oil in the motor

I have (ahem) a friend (ahem) who was a little careless with a can of WD40
on the motor of a Hornby HST. Under DC, it would run fitfully, but after
removing the body it became obvious that arcing was going on around the
armature. I have tried to clean the comutator and carbon brushes with
spirit, but is seems to make no difference. I was so confident that the
cleaning would fix the problem that I installed a Lenz Gold
decoder....but.... it's just as bad as ever
two questions :
1. Have I - ahem sorry - has my friend wrecked the motor beyond repair or is
there something to be done?
2. How do you get the thing apart? - there are two clips which partly
release the plate at the top of the motor, but I can't see how to release
the bottom part so I can remover the armature and thoroughly clean it.
Adrian
Reply to
AdrianB
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In message , AdrianB writes
Treat yourself to a can of what used to be sold as TV tuner cleaner. Spray liberally around the comutator. That should dissolve all the old oil, gunk, WD40 etc. Allow to dry before testing, because the cleaner is highly flammable. For truly spectacular results, apply power with the motor covered in cleaner. How do I know? A friend told me ...
:-)
Reply to
Graeme
Don't ever try it with a hand-held food mixer and don't ask me how I know that :o(
(kim)
Reply to
kim
White spirit is itself oily. I always used meths to clean commutators and brushes. That may not be the problem though.
(kim)
Reply to
kim
You've got oil where it shouldn't be! No you haven't irrepairably destroyed your motor (yet) - the commutator has oil on it and needs cleaning. - the brushes are stuffed and will have to be replaced. If you replace the brushes the oil on the commutator will saturate the new brushes, so that probably won't totally fix it. You need to get the brush plate off and clean the excess oil off the commutator etc and then replace the brushes.
Greg.P.
Reply to
Greg Procter
1. The Ringfield drive can be repaired, Hornby Service Sheet 205c, has a list of any parts that may be needed. 2. Before starting to dismantle the drive unit, make sure you have a sheet of white paper A3/A4 on the bench or table where you are going to work. Watch out for the hair springs that keep the brushes in place. They have a habit of jumping out if you are not careful when releasing the pressure plate. Release the two clips holding the plate at the top of the motor. Then using a thin blade, gently prise the plate away from the motor. Clean the armature with Meth's or Lighter fuel using a lint free cloth. Also, clean any grunge that might be lurking inside the motor housing, and plate. 3. When reassembling, add a drop of oil to the bearings where the spindles of the armature pass through. I would also consider replacing the brushes with new ones, and maybe the springs. 4. Place two wires from the transformer unto the drive unit contacts, turn the power on. This will make sure that everything is in working order before you place the drive unit back into the HST. If it still spins slowly, then bend the two spring contacts to apply more pressure to the springs holding the brushes to the armature, and test again. This is a old trick to make the ringfield drive unit spin faster.
HTH's
Wilson
Reply to
Wilson.R.Adams
Apart from having a go at repairing model trains I also like to help people with PC problems. My near neighbour had recently retired and had bought an old PC off his company with his retirement 'lump sum'. I don't know the cost of this PC but it must be about 5 to 6 years old and when he 'lost his sound' he asked me to take a look.
I took the side panel off, luckily in the shed, and was greeted by a cloud of dust. Why do companies keep 'desktop' PC's on the floor ? I normally give the inside a blast over with a can of compressed air but this called for the industrial cleaner.
"OK" I though "he said the sound had packed up so try and fix that". I removed the sound card which was still coated in dust and something resembling a grey version of blue tack. My guess is it was a combination of dust, moisture and human skin.
How to clean it without damaging the circuits ? I then remembered the 'sonic bath' we had, only a cheap one ... less than =A320. A check of the instructions confirmed it was suitable for cleaning PC parts so I gave it a go. It was only a small 'cut down' card so it fitted in the bath bowl.
About 45 minutes later the clean AND DRY card was back in the PC and working.
I have also tried it on a motor from a loco that my son had been given. It looked like it had been 'oiled' with axle grease and took several 'baths' to get it clean. If I can get away with this method without fully dismantling the motor on a 'dead' loco I will try it in future.
