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4 hours ago, maico said:

 Some Trix models use motors made by the German company Buhler. They make motors for all sorts of industries at reasonable cost

 

https://www.buehlermotor.com/en/products-and-markets/healthcare/healthcare-products/motors.html

Hi,

 

An interesting link but judging by their inductance they are not coreless. Also the motors they have in their catalogue now are mainly too large for HO.

 

Regards

 

Nick

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Before the arrival of the Mashima 1833 Buehlers were often used in O gauge due to the combination of good power output with low maximum rpm’s. I have gained the perhaps mistaken impression that the small round can motors used in some of the Heljan 4mm models were Buehler.

 

Izzy

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3 hours ago, Izzy said:

Before the arrival of the Mashima 1833 Buehlers were often used in O gauge due to the combination of good power output with low maximum rpm’s. I have gained the perhaps mistaken impression that the small round can motors used in some of the Heljan 4mm models were Buehler.

 

Izzy

AFAIK Bachmann used some Bühler motors in Branchline untill they sourced their own range.

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LGB use Buhler motors, for the power and smoothness they need.  They aren't coreless though.

 

IIRC there was a lot in the press in the 80's from Iain Rice and co that coreless motors were more powerful, but I suppose it depends what they were comparing them with.

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On 14/08/2020 at 01:23, flubrush said:

 

Putting a coreless motor,  like an RG4,  in a locomotive was certainly not ill-judged.   The higher, low speed torque of the coreless motor coupled with the high efficiency gearbox gave really excellent excellent speed control from zero.    If your interest was belting a loco and 12 up round a circuit at high speed,  then an RG4 could have been an ill-judged choice.

 

Jim.

Personally I always felt that the improvement in performance that the RG4 gave came far more from the gearbox than from the motor, especially if you had been previously using the Romford worm and wheel setup.

Given how important the motor/gearbox is to the performance of the model it seems to me odd to skimp on these items by buying cheap motors off ebay or similar, 'spoiling the ship for a haporth of tar' springs to mind

Edited by JeremyC
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I'm getting a sense of Deja-Vu here, we discussed the issues of coreless motors v feedback controllers a few months ago, but I can't find the thread now.

 

When Ricey and co were writing about this subject, the "normal" motorising option was some form of open-frame motor, and Romford worm/wheel gearing.   Feedback controllers (such as the ECM Compspeed) were developed to give better control of these sort of motors.  Coreless motors don't work well with feedback control, for the reason that they don't NEED feedback to run smoothly.  It was the appearance of the revolutionary  Portescap RG4 that led to ECM and Pendon to develop their controllers with switched levels of feedback. 

 

That was then, and this is now.  The current "normal" is some form of can motor, (Mashima) and engineered multi-stage gearbox, giving a performance just as good as an RG4.

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On 15/08/2020 at 05:07, NIK said:

Hi,

 

I thought from NCBs post that DC controllers are being built now that don't work with coreless motors. I assume they don't have a warning on the front of them about not using them with coreless motors.

 

Regards

 

Nick

 

If you take a look at Gaugemaster's web site they do mention which controllers aren't suitable for use with coreless motors. I expect the instructions with those controllers also contain a warning.

 

On 16/08/2020 at 01:52, maico said:

 Some Trix models use motors made by the German company Buhler. They make motors for all sorts of industries at reasonable cost

 

https://www.buehlermotor.com/en/products-and-markets/healthcare/healthcare-products/motors.html

 

Bachmann at one point used Buhler motors. Not sure why they discontinued. Possible far east products were cheaper.

Edited by NCB
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On 14/08/2020 at 11:32, cctransuk said:

 

I accept there has been this perception - but I was looking for hard evidence that they are invariably better than an iron-cored motor.

 

My suspicion is that the trend towards coreless is based on production costs.

 

John Isherwood.

 

The swiss company Maxon have quite a bit of info about brushed type coreless motors on their website. Quote:

 

"Coreless DC motors have no iron losses. In a conventional design the iron core permanently changes its magnetization. This consumes energy because the magnetic hysteresis loop must be run through at each shaft rotation. Additionally these flux variations induce Eddy currents in the iron core resulting in power losses that grow with the square of the motor speed. By contrast, in a coreless motor the magnetization is permanently impressed and constant. (The influence of the magnetic field of the winding can be neglected in a first approximation.) Hence there are no iron losses. As a result, the power losses are smaller, the efficiency is higher and the no-load current is lower. In an ironless design no saturation at the narrow parts of the iron core (at the base of the teeth) can occur. Hence the produced torque remains exactly proportional to the motor current and one can use the strongest permanent magnets without being limited by the maximum magnetic flux in the iron core. Improvements in magnet technology lead to stronger motors.

