DT,
You are correct...reverse the wires to change the motor direction...
Cheers,
Jim
Quadrocopter and Tricopter Info Mega Link Index

Originally Posted by dumb_thumbs

so, I finally got my motors, but all 4 of them have the black and white wires (could have sworn I ordered a set of each kind). To reverse two of the motors, should I just reverse the polarity of the wires, or will that not work? I have a feeling it will work, I just can't remember.

-Heath

I want to build one of these things so bad, For cheaper than 18 bucks you can't go wrong. HOw are peoples builds going who have done this

Originally Posted by dave1993

ahhh... should have heeded that warning about supporting the end when pushing on props. sometimes in a crash too so its a good idea to have a "stop" for the bottom of the motor. if i can find that post ill move it to post #1 because thats how i killed 2 motors too.

so that was why your board was quitting on partial throttle? or was that a fluke?

The 1st motor to go slow was probably damaged when it did a flip and busted an arm before leaving for college, either then or when it accidentally went to full trhottle and drilled the ceiling in the canteen on break time :s

I when the LiPo was running out the first day the problem went away, when the cell was fully charged it came back, here's my theory...

I didn't want the trim back the wires I soldered on so I sort of coiled each of them up (once around my little finger), I'm thinking that on low throttle these little coils were producing an E M pulse at the rite frequency to confuse the FC.

So that coupled with not having a the other wire next to the pulsed wire to help cancel it out (I think this is what you were talking about with the "oddball" wiring).

If I'm lucky Monday night will bring a full rebuild with two new motors and new frame, I have some new frame ideas, partly from the bending experiments I've show/email chats with a friend and a few novelty frames, I think I would have to build those before talking about them though

I bought v939 pcb board but cannot bind it to either WL or Flysky Tx. What is the correct way to bind them?

I have another quick question as I get ready to put my quad together. I'm using walkera props, and the top of the center hole is solid (i.e. the center hole does not go all the way through). Do I just push through this, or should I try to first make a whole with a .020 piece of music wire, then push them on? I have a feeling I'd want to make a hole in the prop so I don't break the motor trying get the props on the shafts of the motors. Also have a whole will help me center the props so I don't have a lot of vibration.

-Heath

Originally Posted by turnberry

I bought v939 pcb board but cannot bind it to either WL or Flysky Tx. What is the correct way to bind them?

Try this for original V929/V939 Tx...
http://www.rcgroups.com/forums/showp...postcount=2091

Worked for me.

Nigel.

Bangood now has strong Ladybird spare motors CW & CCW for $2.89 : http://www.banggood.com/Wholesale-7m...r-p-51897.html

They will definitely lift my DIY quad (26g) where the Aliexpress 7mm motors lost.

Gents,
Has anyone found the 7mm x 20mm w/1mm shaft motors anywhere in bulk for a decent price?
7mm Hollow Cup Motor:
Description:
Motor Diameter: 7mm
Motor Length: 20mm
Shaft Diameter: 1.0mm
Cable Length: 60mm
Rotating Speed: Over 50000

It seems to me the best deal is to get the UDI U816 arms that have those motors in them and then you get spare parts for $3.20/ea: http://www.banggood.com/Wholesale-Ud...4-p-48836.html

The 716 motors we bought in bulk are now $13.46 for 20x shipped so .67 cents/ea : http://us.aliexpress.com/snapshot/20...Redirect=false

Cheers,
Jim
Quadrocopter and Tricopter Info Mega Link Index

Originally Posted by mystman

Bangood now has strong Ladybird spare motors CW & CCW for $2.89 : http://www.banggood.com/Wholesale-7m...r-p-51897.html

They will definitely lift my DIY quad (26g) where the Aliexpress 7mm motors lost.

