Hi all,
Just thought I'd share this with you. A week or so ago my Graham Farish class 47 'Hadrian' loco failed, it ran a circuit of the track then suddenly slowed down & stopped, the lights still worked but it wouldn't run. So I stripped it down, tested the motor & it would barely turn, luckily I had a spare secondhand motor, put that in & the 47 is back up & running...
Out of curiosity i had a go stripping down the faulty motor, managed to remove the flywheels with a puller, then opened up the casing & lots of bits of solder fell out. I found that a disc/ring had become detatched from the armature which has obviously caused the failure. Also noticed the commutator has quite a bit of wear, the brushes didn't seem all that worn, this is from a loco that I bought 3-4 years ago & has done about 20-30 hours running max on a 4x2 layout...
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/026_zps702332b4.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/026_zps702332b4.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/025_zps13d5607c.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/025_zps13d5607c.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/024_zps690a9659.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/024_zps690a9659.jpg.html)
All a bit worrying really, I'm wondering if this is going to become a common problem as locos start racking up the hours or whether its just a one off....
cheers, Stu.
Hi Stu,
Out of interest can you measure pad to pad on the ring thats detached on the Ohms range please? If Iv got this right its a suppresser and the motor will run fine without it but lord knows why the comm is that worn.
The solder splats are from the joints holding the ring to the armature melting due to heating - possibly from clogged comm segments or maybe a faulty suppresser ring.
Might be worth measuring pad to pad on the commutator to see if the windings have survived.
Regards
Russ
I have remotored a few (Poole) Farish locos in the past with small Japanese (usually Hanazono) 5-pole motors which wasn't too difficult and should be easier with the Chinese built locos where the motor isn't built into the chassis. That commutator wear is shocking - looks like either very hard brushes, or brush springs far too strong. Wonder how long the coreless can motors in latest Farish steam locos will last?
When I queried motor lifetime with my Dapol Panniers I was told by Dapol that the sealed motor can be easily replaced when the wear about, if I remember correctly they expect a lifetime of about 100 hours per motor which doesn't seem a lot to me. :worried:
Quote from: Caz on November 08, 2014, 10:18:47 AM
if I remember correctly they expect a lifetime of about 100 hours per motor which doesn't seem a lot to me. :worried:
Me too! That's outrageous !! :goggleeyes:
Quote from: PostModN66 on November 08, 2014, 10:33:05 AM
Quote from: Caz on November 08, 2014, 10:18:47 AM
if I remember correctly they expect a lifetime of about 100 hours per motor which doesn't seem a lot to me. :worried:
Me too! That's outrageous !! :goggleeyes:
Especially as they have to be run in for 10 hours or so :doh:
OK,OK, I've been told a million times not to exaggerate :sorrysign:
Touch wood all my locos are running fine....I know nothing about these motors but I guess there is a cost v longetivity trade off as with everything we buy...how much we are prepared to pay for a loco ultimately will dictate the quality of all the parts..as an example if grafar could engineer out split gears I would happily pay a bit more
Quote from: RussellH on November 07, 2014, 09:53:29 PM
Hi Stu,
Out of interest can you measure pad to pad on the ring thats detached on the Ohms range please? If Iv got this right its a suppresser and the motor will run fine without it but lord knows why the comm is that worn.
The solder splats are from the joints holding the ring to the armature melting due to heating - possibly from clogged comm segments or maybe a faulty suppresser ring.
Might be worth measuring pad to pad on the commutator to see if the windings have survived.
Regards
Russ
Hi,
I put a meter across the pads as you asked but it wouldn't give a reading :hmmm:. I could see a couple of the winding wires have broken as well, probably as a result of bits of solder flying around & the ring detatching itself, its far to small a motor to even attempt to try & re-solder it so I've binned it. Looks as if the only answer with these locos is to replace the motor once they've failed.
cheers, Stu
Hi Stu ... great topic you've raised, sorry to hear of the circumstances though.
Quote from: belstone on November 08, 2014, 09:28:38 AM
I have remotored a few (Poole) Farish locos in the past with small Japanese (usually Hanazono) 5-pole motors which wasn't too difficult and should be easier with the Chinese built locos where the motor isn't built into the chassis. That commutator wear is shocking - looks like either very hard brushes, or brush springs far too strong. Wonder how long the coreless can motors in latest Farish steam locos will last?
