Dual brushed motor break in jig
 

EDIT: So after much discussion and debate the water break-in method looks good and there's a lot of internet hype but it probably shouldn't be done. I also didn't realize the magnetic fields in that proximity could cause issues.

So, don't do what I did here kids :)

So I have two new motors to break in. They are stock Axial 27t motors I'm giving a whirl in the XR10 (I want to see how the increased wheel speed is with these on 2S). If I don't like them I'll go back to the 35t on 3S.

Setup:
http://i202.photobucket.com/albums/a...C/DSC_0738.jpg

I have two plastic cups stacked together to make a lip at the top. The wires are bent over the edge and held in place with a rubber band.

http://i202.photobucket.com/albums/a...C/DSC_0736.jpg

The two motors are rubber banded together to keep them secure when I turn them on.
http://i202.photobucket.com/albums/a...C/DSC_0741.jpg

http://i202.photobucket.com/albums/a...C/DSC_0739.jpg

Lastly the battery. This is a pretty nice battery I used a few years back but now it's been retired to motor break in duty. The best part is that since it's laid out like this and no shrink wrap on the outside you can tap 3 cells at a time.

http://i202.photobucket.com/albums/a...C/DSC_0743.jpg

You can see that I have white and green for + and - (respectively).

1. You connect the first white to the positive lead out of the pack.
2. First green connects to pack - out
3. Second white and green connect to the bar between the 3rd and 4th cells.

When you hook it up each motor gets a green and white, just connect the leads from the pack +/- to separate motors. Then connect the opposing wire from the center of the pack. The motors will spin to live with half of the pack voltage.

The pack is charging now so I'll hook it up shortly and get a few more pictures

Re: Dual brushed motor break in jig
 

Note, in that last picture there are 4 separate leads, they don't loop back around off the picture. I'll take some pictures of it all hooked up shortly.

For water I'm just using clean bottled water. The stuff from the tap has too much chlorine and all that other stuff so I prefer not to use that. Some people say you need ionized fancy water, but I've used bottled water many times and it's worked fine.

Re: Dual brushed motor break in jig
 

What 35t motors were you running?

Re: Dual brushed motor break in jig
 

I don't have them yet, but plan to run the Holmes TorqueMaster Expert or Sport. I just got the XR so haven't actually put any motors in it yet.

I guess my wording should have been "go back to the tried and true motor choice" :)

Re: Dual brushed motor break in jig
 

You realize that having them that close together while running can weaken the magnets right? As they generate field from the armature, it will alter the magnetic field of the magnet.

Water break in in entirely unneeded. At best it just saves you some time if you manage to do it correctly. Most of the time, it's done incorrectly and the the brushes end up messed up, along with the comm.....and rarely does the motor get cleaned out correctly, so rust will show up.

Save yourself the headache, break them in at about 5 volts for 10 minutes or so on the bench.....with a fan blowing on them.

Later EddieO

Re: Dual brushed motor break in jig
 

You might be better off breaking those in dunked in the toilet, and flush em when done...

Just kidding, but I don't think you'll be happy with them. I have one, so I dyno'd it and compared it to a Br00d HHK 35 turn, at 8.4 volts.

http://i583.photobucket.com/albums/s...5Axial27PE.jpg

The HHK 35T makes pretty as much power as the axial, and pulls 17 less amps doing it. That's huge. The HHK also hasnt even peaked, since the dyno wont measure that much torque. Check out how much more efficient the HHK is, too. It's not on this graph but the HHK makes from 6 oz-in to 16 oz-in of torque all within 2200 rpm. The axial spans 6000 rpm in that torque range. The HHK will have a whole lot more snap and generate wheel speed much quicker. Run the HHK on 3s and it'll murder that axial motor.

Also in regards to wheel speed, it's only about 3600 rpm at the 6 oz-in torque step. With no load the HHK spins 12300 on 2s and 20300 on 3s. The axial spins 17400 on 2s. I'd guess the axial would have to run smaller pinions to survive and the final wheelspeed product probably wouldnt be much more than the HHK 35t run on 2s.

Re: Dual brushed motor break in jig
 

Excellent chart. It's scary to see how much amperage those motors pull at that RPM! I definitely will stick with the 35t on 3S, but you've peaked my interest on the Br00d's. I figure I owe it to myself to at least run these and see how they perform. I got them for almost free ($5 each). They might be great for driving around the yard with my son (he has an AX10 and likes to play follow the leader).

Re: Dual brushed motor break in jig
 

You definitely have a good point there. I never even thought about the fact that sitting the next to each other like that could weaken the magnets.

When I get some good motors I'll go with your suggestion on breaking them in like that. I had actually done it that way years ago when I raced in the early 90's and I always broke in the motors on lower voltage with a fan. I just figured I'd see a ton of hype about the water break in that I'd give it a whirl with some cheap motors.

Re: Dual brushed motor break in jig
 

My motors already come broken in:)

I must ask though, where do you see all this hype on water break in? I know on this forum its typically shot down when mentioned......I know there are some youtube videos of people doing it, but the big problem is, what works for one motor in water break in, rarely works for another. Brush compound/type is the main factor in how long and how much voltage, and very few motors use the same brushes. Many of the chinese made motors, often have different brushes from batch to batch, making water break in even more of a headache.

Stick to your racing experience........lower voltage with a fan.

Have the motors already been ran though? If so, break in is pointless now.

Later EddieO

Re: Dual brushed motor break in jig
 

@EddieO

I have been seeing it on the Traxxas forum a ton, it's like a disease ho much it's spreading. Also on URC too. Which is weird because knowing what I know now, I would suspect that Jang would set folks right.

So, I looked at your motors last night and it was overwhelming because there are so many basic motor types and then each one can come in any number of wind styles. I basically want a 35t motor I can run on 2S or 3S for occasional competitions and fun crawling with my son. So, the high dollar 2 packs I think is a bit overkill for me. Is there a nice quality motor that I can do in the $40ish per motor range?

I may find I really like crawling and want to compete more 8)

Thanks again.

Re: Dual brushed motor break in jig
 

Water break-in is cyclic....someone finds an old reference to it and thinks, "Nobody I know does this, it's a forgotten art, I'll do it and get an edge..." and the motor killing begins.
The idea spreads fast until people find they're killing perfectly good motors, or, that is does not help.
It dies off until the cycle begins again.

As to new motors, I find that if you don't know for sure what you want, you can email Br00d or Holmes and ask. Tell them the following:
-What rig
-Do you comp or run for fun
-What battery (NiMH/NiCD, LiPO...& how many cells)
-What motors you currently have and like/dislike about them

Then they can make suggestions on what to get and can sell matched MOA sets if that is what you need.

Re: Dual brushed motor break in jig
 

Thanks a ton guys. I'm going to run these 27t motors (that I probably wrecked :D ) first and then see how long they last. Then email those guys and see what I need. I haven't talked to anyone from Holmes, but so far EddieO from Br00d has been very helpful. Just based on the customer service so far I wouldn't have any issue buying from him. "thumbsup"