HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Oct 02, 2012, 08:47 PM
Planes in flames,,,
jetpackninja's Avatar
Gravity Sucks
Joined Aug 2010
3,564 Posts
Where is your cg?
Measure it by balancing it from the bottom and let us know how far back it is from the nose
jetpackninja is offline Find More Posts by jetpackninja
Reply With Quote
Sign up now
to remove ads between posts
Old Oct 02, 2012, 10:40 PM
Registered User
KC Flyer's Avatar
Lee's Summit, MO USA
Joined Jan 2001
387 Posts
Good luck with the rewinding chaps!

It really is the only way to go unless you have $60 or so to buy something like a custom wound MicroDan motor. I would start out with 9 turns but feel free to try 8 turns if you want a little more power (my flying buddy swears by 8 turns). Definitely don't mess with low temp 26 ga RadioCrap wire. Use 24 ga MD wire for either 8 or 9 turn rewinds

I do agree with Blunight that you shouldn't use 25c 1300 LiPos. I've had good luck with the 45-90c NanoTechs (but not the 25-50c ones as they puff). The motor will pull a little over 30a with fully charged LiPos and no airspeed (prior to launch).

I've had mixed luck with a HK SS 25-30a Card Programmable ESC. On a very hot day (+100 F), it overheated on my 8.5/9 turn motor and slowed way down (protection mode). I replaced it with a 40a ESC and used the overheated one on my son's plane with a 9 turn motor (but he doesn't fly as fast as me). It hasn't given him any problems. Be sure to set timing to high as it will screech if not.

Although I haven't used one on an Assassin yet, I currently like these F-30a ESCs as they are what the smart guys over in the quadrocopter threads are using (and even reflashing with custom firmware).

They have all "N" FETs rather than combination of "N" & "P" FETs like the HK SS. Having all "N" FETs is supposedly more efficient (less heat generated). They also have an external oscillator (whatever that means) which is supposed to be better than relying on the internal oscillator that the HK SS has.

Be sure to get the corresponding Programming Card to make it easy to change settings.


Quote:
Originally Posted by blunight View Post
You can rewind the Emax motor for 300 watts with a 7x6 prop...See KC Flyer's post #5847. I just ordered the wire to try this...

One of my Assassin's has a Motrolfly 2210/2200 motor. 311 watts on a 6X5.5 prop and 30A static.

At that power level you need a 40c 1300 mAh battery - it will easily puff a 25c battery (ask me how I know) but man o' man does that thing rip!
KC Flyer is offline Find More Posts by KC Flyer
Last edited by KC Flyer; Oct 02, 2012 at 11:03 PM.
Reply With Quote
Old Oct 03, 2012, 05:59 AM
wait, there was a tree ?!?
moray's Avatar
Switzerland, ZH, Oberengstringen
Joined Jun 2012
155 Posts
Are you still using the 7x6 prop with the rewound 2812 8t 24ga or do you prop it down ? I have rewound one with 24ga and 9t but I had a hard time getting 9 turns in neatly. Tbh it was my first time rewinding a motor.
moray is offline Find More Posts by moray
Reply With Quote
Old Oct 03, 2012, 06:15 AM
wheeeeee!
elCapitan's Avatar
United States, UT, Provo
Joined Oct 2011
916 Posts
I for one am still using a 7x6 on the re-wound red motors. Works great! So much more power!

Yeah, it's difficult to get 9 winds in. What I found to work was to get 8 winds in nice and neat from the inside out, (which still takes some work, but is totally doable) then use the 9th wind over the top to move back towards the center, on its way to the next tooth.

...I don't know how much neatness really effects performance, but if you're a bit OCD on your rewinding, it works
elCapitan is offline Find More Posts by elCapitan
Reply With Quote
Old Oct 03, 2012, 07:57 AM
wait, there was a tree ?!?
moray's Avatar
Switzerland, ZH, Oberengstringen
Joined Jun 2012
155 Posts
Trying out 8t on the next rewind and check the amps on 7x6 afaik it was arround 32a on 9t.
moray is offline Find More Posts by moray
Reply With Quote
Old Oct 03, 2012, 08:34 AM
Chess club geek with wings
blunight's Avatar
United States, FL, Cape Coral
Joined Aug 2008
1,066 Posts
To those with Emax motor knowledge...

KC flyer thanks for the ESC info!

We had a great combat session last night but I ended up breaking the shaft of my Emax motor in half on a hard hit!

Anyone know of a replacement shaft that will work?

Our club has seen 2 of these shafts break in the last month of combat so it looks to be a somewhat common occurrence.
blunight is offline Find More Posts by blunight
Reply With Quote
Old Oct 03, 2012, 08:44 AM
Registered User
Joined Jun 2009
391 Posts
Motor shaft

Quote:
Originally Posted by blunight View Post
KC flyer thanks for the ESC info!

We had a great combat session last night but I ended up breaking the shaft of my Emax motor in half on a hard hit!

Anyone know of a replacement shaft that will work?