Belstone - not wishing to hijack this thread but could you either post details about your re-motoring of Poole Farish with Hanazono motors here, or PM me. I'm very interested to learn more and posed this question a few months back.
Dan
Quote from: Caz on November 08, 2014, 10:18:47 AM
When I queried motor lifetime with my Dapol Panniers I was told by Dapol that the sealed motor can be easily replaced when the wear about, if I remember correctly they expect a lifetime of about 100 hours per motor which doesn't seem a lot to me. :worried:
That's funny Caz, really funny ;D "Easily replaced". That's fine, so long as the motors are still manufactured. Let's see if we can get replacements down the line.
Poole Farish motors are easy to replace too, but for how long they'll be available, I'm not sure (they aren't used in the current Bachman products and so it's surely only a matter of time before Bachmann stop supplying them). Fortunately though, the Poole motors are built like a tank and if well maintained, shouldn't burn out or fall to pieces (just my opinion).
As for the 100hrs, I believe Bachmann Farish are the same. Sounds great value for money doesn't it?
Cheers
Dan
Quote from: DesertHound on November 08, 2014, 04:03:54 PM
Belstone - not wishing to hijack this thread but could you either post details about your re-motoring of Poole Farish with Hanazono motors here, or PM me. I'm very interested to learn more and posed this question a few months back.
Dan
;)
A new thread would be great and would save hijacking this one.
Quote from: mk1gtstu on November 07, 2014, 08:07:22 PM
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/026_zps702332b4.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/026_zps702332b4.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/025_zps13d5607c.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/025_zps13d5607c.jpg.html)
I agree. What's strange is that the brushes still have plenty of meat on them - if you've done 30 hours then the brush wear looks relatively small, but the commutator wear looks excessive - the deep groove in it just shouldn't happen in that period of running. It's almost like the brushes are harder than the commutator.
If so the first failure point of these motors will be the commutator rather than the brushes. There isn't so much you could do in either case, unless spare components are made available (not likely) - it's a replacement motor. However, most of these are the same dimensions as the Mashima 1015, so this could be substituted (it's a better motor anyway, as it's 5 pole; but has the disadvantage of having larger diameter shafts meaning flywheels need their central hole opened out).
The ring that became detached seems to serve no great purpose - I've seen this on several locos, it's common on early Union Mills steam locos which use a very similar type of motor. The rings do cause all sorts of damage if they become detached, but this usually only happens if the motor gets very hot, enough that the solder softens as others have said. I think ultrasonic cleaning may be an option to clean can motors and their commutators without having to disassemble them, but have yet to try this.
I would contact Bachmann and make them aware of your findings, and see what they say - 30 hours really isn't enough IMHO (that's £2 an hour if the loco cost you £60......).
Cheers,
Alan
Quote from: Caz on November 08, 2014, 04:19:34 PM
Quote from: DesertHound on November 08, 2014, 04:03:54 PM
Belstone - not wishing to hijack this thread but could you either post details about your re-motoring of Poole Farish with Hanazono motors here, or PM me. I'm very interested to learn more and posed this question a few months back.
Dan
;)
A new thread would be great and would save hijacking this one.
It's ok Caz - found Belstone's blog ;)
Quote from: DesertHound on November 08, 2014, 06:21:30 PM
It's ok Caz - found Belstone's blog ;)
A link would save others looking. ;) :-*
Quote from: Caz on November 08, 2014, 06:26:15 PM
Quote from: DesertHound on November 08, 2014, 06:21:30 PM
It's ok Caz - found Belstone's blog ;)
A link would save others looking. ;) :-*
Wouldn't want to hijack the thread Caz :) oh go on then ... here you are ...
http://belstone9mm.blogspot.ae (http://belstone9mm.blogspot.ae)
I don't think it goes into detail about the Hanazono motors but I'll encourage Belstone to get a thread going and we'll rightly keep this one for what its title implies it's about.
Cheers
Quote from: mk1gtstu on November 07, 2014, 08:07:22 PM
Hi all,
Just thought I'd share this with you. A week or so ago my Graham Farish class 47 'Hadrian' loco failed, it ran a circuit of the track then suddenly slowed down & stopped, the lights still worked but it wouldn't run. So I stripped it down, tested the motor & it would barely turn, luckily I had a spare secondhand motor, put that in & the 47 is back up & running...