Reply to
Dragon Heart
Well, speaking as an IT manager and reluctantly allowing many PCs to reside on the floor, I can answer that. People like to have as much desk space as possible on which to work. Actually, in my experience, PCs on the floor don't get that much dustier inside than those on desks. The fact is that most work environments are just grubbier than our homes where we tend to vacuum more thoroughly and regularly.
In these devices, where does the filth end up? dous it just fall to the bottom?
Adrian
Reply to
Adrian
One of the other problems in an office is the device that circulates pollens and dust, otherwise known as the air-conditioning unit. You will see a marked more fine dust etc in that envoirament than from a machine in a home or conventionally ventilated area.
Reply to
estarriol
I hope they didn't take *all* of his lump sum back for this dinosaur, they should have given it to him for saving the trouble of disposal of it.
Kevin Martin
Reply to
Kevin Martin
I have also tried it on a motor from a loco that my son had been given. It looked like it had been 'oiled' with axle grease and took several 'baths' to get it clean. If I can get away with this method without fully dismantling the motor on a 'dead' loco I will try it in future.
Dragon Heart, Using the Sonic Bath method may or may not work with the electric motors, I do not know nor am I about to find out.
But, what I do know is, by stripping down the drive unit also gives you the chance to inspect the drive unit for any sign of wear and tear.
Wilson
Reply to
Wilson.R.Adams
Companies are weird. They normally demand "book value" for old PCs which way above what they're actually worth. They usually end up either gatheing dust in a storeroom or thrown in a skip.
(kim)
Reply to
kim
What a con and dispicable thing to do making a profit out of a retiring employee, PCs along with other hardware will have been written off against tax over 3 years so effectively it cost them nothing.
See my comment above.
Alan
Reply to
Alan P Dawes
Youre not allowed to do that these days, so the store room option is favourite. There must be zillions of PCs lying idle like that.
Adrian
Reply to
AdrianB
The one we have is a simple stainless steel bowl into which you put water and a spot of washing up liquid. All the dirt drops to the bottom of the bowl.
On the subject of companies keeping 'desktop' PC's on the floor I agree with all your points the main problem is cleaners in my old company NEVER cleaned under the desks.
I asked him Kevin and thankfully no ! they didn't take all of his lump sum back but it was a couple of hundred pounds.
Again I agree with Wilson's comments but most of my son's 'donated' loco's simply needed a good clean.
Reply to
Dragon Heart
I have bought new brushes and springs, and this time managed to get the plate off the side of the motor. I couldn't seem to budge the spur gear to allow the whole armature to be removed, so I cleaned all the commutator, back of the plate and brush recesses using track cleaner. Plenty of gunk was removed.
Sadly, on re-assembly, with new brushes, there was no difference and I still get white flashes of arcing visible around the comutator - although oddly, it seems not necessarily where the brushes are making contact. I'm concerned now that some of the insulation on the windings may be damaged.
I'll try doing this again and be a little more persistant with the spur gear, and pay special attention to the insulated areas between the segments of the comutator - I wonder whether that is where I am seeing the arcing.
Adrian
Reply to
AdrianB
It sounds like you have conductive gunk in the slots between the commutator segments. That's not a disaster.
You'll need to take the brush plate off the motor and _carefully- scrape between the commutator segments. (needle)
The gear on the back of the armature is pressed on to the shaft. It's really not a good idea to take it off as it could well become loose and slip.
Greg.P.
Reply to
Greg Procter
"AdrianB" wrote
Not difficult. Have removed hundreds (literally) in the twenty years we've been trading.
You need to support the motor housing (I use a small vice with the jaws apart wide enough to allow the armature to pass between them) and tap away at the armature shaft with a small hammer and a short piece of metal rod of a slightly smaller diameter than the motor shaft.
John.
Reply to
John Turner
At at 12 volts I would be suprised if the winding insulation had broken down, but it could well have been damaged during attempts at dis-assembly/cleaning. Giving the windings a good coat of varnish should solve the problem, if that is what it is. Varnish is the traditional material, but at 12 volts pretty well any coating will do, paint, nail varnish etc. Pay most attention to the outsides of the coils as that's where the damage will have occurred.
Gordon
Reply to
gbubb

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