 

With a brushed coreless winding inductance is much smaller. There is less magnetic energy involved in the current switching process during commutation. This reduces the brush fire, the typical discharges that occur when the contact on an inductive load is broken up. The commutator-brush system is less affected and has a higher service life.

 

The reduced brush fire also creates less electromagnetic emissions."

 

From a practical point of view, I've found coreless are much smaller. The Marklin Trix E163818 motor used by Marklin and Trix in a number of steam locos measures only 25mm x 12mm. Fits into the smallest of boilers yet can drive all of the German Ho mainline classes. The ones in my Trix are made by Portecap. Trix charge 40 euros for a replacement with attached flywheel which is more expensive than their traditional horseshoe motors which are 25 euros (rotor and permament magnet)

Edited by maico
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6 minutes ago, maico said:

 

From a practical point of view, I've found coreless are much smaller.

That is one of the main advantages for model railways.

It's because the magnet is now where the iron core used to be so there is only the case outside the winding. No magnets to accommodate

 

The one thing I have noticed with the ones in the Oxford Dean Goods is there is much more stray magnetism on the outside than iron cored types.

Can't remember that with the Canon ones I encountered whilst at work.

Edited by melmerby
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Interestingly model trains is listed as a suitable use for the small Portescap Athlonix which has Neodymium magnet and precious metal commutation. Scroll down the page for tech specs.

 

https://www.portescap.com/en/products/brush-dc-motors/athlonix-motors/12g88-athlonix-brush-dc-motor

 

Insane price at RS, Marklin-Trix must have paid a fraction of that price...

https://uk.rs-online.com/web/p/dc-motors/8929097/

Edited by maico
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7 hours ago, maico said:

Interestingly model trains is listed as a suitable use for the small Portescap Athlonix which has Neodymium magnet and precious metal commutation. Scroll down the page for tech specs.

 

 

I would guess that these days neo magnets and silver comms/brushes are the standard even on the very cheap ones.

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8 hours ago, Steve51769 said:

Getting back to the OP, I have the same issue with my N7 - does anyone know the spec of a replacement can motor for the N7? 

 

Taken from my post on page 47 on the N7 thread: 'an alternative is a Tramfabriek 1020D (double shafted coreless 10 x 20mm) - I've used one on an Oxford N7 and it worked perfectly when I fitted it around 18 months ago and continues to do so today.  It's 3mm shorter than the original Oxford Rail motor, but is gripped by the foam in the motor clamp very securely so this isn't a problem.  You will need a 1mm dia. pin on a worm puller to swap the worm over from your old motor. 

See:

https://tramfabriek.nl/motors.html

The motor costs the Euros equivalent of about £16.50 incl. VAT and is posted from the UK, despite the 'nl' website address.  Not the cheapest priced motor but very nice quality and since I couldn't get one from Oxford Rail last year I was more than happy to pay the price having come across this one.  

I have no link other than being a happy customer.  The other motors they supply are worth a look, too.'

 

I also made the observation in a later post that the N7 of mine with a Tramfabriek motor is a noticeably better performer than my other two N7s with standard Oxford Rail motors (though, to be honest, they're pretty good anyway), which still holds true today.

 

Hope that helps!

 

Pete T.

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17 hours ago, melmerby said:

When the coreless motor in my Dean Goods failed a while back, Oxford sent me a replacement within a couple of days, replacement still working OK.

 

When the motor in my N7 failed in 2019, Oxford couldn't supply a replacement or give me any idea when they might have N7 motors available; in fact they expressed doubt that they would ever stock them as spare parts.  I don't know what the situation is today.

 

 

1 hour ago, melmerby said:

 

Quite so, and most of those listed on eBay in your search result are Tramfabriek motors, which were (probably still are, I don't know) a little bit cheaper to buy direct from Tramfabriek, rather than from their eBay listings.

 

Pete T.

 

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2 hours ago, PJT said:

 

When the motor in my N7 failed in 2019, Oxford couldn't supply a replacement or give me any idea when they might have N7 motors available; in fact they expressed doubt that they would ever stock them as spare parts.  I don't know what the situation is today.

 

 

 

Quite so, and most of those listed on eBay in your search result are Tramfabriek motors, which were (probably still are, I don't know) a little bit cheaper to buy direct from Tramfabriek, rather than from their eBay listings.

 

Pete T.

 

 

 

Pete

 

How old was your loco when it became faulty? whilst companies try and claim that an item is guaranteed for 12 months, the sale of goods act requires an item to be useable for much longer, the more expensive the item is then the longer you can expect to use it. As it stopped 3 years ago I expect you may have missed out

 

Now there is a second piece of law is that manufacturers are expected to maintain spares for a reasonable period of time.

