RE: MX400 - 8/22/2007 1:15:57 AM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

You need to have someone tach it for you with a optical tach while you hover it. Get into the transmitter programming that lets you set the throttle curve at whatever mode you want. To set it up for governor, set the first point of the throttle curve at "0". This lets the esc "see" a throttle-off condition so that it can arm. Then you set the rest of the throttle curve points to whatever percentage gives you the headspeed that you are looking for. My Futaba 8U transmitter is set like this on my throttle curve for normal mode, (hovering): 0--78-78-78-78. These are my five points of the throttle curve in normal mode. I arrived at 78% for the points by having some one tach it in the air, and adjusting the throttle curve until it tached out to my 2400 rpm. This is all trial and error, as each transmitter will be set to whatever percentages it will need to give you the desired headspeed. You can set the same throttle curves for idle up the same as norm, or you can experiment within the limits of your particular heli. Some flyers like to bump up the throttle curve when switching from norm to idle up. I leave mine the same, as I'm not yet good enough to need the change.

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to hobby_man)

RE: MX400 - 8/22/2007 1:38:59 AM

Posts: 234
Joined: 1/13/2004
From: Blaine, MN, USA
Status: offline

the DX6 I ahve has 3 pitch and THL curves.

I set the THL curve at 0-50-50

the blades tracked, this was not happening before

the battery last 8 minutes, it was 5 min

I still am getting a lot of heat on the motor and some swelling of the lipo

from what I am reading at other sites, if I go to a 12t pinion from a 16t I will reduce the tork (amps) and intcrease motor rpm with out increasing the head speed.

Enter The Number of the Teeth of Your Heli Main Gear: 138
Enter the Pinoin Teeth: 12
Enter Your Motor KV: 2500
Enter Your Battery Voltage: 11.1
Enter the Efficiency Rate (. 8 for 80% or .9 for 90%): 0.8
Estimate Head Speed is: 1930

(in reply to whstlngdeath)

RE: MX400 - 8/22/2007 1:51:41 AM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

I use these headspeed calculators:

http://www.readyheli.com/Online_Headspeed_Calculator_s/81.htm

A 16 tooth pinion is way too much for that little heli. I'm running a 12 tooth, with a outrunner motor and C.C. Phoenix 35. The Kv of my motor is hotter than the stock motor the Heli-Max comes with, but the stock motor and speed control tend to overheat. If your li-pos are ballooning out, don't use them in that heli until you figure out the amps. I suggest you use a watt meter to see how many amps it's really pulling.

Jesse

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to hobby_man)

RE: MX400 - 8/22/2007 2:05:04 AM

Posts: 234
Joined: 1/13/2004
From: Blaine, MN, USA
Status: offline

the one I have is a xcell spread sheet, I can do it with a cal. this is just faster.

why do you say 16t is too much, because of the head speed?

out runner motorr is a hacker a20-6xl 2500 kv 11.1 volts with a cc phoenix 45

I will put a watt meter on it, I take it I tie the heli down with the meter on it and run it up???

PS I did smoke a lipo on one of the cell's this weekend as well messing with this used POS

(in reply to whstlngdeath)

RE: MX400 - 8/22/2007 2:12:43 AM

Posts: 234
Joined: 1/13/2004
From: Blaine, MN, USA
Status: offline

http://www.astroflight.com/store/store-type-tem.html?item=products:af-101d&sid=0001lhoOCuwzvHsyGM2y2u3

like this for a watt meter

what about a voltmeter will it measure watts

(in reply to hobby_man)

RE: MX400 - 8/22/2007 2:17:07 AM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

Yea, it's kind of like taking a amp reading on a fixed wing airplane, only the "prop" is a lot bigger and more dangerous. Maybe 16 tooth pinion isn't too far off, since the kv of your motor is low. Setting these things up is such a balancing act. There's too many things that can change your setup, from length of main blades, to the weight of the heli, to even the brand and quality of the batteries. Just when you think you have it set up, something changes. Honestly, I'm using my MX400 just to learn on, then I'm moving on to glow helis.

Jesse

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to hobby_man)

RE: MX400 - 8/22/2007 2:18:53 AM

Posts: 914
Joined: 5/25/2002
From: Catoosa, OK, USA
Status: offline

Yea, that's a good watt meter. You can measure amperage with a voltmeter, but you have to do the math: power(watts) = current x voltage.

Jesse

_____________________________

"Greater cruising speeds are possible, but the size of the earth does not warrant greater speeds." - Igor Sikorsky

(in reply to whstlngdeath)

RE: MX400 - 8/22/2007 2:32:43 AM

Posts: 234
Joined: 1/13/2004
From: Blaine, MN, USA
Status: offline

I was into glow heli's about 15 years ago,,,before the internet, man I'll tell ya I was on my own, no one to ask.

I got sick of the mess with the glow, and the noise, this heli I can fly here in town and at the lake and no one knows I am flying it.

I hear you on the set up, I have been at this for months, it started with a AXE CP, I was flying the rotors off is so I got into some thing bigger,,,,,what a mistake, now all I do is work on it

a couple diff. sites are selling the -trex deliverd and set up,,,radio programmed and redy to fly.

you tell them your ability and thats how they set it up. put the blades on it and install the battery and fly it.

they get 75.00 to do all of that, heck I can trash 75 dollars in parts on a weekend

(in reply to whstlngdeath)

RE: MX400 - 8/22/2007 2:35:31 AM