Minebea 15mm x 15mm DCC question


Dusty
 

Are these motors compatible with DCC over an extended period of use? Someone told me at one point in time that coreless motors didn’t like the pulse frequency modulation(?) method of speed control that DCC employs. While these aren't coreless they may have wire brushes that could be affected? I've ordered a couple motors and am curious. Any experiences to share?

Dusty Burman
623 261-8707


Scott Baker
 

Many experienced modelers on the "RepowerAndRegear" group are adamant about these motors. I recently ordered six of them from China for only about $2-3 a piece and shipping was cheap, fast, and smooth. I have not installed any of them yet, but I believe the story is that they are new units, but were rejected for quality control reasons due to loose wiring on the leads. I will remove the short wires and solder directly to leads anyway so no worries.  


Scott Baker
 

This is what they look like...


Mike Conder
 

Yours are wrapped?  Mine don’t have that wrapping. 

Mike Conder

On Mon, Mar 7, 2022 at 5:40 PM Scott Baker <sbake5570@...> wrote:
This is what they look like...

--
Mike Conder


Scott Baker
 

Mike, have you tested them yet, I'm curious about their performance? Without measuring, they look like they may barely fit in a Westside C-16, (taking up the cab space as the original motor).


Mike Conder
 

Not yet but it looks like they will fit a Westside C-16 … at least I hope so because I have one of the older ones with the motor in the cab. 

I did check the MDC HOn3 loco and it’s about 1 mm too wide unless it’s place in the firebox.  But that would require adding bearing supports for the worm (usually on the motor shaft) and a universal drive shaft or something. 

However I’ve also heard good things about the 10 mm square Minebea motor, basically that it will be enough to power an HOn3 loco smaller than a K-28.  Again, haven’t tried it myself and one needs a 1 mm x 2 mm shaft sleeve for that. 

Mike Conder

On Mon, Mar 7, 2022 at 7:43 PM Scott Baker <sbake5570@...> wrote:
Mike, have you tested them yet, I'm curious about their performance? Without measuring, they look like they may barely fit in a Westside C-16, (taking up the cab space as the original motor).

--
Mike Conder


Nigel Phillips
 

Hi Dusty,

Modern DC motors are also PWM. Old decoders had too low a frequency, anything built in the past 5-8 years should be compatible with a coreless motor. These motors run pretty slow anyway.

Heat dissipation is an issue with coreless motors, make sure they are well ventilated. Take that rubber sleeve off for starters. Probably best if the motor is held in place with some brass brackets soldered to the cab floor, rather than using (insulating) silicone.

Westside C16? No, unless some metal removal is undertaken. The motor bracket is too high for the new one. I got rid of it.  Easiest way is to lengthen the cab a tad (couple of mm is enough) using a PSC spare. That allows a cosmetic backhead to be used. Doing just that at the moment.

Nigel


On Mon, Mar 7, 2022 at 3:09 PM Dusty via groups.io <Dustburm=q.com@groups.io> wrote:
Are these motors compatible with DCC over an extended period of use? Someone told me at one point in time that coreless motors didn’t like the pulse frequency modulation(?) method of speed control that DCC employs. While these aren't coreless they may have wire brushes that could be affected? I've ordered a couple motors and am curious. Any experiences to share?

Dusty Burman
623 261-8707


Mike Conder
 

Thanks for the info Nigel. 

Mike Conder

On Mon, Mar 7, 2022 at 8:17 PM Nigel Phillips <nigelp18000@...> wrote:
Hi Dusty,

Modern DC motors are also PWM. Old decoders had too low a frequency, anything built in the past 5-8 years should be compatible with a coreless motor. These motors run pretty slow anyway.

Heat dissipation is an issue with coreless motors, make sure they are well ventilated. Take that rubber sleeve off for starters. Probably best if the motor is held in place with some brass brackets soldered to the cab floor, rather than using (insulating) silicone.

Westside C16? No, unless some metal removal is undertaken. The motor bracket is too high for the new one. I got rid of it.  Easiest way is to lengthen the cab a tad (couple of mm is enough) using a PSC spare. That allows a cosmetic backhead to be used. Doing just that at the moment.