 

As for motors, I bought 4 option C motors. They are coreless, though 6v, but as they are for small tanks they will never be thrashed. $12 inc postage for all 4 you cant go wrong

https://www.ebay.com/itm/193592365341?hash=item2d1301111d:g:aOMAAOSwyo1fGUNn

 

I have just ordered 2 of these coreless motors, rated at 12v, though shows speeds (RPM) between 3 to 18v, Just over £7 each + postage but as the others were great value, I thought I would have a try. Plus its nice to have a smaller motor option

 

https://www.ebay.co.uk/itm/194179021555?hash=item2d35f8baf3:g:xUAAAOSwu-Jgwxpv alternative

Edited by hayfield
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43 minutes ago, hayfield said:

How old was your loco when it became faulty? whilst companies try and claim that an item is guaranteed for 12 months, the sale of goods act requires an item to be useable for much longer, the more expensive the item is then the longer you can expect to use it. As it stopped 3 years ago I expect you may have missed out

 

Now there is a second piece of law is that manufacturers are expected to maintain spares for a reasonable period of time.

 

Good evening John,

 

Well, I have to confess I bought the loco reasonably cheaply knowing that the motor was hit and miss in its operation, so unless I made some kind of fraudulent claim there wasn't any warranty or pushing Oxford for a replacement motor under their service commitment for me on this occasion.  By the way, having worked in the motor industry, both in car manufacture and original equipment car parts manufacture all my working life, I'm very aware of the 'service commitments' that motor manufacturers are bound by, similar in principle but longer in period than the sale of goods act commitments you're alluding to, including guaranteed supply of spares to keep a car functioning and roadworthy for 10 years after its production. 

 

On this occasion I thought I could persuade the motor to work properly, as I've done dozens of times with other non-working/intermittently working locos, but on this occasion I just couldn't get it to start and run reliably.  Then it gave up altogether, so I went in search of a suitable replacement and discovered the Tramfabriek range.  Actually, I enjoy this sort of repairing and problem solving and frequently buy cheaper non runners to entertain myself with, so the story of my failed N7 wasn't an unhappy experience at all, and I'm delighted with the finished repair!

 

43 minutes ago, hayfield said:

As for motors, I bought 4 option C motors. They are coreless, though 6v, but as they are for small tanks they will never be thrashed. $12 inc postage for all 4 you cant go wrong

https://www.ebay.com/itm/193592365341?hash=item2d1301111d:g:aOMAAOSwyo1fGUNn

 

I have just ordered 2 of these coreless motors, rated at 12v, though shows speeds (RPM) between 3 to 18v, Just over £7 each + postage but as the others were great value, I thought I would have a try. Plus its nice to have a smaller motor option

 

https://www.ebay.co.uk/itm/194179021555?hash=item2d35f8baf3:g:xUAAAOSwu-Jgwxpv alternative

 

...and thank you very much for taking the time to offer both of those recommendations.  I've saved them for future reference and I'll probably order one or two anyway, just to have a look at them and see what they're like.

 

Pete T.

 

Edited by PJT
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12 hours ago, PJT said:

 

Good evening John,

 

Well, I have to confess I bought the loco reasonably cheaply knowing that the motor was hit and miss in its operation, so unless I made some kind of fraudulent claim there wasn't any warranty or pushing Oxford for a replacement motor under their service commitment for me on this occasion.  By the way, having worked in the motor industry, both in car manufacture and original equipment car parts manufacture all my working life, I'm very aware of the 'service commitments' that motor manufacturers are bound by, similar in principle but longer in period than the sale of goods act commitments you're alluding to, including guaranteed supply of spares to keep a car functioning and roadworthy for 10 years after its production. 

 

On this occasion I thought I could persuade the motor to work properly, as I've done dozens of times with other non-working/intermittently working locos, but on this occasion I just couldn't get it to start and run reliably.  Then it gave up altogether, so I went in search of a suitable replacement and discovered the Tramfabriek range.  Actually, I enjoy this sort of repairing and problem solving and frequently buy cheaper non runners to entertain myself with, so the story of my failed N7 wasn't an unhappy experience at all, and I'm delighted with the finished repair!

 

 

...and thank you very much for taking the time to offer both of those recommendations.  I've saved them for future reference and I'll probably order one or two anyway, just to have a look at them and see what they're like.

 

Pete T.