Out of curiosity i had a go stripping down the faulty motor, managed to remove the flywheels with a puller, then opened up the casing & lots of bits of solder fell out. I found that a disc/ring had become detatched from the armature which has obviously caused the failure. Also noticed the commutator has quite a bit of wear, the brushes didn't seem all that worn, this is from a loco that I bought 3-4 years ago & has done about 20-30 hours running max on a 4x2 layout...
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/026_zps702332b4.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/026_zps702332b4.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/025_zps13d5607c.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/025_zps13d5607c.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/024_zps690a9659.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/024_zps690a9659.jpg.html)
All a bit worrying really, I'm wondering if this is going to become a common problem as locos start racking up the hours or whether its just a one off....
cheers, Stu.
Stu
It looks to me as though the suppressor ring might of detached itself and then "collared" the commutator, wearing it down with each rotation. As Russell said, the motor will still run without this suppressor ring, hence why you might not have noticed the problem earlier. Was there any untoward sound when you ran it, prior to it stopping completely?
Dan
Quote from: Dr Al on November 08, 2014, 05:56:45 PM
Quote from: mk1gtstu on November 07, 2014, 08:07:22 PM
The ring that became detached seems to serve no great purpose - I've seen this on several locos, it's common on early Union Mills steam locos which use a very similar type of motor. The rings do cause all sorts of damage if they become detached, but this usually only happens if the motor gets very hot, enough that the solder softens as others have said. I think ultrasonic cleaning may be an option to clean can motors and their commutators without having to disassemble them, but have yet to try this.
Cheers,
Alan
A bit of reading from the experts....
http://www.precisionmicrodrives.com/tech-blog/2011/06/06/a-short-illustrated-primer-on-brushed-dc-motors (http://www.precisionmicrodrives.com/tech-blog/2011/06/06/a-short-illustrated-primer-on-brushed-dc-motors)
Its in place of "the capacitor" to reduce interference.
Sorry to hear its already binned Stu.
Regards
Russ
Useful to know that essentially it has no real effect on the performance as I've seen in those that have been able to be saved after it has come away and been discarded.
I suspect it's a consequence rather than a cause here, but that's impossible to confirm with these can motors where your visibility is totally restricted until you pull it fully apart.
Cheers
Alan
Quote from: DesertHound on November 08, 2014, 07:48:27 PM
Quote from: mk1gtstu on November 07, 2014, 08:07:22 PM
Hi all,
Just thought I'd share this with you. A week or so ago my Graham Farish class 47 'Hadrian' loco failed, it ran a circuit of the track then suddenly slowed down & stopped, the lights still worked but it wouldn't run. So I stripped it down, tested the motor & it would barely turn, luckily I had a spare secondhand motor, put that in & the 47 is back up & running...
Out of curiosity i had a go stripping down the faulty motor, managed to remove the flywheels with a puller, then opened up the casing & lots of bits of solder fell out. I found that a disc/ring had become detatched from the armature which has obviously caused the failure. Also noticed the commutator has quite a bit of wear, the brushes didn't seem all that worn, this is from a loco that I bought 3-4 years ago & has done about 20-30 hours running max on a 4x2 layout...
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/026_zps702332b4.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/026_zps702332b4.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/025_zps13d5607c.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/025_zps13d5607c.jpg.html)
(http://i733.photobucket.com/albums/ww334/raxmk1/my%20railway/024_zps690a9659.jpg) (http://s733.photobucket.com/user/raxmk1/media/my%20railway/024_zps690a9659.jpg.html)
All a bit worrying really, I'm wondering if this is going to become a common problem as locos start racking up the hours or whether its just a one off....
cheers, Stu.
Stu
It looks to me as though the suppressor ring might of detached itself and then "collared" the commutator, wearing it down with each rotation. As Russell said, the motor will still run without this suppressor ring, hence why you might not have noticed the problem earlier. Was there any untoward sound when you ran it, prior to it stopping completely?
Dan
No, it ran normally with no nasty noises then just slowed down to a stop & that was it, it would no longer move under its own power. It was a good smooth runner prior to this, it just failed with no warning.
I would have thought the supressor ring was still attatched until the last minute as the amount of lumps of solder floating about in the motor casing would have caused bad running/noises or seizing up long before this happened. I'm more inclined to think the commutator wear is down to brushes being too hard or springs too strong :hmmm: but as Al says you can't see whats going on inside these motors until you pull them apart.
cheers, Stu.
