Delighted with my 3 new Altaya toys (Say, Mr M, weren't you and Scott getting some of these? Oh, not arrived yet, eh?) and prompted by a thread about running in motors I thought I would do some highly scientific experiments with the RX cans.
I took out the bushes and had a look-see at the state of the curved edges; where they contact the commutator and where the business of getting revs starts.
First thing to note was that in each case the slot where the retaining spring sits at the backend was cut at 90 degrees to the way it should have been, i.e. the curve of the bush was set at 90 degrees to the commutator plates, so only the very corner tips would have made any sort of contact at all.
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The finish of all the bushes was a clearly a little dull, not having been used.
So, I wired them up to a piece of track with crocodile clips, filled an up turned SCX crystal case with an inch or so of H2O and set my stopwatch for 45 seconds. I then gave it a little voltage.
Once the time was up, I took out the bushes again and had another look-see. It was very clear that the top and bottom edges had been buffed up. Presumably these were the only parts in genuine contact with the commutator.
Intrigued, I re-assembled the motor and submerged it again but let it have a full minute.
This time the shiney buffed area had expanded across the face of the bush nicely.
Will this make a difference? I may get to see on Tuesday night but what with our rebuild plans we may not actually have proper running. Sorry, that makes this experiment a bit open ended but I thought I would share my results so far - running under water appears to bed the bushes quickly.
I guess I should try and do a control experiment with a minutes worth of running on a fresh motor in fresh Oxfordshire air. I'll try and find time today.
Note: At the end of the second stint I thought I would give it full bananas, right at the end of the time - man, it's impressive how much spray a little spinning armature can shift, isn't it?
![Image]()
D'oh!
FOR KIDS AND THE LITIGIOUS AMONGST YOU
SF does not recommend the mixing of electrics and water. It is stupid - especially the full chat burst at the end, you will get wet!
[Edited for some bits to actually make sense]
I took out the bushes and had a look-see at the state of the curved edges; where they contact the commutator and where the business of getting revs starts.
First thing to note was that in each case the slot where the retaining spring sits at the backend was cut at 90 degrees to the way it should have been, i.e. the curve of the bush was set at 90 degrees to the commutator plates, so only the very corner tips would have made any sort of contact at all.
The finish of all the bushes was a clearly a little dull, not having been used.
So, I wired them up to a piece of track with crocodile clips, filled an up turned SCX crystal case with an inch or so of H2O and set my stopwatch for 45 seconds. I then gave it a little voltage.
Once the time was up, I took out the bushes again and had another look-see. It was very clear that the top and bottom edges had been buffed up. Presumably these were the only parts in genuine contact with the commutator.
Intrigued, I re-assembled the motor and submerged it again but let it have a full minute.
This time the shiney buffed area had expanded across the face of the bush nicely.
Will this make a difference? I may get to see on Tuesday night but what with our rebuild plans we may not actually have proper running. Sorry, that makes this experiment a bit open ended but I thought I would share my results so far - running under water appears to bed the bushes quickly.
I guess I should try and do a control experiment with a minutes worth of running on a fresh motor in fresh Oxfordshire air. I'll try and find time today.
Note: At the end of the second stint I thought I would give it full bananas, right at the end of the time - man, it's impressive how much spray a little spinning armature can shift, isn't it?
FOR KIDS AND THE LITIGIOUS AMONGST YOU
SF does not recommend the mixing of electrics and water. It is stupid - especially the full chat burst at the end, you will get wet!
[Edited for some bits to actually make sense]