Our club has seen 2 of these shafts break in the last month of combat so it looks to be a somewhat common occurrence.
Check these guys out, they have a lot of brushless motor parts.
http://www.headsuprc.com/servlet/the...FTS/Categories
Good luck.
Chico John is offline Find More Posts by Chico John
Reply With Quote
Old Oct 03, 2012, 10:29 AM
Planes in flames,,,
jetpackninja's Avatar
Gravity Sucks
Joined Aug 2010
3,564 Posts
Quote:
Originally Posted by moray View Post
Are you still using the 7x6 prop with the rewound 2812 8t 24ga or do you prop it down ? I have rewound one with 24ga and 9t but I had a hard time getting 9 turns in neatly. Tbh it was my first time rewinding a motor.
Yeah- But that's what makes it work so well. The theory here is to get as much copper in between the stator teeth as possible- that's where the efficiency comes into play. I take a plastic credit card and slide it through to pack the windings in.
9 turns is indeed tight but doable. If you are ever suffering from insomnia there is an entire thread devoted to rewinding motors here somewhere on RC groups.
jetpackninja is offline Find More Posts by jetpackninja
Reply With Quote
Old Oct 03, 2012, 10:58 AM
Registered User
Joined Jun 2011
123 Posts
One important thing to do is get all of the glue out of the teeth to make sure you have more room for the windings nears the middle of the motor. The motors I got from headsuprc had a lot of glue on them and I have to spend a good 30 minutes chiseling it out. The hobbyking motors only took about 2 minutes. Not sure why the difference, but they must produce them in different plants, or just at different times.
Whomprat is offline Find More Posts by Whomprat
Reply With Quote
Old Oct 03, 2012, 11:00 AM
Registered User
Joined Jun 2009
391 Posts
Looks.

Quote:
Originally Posted by jetpackninja View Post
Yeah- But that's what makes it work so well. The theory here is to get as much copper in between the stator teeth as possible- that's where the efficiency comes into play. I take a plastic credit card and slide it through to pack the windings in.
9 turns is indeed tight but doable. If you are ever suffering from insomnia there is an entire thread devoted to rewinding motors here somewhere on RC groups.
When that stator is spinning and pulling the Assassin straight up, the Look of the windings won't matter.
Yes, the 24Ga wire is a tight fit but it was well described here a couple posts ago; Get the 8 windings in with as much care as possible and jam the last winding in somewhere.
Chico John is offline Find More Posts by Chico John
Reply With Quote
Old Oct 03, 2012, 04:20 PM
wait, there was a tree ?!?
moray's Avatar
Switzerland, ZH, Oberengstringen
Joined Jun 2012
155 Posts
So just rewound the 2812 with 9turns of 24ga gobrushless newbie wire, i know there is a lot room for improvement on the winding job, but as it is my second rewinding I'm quite happy with the results.

Benched it on APC 7x6 3s 45-90C peaks at 28.7 amps and 329watts. Doesn't get really hot at all.

Just wanted to say thanks a lot for the hints and tips for rewinding.
moray is offline Find More Posts by moray
Reply With Quote
Old Oct 03, 2012, 04:57 PM
Planes in flames,,,
jetpackninja's Avatar
Gravity Sucks
Joined Aug 2010
3,564 Posts
Awesome- if it doesn't smoke on the bench you've probably done it right.

Mine do get quite hot but I suspect that the MD hi temp rated wire is what makes this such a successful option. Get out there and feel the difference.

Hey- you guys that run the rewinds, some have said the their motors do get quite hot. Do you do a cool down between flights or do you just go for it?
jetpackninja is offline Find More Posts by jetpackninja
Reply With Quote
Old Oct 03, 2012, 05:42 PM
Registered User
Joined Jun 2011
123 Posts
Quote:
Originally Posted by jetpackninja View Post
Awesome- if it doesn't smoke on the bench you've probably done it right.

Mine do get quite hot but I suspect that the MD hi temp rated wire is what makes this such a successful option. Get out there and feel the difference.

Hey- you guys that run the rewinds, some have said the their motors do get quite hot. Do you do a cool down between flights or do you just go for it?
I keep an extra motor already rewound with a prop saver and prop on it just in case I burn up the motor. I don't think about resting the motor, I figure they're cheap enough not to worry about it.
Whomprat is offline Find More Posts by Whomprat
Reply With Quote
Old Oct 03, 2012, 06:09 PM
Registered User
Joined Jun 2009
391 Posts
Hooked

Quote:
Originally Posted by moray View Post
So just rewound the 2812 with 9turns of 24ga gobrushless newbie wire, i know there is a lot room for improvement on the winding job, but as it is my second rewinding I'm quite happy with the results.

Benched it on APC 7x6 3s 45-90C peaks at 28.7 amps and 329watts. Doesn't get really hot at all.

Just wanted to say thanks a lot for the hints and tips for rewinding.
OK: He's hooked. That looks sweet, I used just the red spool. Very colorful and wound nicely, hope it screams.
I ran 3 batteries on a rewound motor and never turn off the transmitter, just change out the batery and went on and the motor warmed up but never felt that it was over heating. On a 30a ESC.
Nice work.
Chico John is offline Find More Posts by Chico John
Reply With Quote
Old Oct 03, 2012, 07:38 PM
Registered User
Left Coast DJ's Avatar
United States, CA, Los Angeles
Joined Jan 2012
1,068 Posts
I know reflective tape is the recommended method of decorating these wings. Anyone try spray paint? If so, which ones stick? Krylon Fusion?
Left Coast DJ is offline Find More Posts by Left Coast DJ
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
WALLY WING...no fins...flies great!!! gpw Foamies (Kits) 22 Sep 23, 2009 06:56 AM
Qjet Flamingo & Butterfly: A plane no one has!! romans1015 Parkflyers 6 Jan 29, 2004 04:05 PM
Qjet Flamingo & Butterfly: A plane no one has!! romans1015 Parkflyers 0 Jan 28, 2004 12:40 AM
Noob concept plane Mikey C. Foamies (Kits) 5 Nov 11, 2003 01:05 PM
It's a boat...It's a plane...no! It's flightship! MrBungle Electric Plane Talk 24 Jun 26, 2001 01:55 AM