Quote from: mk1gtstu on November 08, 2014, 09:55:07 PM
No, it ran normally with no nasty noises then just slowed down to a stop & that was it, it would no longer move under its own power. It was a good smooth runner prior to this, it just failed with no warning.
I would have thought the supressor ring was still attatched until the last minute as the amount of lumps of solder floating about in the motor casing would have caused bad running/noises or seizing up long before this happened. I'm more inclined to think the commutator wear is down to brushes being too hard or springs too strong :hmmm: but as Al says you can't see whats going on inside these motors until you pull them apart.
cheers, Stu.
Seems likely that the failure mode was either the commutator becoming clogged up, semi-shorting and heating up the motor to the point that the ring detached and damaged the windings, killing the motor (Was there brush carbon in the commutator, or any evidence of clogging up of the commutator?); or the ring itself coming off first hand and detaching the wiring to the comm. I would suspect the former, if it ran slow first this is a classic case where the motor will get hot (less back emf generated by the slow running, so the motor will pull more current, and the energy dissipated goes as the square of the current, hence heating can go up a lot for small current increases).
It's perhaps too late, but you should save the motor end cap with it's brushes - it might be a useful spare for other models if/when brushes in them wear down (assuming they don't die in this way first).
I would urge you to contact Bachmann and make them aware also.
Best,
Alan
P.s. it's worth investing in a moving coil ammeter, and wiring this to your layout - this can help spot problems before they become terminal - e.g. in this case it would probably have identified a high current draw from the motor prior to complete failure. Very useful for troubleshooting.
Quote from: Dr Al on November 09, 2014, 01:40:36 PM
Quote from: mk1gtstu on November 08, 2014, 09:55:07 PM
No, it ran normally with no nasty noises then just slowed down to a stop & that was it, it would no longer move under its own power. It was a good smooth runner prior to this, it just failed with no warning.
I would have thought the supressor ring was still attatched until the last minute as the amount of lumps of solder floating about in the motor casing would have caused bad running/noises or seizing up long before this happened. I'm more inclined to think the commutator wear is down to brushes being too hard or springs too strong :hmmm: but as Al says you can't see whats going on inside these motors until you pull them apart.
cheers, Stu.
Seems likely that the failure mode was either the commutator becoming clogged up, semi-shorting and heating up the motor to the point that the ring detached and damaged the windings, killing the motor (Was there brush carbon in the commutator, or any evidence of clogging up of the commutator?); or the ring itself coming off first hand and detaching the wiring to the comm. I would suspect the former, if it ran slow first this is a classic case where the motor will get hot (less back emf generated by the slow running, so the motor will pull more current, and the energy dissipated goes as the square of the current, hence heating can go up a lot for small current increases).
It's perhaps too late, but you should save the motor end cap with it's brushes - it might be a useful spare for other models if/when brushes in them wear down (assuming they don't die in this way first).
I would urge you to contact Bachmann and make them aware also.
Best,
Alan
There was a bit of carbon around the commutator, I did save the end cap & brushes, just binned the bits that were no good.
cheers, Stu.
Thanks to all who have expressed an interest in the Farish motor conversions. Sadly this was around 10 or 12 years ago and I cannot find any photos of the conversions although I thought I had taken some. Basically it involved cutting the top section out of the chassis block above the old motor and replacing it with a brass plate to bridge the gap, which provided enough space for an open frame 5 pole with the shafts going through the bearing blocks from the original Farish motor. The motor itself was free-floating in the chassis, with just a couple of tabs to stop it trying to rotate under load. Ideal for DCC conversion as both motor brushes are insulated from the chassis.
Richard
Sounds much the same as this:
http://www.deas.net/littlewood/ (http://www.deas.net/littlewood/)
Cheers,
Alan
Quote from: belstone on November 10, 2014, 07:51:58 AM
Thanks to all who have expressed an interest in the Farish motor conversions. Sadly this was around 10 or 12 years ago and I cannot find any photos of the conversions although I thought I had taken some. Basically it involved cutting the top section out of the chassis block above the old motor and replacing it with a brass plate to bridge the gap, which provided enough space for an open frame 5 pole with the shafts going through the bearing blocks from the original Farish motor. The motor itself was free-floating in the chassis, with just a couple of tabs to stop it trying to rotate under load. Ideal for DCC conversion as both motor brushes are insulated from the chassis.
Richard