Sure, but I needed only the motors to repair my LB/v939 hybrid and rebuilding a v939 from spares. I hope they are real LB motors as they are the strongest.
I also ordered the UDI motorarms (still waiting for them)

Originally Posted by dumb_thumbs

I'm using walkera props, and the top of the center hole is solid (i.e. the center hole does not go all the way through). Do I just push through this, or should I try to first make a whole

i didnt bother making a hole but just pushed the shaft through. the plastic is very thin there on walkera props and easy to do this.

udi which are the lowest cost option have a hole all the way through but its very small at the top and needs to be drilled out first. i find it best to make the hole undersize so its a REAL tight fit. these have a reputation for flying off so need all the help they can get. ive yet to recover any of the black ones that went shooting off. luckily the orange are easier to see in the grass.

one advantage to the s107 motor is very long shaft. this leaves some poking through for glue or galling.

Originally Posted by dumb_thumbs

I don't break the motor trying get the props on the shafts of the motors. Also have a whole will help me center the props so I don't have a lot of vibration.

pushing too hard w/o supporting the bottom is almost guaranteed to pop the end off. usually not fixable. so always push against a table top or if its in the holder use a bamboo stick againt the end being careful not to touch the wires. i find a few pu foam bumps at the bottom of the holder tube will help prevent the end popping off in a crash. maybe a tiny bit of ca around the cap edge before inserting the motor will help too. ive lost more motors to this kind of damage than simple wear.

Originally Posted by mystman

They will definitely lift my DIY quad (26g) where the Aliexpress 7mm motors lost.

are you saying your dquad will not lift with ali motors? i found they were very strong and saw no difference compared to s107 motors. i didnt actually try lb motors on my diy but in an altitude contest with a buddy mine beat the crap out of his ladybird. this is with udi props too. maybe because the lb weighs more? and my diy octo is even hotter. it shoots up like a rocket.

Originally Posted by dave1993

are you saying your dquad will not lift with ali motors?

Yes, mine don't produce enough thrust :-( Not compareable with the LB ones. They are "rockets" with much lifting power.
Should the ali motors lift a LB like its own motors? It looks like the ali motors also havn't enough rpm.

from what others say it looks like mike guo is sending out at least five different types of motors: .8mm shaft with with long thin red/blue wires, .8mm shaft with short thick red/blue wires, .8mm shaft short thick with white/black wires, 1mm shaft with short thick red/blue wires, and 1mm shaft with long thin white/black wires. ive only got one type with .8mm shaft and they seem to have same thrust and rpms as s107 motors. i wonder if the specs vary too. what kind of aliexpress motors do you have?

has anybody else tried these yet?

Originally Posted by dave1993

from what others say it looks like mike guo is sending out at least four different types of motors: .8mm shaft with red/blue wires, .8mm shaft with white/black wires, 1mm shaft with with red/blue wires, and 1mm shaft with white/black wires. ive only got one type with .8mm shaft and they seem to have same thurst and rpms as s107 motors. i wonder if the specs vary too. what kind of aliexpress motors do you have?

has anybody else tried these yet?

I have the motors with 0.7mm and 1mm shaft and red/blue wires.
Can't use them as replacement motors for my LB/v939 hybrid. The barely lift the quad (22g without battery) :-(

Do s107 main motors have enough thrust to be used on a stock v939 as replacements?

i dont have a v939 but my s107 and .7mm ali motors have more than enough lifting pwoer for my diy even with camera. it even beats my friends lb. 23 grams with 138mah battery for the 30cm one and 28 grams for the 60cm. a 600mah battery only adds about 10 gram so it dont look like weight is the problem. maybe this aliexpress dealer is not a reliable source although 2 guys who dont post here had no trouble lifting with them. and at least 3 guys are using the s107 motors from focalprice w/o problems. dj also said his lifted ok but i forgot what type of motors.

maybe its good i didnt change the parts list in post #1 because those motors are known to be ok. there are at least a dozen sources for 7mm motors so maybe its time to compile a list and keep track of what works. my 1mm ali motors should be arriving shortly so that will be interesting.