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[Nordsee]

I want to run-in a new 385 Motor, I seem to recall that it is possible to suspend the Motor in water and run it, this beds the brushes in better, is this true? Does one use a low voltage or the usual power supply? Doesn't it short out the battery? Lower it in the water running or first in and then start? I await your answers...

[TailUK]

I was wondering the same thing so I looked on U-Bend, (sorry Youtube) and found this video.
 
http://www.youtube.com/watch?v=mD3nWxmgX70

[malcolmfrary]

Important point - DISTILLED WATER.
The guy has heard rumours but seems to know little about motors as such.  The "crud that was in the motor" is the remnant of the brushes that was removed by the bedding in process.  The cleaning that he mentions need only happen in the brush/commutator area.  Using car type contact cleaner, which is basically isopropyl alcohol, the muck and water residues should be dislodged, but any hint of dampness must be allowed to dry off before the motor is run again.  The motor bearings do need to be lubricated - the dunk in water will have removed any trace of oil.

[More Coffee]

I wouldn't put in water..
I use "Brake Parts Cleaner" to clean just about everything electrical,
In saying that.. I don't use it on PCB's , the chemical mixture in the parts cleaner can reduce some types of PCB's to dust..and it will remove any lubricant from the bushing's , a little SAE20(detergentless) or 3in1 oil generally fixes that.
 
Now. your motor if its just going one direction ,,it will bed itself ,lightly loaded.. If its for something that well be going either direction at anytime.. the brushes will bed in better one way..often some slightly almost unnoticeable performance is lost going opposite..
 
 

[Nordsee]

The Motor is planned to be in my Glynn Guest Submarine, virtually always in the same direction, and lightly loaded. I just wanted to cut down on the arcing that happens with a new, cheap, brushed Motor.

[grasshopper]

All 'running in' brushed motors achieves is getting the new square ended brushes to conform to the shape of the commutator. Doing it the water way just softens the brushes, keeps it cool and floats the worn bits away, depositing a lot of it all over your motor, it also washes away any lube in the bearings etc...


it was a method used by stock RC car racers where you were given an out of the box 540 motor as part of your entrance fee so no one had an advantage, some people would connect it to a battery pack, drop it in water for a couple of minutes, dry with an airline and install in car and race it -the idea being that the brushes being worn to the comm' shape would allow more current to pass and result in a quicker motor.



If you want to bed your brushes in, connect to a single cell, or two and leave to run slowly until the cell goes flat, blow out the crud and install in your model, similar result.

[Looverlijn]

Tell me... is this idea of running/bedding in brushed motors just required for "gusset-ripping" car motors or is it a general purpose technique that would benefit any brushed motor? Along the lines of say smoother running, longer life, etc.

[malcolmfrary]

The Motor is planned to be in my Glynn Guest Submarine, virtually always in the same direction, and lightly loaded. I just wanted to cut down on the arcing that happens with a new, cheap, brushed Motor.

A lot depends on how cheap the motor is - metal brushed ones will be neutrally affected - there might be a performance improvement, there might equally be a reduction in its life expectancy, and the com/brushes will need a shot of lube.
Bedding in carbon brushes almost certainly helps, the water process probably beds the bearings in nicely as well, but they will need to be lubed before real out in the air use.  When it comes out of the water, there will be a layer of carbon on the bare conductive metal bits and their surrounding insulating bits which does need to be removed, along with any water that it might retain.  The contact cleaner does a good job of flushing the residue away, and also carries away the trapped water.  The insides of the motor does need to be totally dry before use, or else the bedding in will continue with a vengeance, when it stops being bedding in and starts being rapid wear.

[grasshopper]

Tell me... is this idea of running/bedding in brushed motors just required for "gusset-ripping" car motors or is it a general purpose technique that would benefit any brushed motor? Along the lines of say smoother running, longer life, etc.

Suppose it's like anything really, if you're not going to run a new motor right on the ragged edge, then it's probably not that much of an issue. Most model boaters run low / medium speed scale boats and can fit a Mabuchi type can motor and never have an issue as long as it doesn't rust up from lack of use.


The speed hounds used similar motors and essentially abused them in the quest for performance..but now they'd be better off going brushless if they want real get up and go.