 

 

 

Pete

 

Sorry I either missed or it was not stated the point you bought the loco as a poor/non runner. However as you say now its a legal requirement that spares are available, and as this company still sells locos I am surprised they do not have an alternative

 

I like the idea that you enjoy restoring locos, as far as RTR is concerned this was quite easy until the Chinese produced locos arrived, now there seems endless issues with wheelsets, gears etc are causing endless issues. I also enjoy breathing new life into kit built locos, which seem far easier to repair as far as mechanisms are concerned

 

I have had a few issues with a couple of coreless motors failing, Tramfabriek replaced a motor very quickly without issue, which proves dealing with a decent importer pays off

 

I have also had a really good experiences with both a High Level coreless motor and RG4's.  The latter being quite sought after due to its quality and gearbox , the High Level motor is a super quality item, especially for kit built locos in conjunction with their gearboxes 

 

One motor I left out was the N2 (might be N20) which has been used by many to good effect but its not coreless

 

One possible note of caution is to use a modern controller, many of us use older H&M controllers especially on out workbenches, they may send out too much in the way of amps ?

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16 hours ago, PJT said:

 

When the motor in my N7 failed in 2019, Oxford couldn't supply a replacement or give me any idea when they might have N7 motors available; in fact they expressed doubt that they would ever stock them as spare parts.  I don't know what the situation is today.

 

Pete T.

 

26th June 2019 I e-mailed Oxford, new motor received within the week.

They said it was the same type as now used in several locos.

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Hello again John,

 

1 hour ago, hayfield said:

Sorry I either missed or it was not stated the point you bought the loco as a poor/non runner. However as you say now its a legal requirement that spares are available, and as this company still sells locos I am surprised they do not have an alternative

Both times I've contacted Oxford to see if I could purchase a motor - once for the open frame motor in an Adams Radial, the other for the N7's coreless type - I was simply told they didn't have any, not even in returned locos that they might 'Christmas Tree' for spare parts, and that they had no idea when or even if they might have them in future.  I was surprised, too.  Still am.

 

1 hour ago, hayfield said:

I like the idea that you enjoy restoring locos, as far as RTR is concerned this was quite easy until the Chinese produced locos arrived, now there seems endless issues with wheelsets, gears etc are causing endless issues. I also enjoy breathing new life into kit built locos, which seem far easier to repair as far as mechanisms are concerned

Oh, I repair kit built locos too, though nowhere near as many as RTR.  I find the majority of non running kit builds need pretty much complete disassembly and rebuilding and, to be honest, I have enough already in the kit stash that I ought to be spending my time on instead.  One I did do last year was a K's Bulldog 4-4-0 with the usual broken nylon outside cranks, but otherwise nicely finished.  A new set of wheels and cranks, plus the addition of a boiler backhead and fall plate that K's never supplied in the kit, and it's beautiful; very, very satisfying.  The grandson's following in my footsteps now, buying, repairing and selling locos to fund the ones he wants to buy for his own railway.  Not that I encouraged him or anything...

 

1 hour ago, hayfield said:

I have had a few issues with a couple of coreless motors failing, Tramfabriek replaced a motor very quickly without issue, which proves dealing with a decent importer pays off

Exactly!

 

1 hour ago, hayfield said:

I have also had a really good experiences with both a High Level coreless motor and RG4's.  The latter being quite sought after due to its quality and gearbox , the High Level motor is a super quality item, especially for kit built locos in conjunction with their gearboxes 

 

One motor I left out was the N2 (might be N20) which has been used by many to good effect but its not coreless

I've never used a High Level coreless motor, though I ought to try them because you and many others speak very well of them.  I've used loads of Portescaps, many bought cheaply in basket-case kit builds.  They seem sometimes to be fitted in the vain hope they'll be a magic cure for a badly built chassis.  Never used an N2/N20 - I'll look into that, thank you.

 

1 hour ago, hayfield said:

One possible note of caution is to use a modern controller, many of us use older H&M controllers especially on out workbenches, they may send out too much in the way of amps ?

I know; you wouldn't buy a new car and fill the engine with 1950s technology SAE 30 oil, would you?  New controllers are, in the main, cheaper than new locos; why would you risk a new loco with a very old controller?  Through a sentimental inability to throw it away, I've still got an old Rovex controller that came with my first train set.  I'm sure it still works ok, but I wouldn't ever consider using it nowadays.

 

Pete T.

   

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34 minutes ago, melmerby said:

26th June 2019 I e-mailed Oxford, new motor received within the week.

They said it was the same type as now used in several locos.

Well, Keith, all I can say is that you were lucky and I wasn't (and it wasn't the first time I'd asked them for a motor and been turned down, so I was half expecting it the second time, with the N7).  Maybe I contacted them a while before you and the situation changed in the meantime.  I did say I didn't know what the situation's like today.  Obviously it's great news and peace of mind for owners if they are now available!

 

Pete T.

 

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  • 2 months later...

A follow up to my earlier posting re. Stalling Oxford Rail N7. Thanks to the advice from PJR I purchased a new motor from Tramfabriek and have fitted it. It has the advantage over the original in that it has an additional flywheel. It now runs beautifully and very controllably. Job done.

 

Steve

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