Nigel

On Mon, Mar 7, 2022 at 3:09 PM Dusty via groups.io <Dustburm=q.com@groups.io> wrote:
Are these motors compatible with DCC over an extended period of use? Someone told me at one point in time that coreless motors didn’t like the pulse frequency modulation(?) method of speed control that DCC employs. While these aren't coreless they may have wire brushes that could be affected? I've ordered a couple motors and am curious. Any experiences to share?

Dusty Burman
623 261-8707

--
Mike Conder


Mark Kasprowicz
 

Not really Mike, the 15mm version is too long - if you are replacing the cab backs for a PSC casting it will certain not fit. I used Maxon motors from Eldon Shirley re remotor my WS C-16's.
The Minebea 15 is a six pole motor originally made to power motor vechicle wing mirrors. They are slow - around 7000  rpm at 12 v, resulting in a top speed that is perfect for narrow gauge. They are also powerful with excellent low speed torque.
Fixing is different as the mounting holes are on the diagonal, not either side of the shaft but I used silicon and that seemed to work well. I've used them to repower a number of brass K class locos and Mick Moignard has exchanged his Division Point K-36 Canon motor for one with excellent results. I too have not seen a cased one, all of mine (I bought 30 when they were just a dollar or two) have a metal casing. Not found a use for the 10mm, I thought it would fit that `goose I showed you the other day but it was way too big.
Tramfabriek.nl for the shaft sleeve for the 10mm (Dutch company based in England) though they are out of stock right now.
Mark


Nigel Phillips
 

Forgot to add that a) while the input to the decoder is essentially half wave AC with the high frequency control signal overlay, the output to the motor is plain vanilla DC, and b) DC power controllers are built so that the PWM is more pronounced at low speed, blending into continuous DC at high speed. As most modelers use perhaps 60% at most of the output, motors are using PWM all the time. That's why a good DC controller is amost as good as a DCC one for low speed running. One of the reasons why old controllers need to be retired - they are pure voltage output with high start values. Somewhere on the web are oscillographs of DC controller outputs. 

From my initial static test runs of those 15mm Minebea motors they do seem to be relatively rough running Probably why they are so cheap. 

Nigel




On Monday, March 7, 2022, Mike Conder <vulturenest1@...> wrote:
Thanks for the info Nigel. 

Mike Conder

On Mon, Mar 7, 2022 at 8:17 PM Nigel Phillips <nigelp18000@...> wrote:
Hi Dusty,

Modern DC motors are also PWM. Old decoders had too low a frequency, anything built in the past 5-8 years should be compatible with a coreless motor. These motors run pretty slow anyway.

Heat dissipation is an issue with coreless motors, make sure they are well ventilated. Take that rubber sleeve off for starters. Probably best if the motor is held in place with some brass brackets soldered to the cab floor, rather than using (insulating) silicone.

Westside C16? No, unless some metal removal is undertaken. The motor bracket is too high for the new one. I got rid of it.  Easiest way is to lengthen the cab a tad (couple of mm is enough) using a PSC spare. That allows a cosmetic backhead to be used. Doing just that at the moment.

Nigel

On Mon, Mar 7, 2022 at 3:09 PM Dusty via groups.io <Dustburm=q.com@groups.io> wrote:
Are these motors compatible with DCC over an extended period of use? Someone told me at one point in time that coreless motors didn’t like the pulse frequency modulation(?) method of speed control that DCC employs. While these aren't coreless they may have wire brushes that could be affected? I've ordered a couple motors and am curious. Any experiences to share?

Dusty Burman
623 261-8707

--
Mike Conder


Kent Schwarz
 

Kent Schwarz
Kaschwarz@...
Cell 303-718-2636


--
Kent Schwarz
SLMI HO/HOn3 layout club
Rocky Mountain Train Show Co-Chairman
Littleton CO


tom peterman
 

Scott, do you plan to leave the 'wrapper' on or remove it?
Tom Peterman


Mike Conder
 

Thanks Mark, good to know without tearing into things myself.  Don’t need to reinvent the wheel.  

And I got the sleeves I need from Tramfabriek a couple of months ago along with one of their motors for a rail bus rebuild. 

I’ll use the 15 mm for a SG loco I need for my dual gauge section. 

Mike Conder

On Tue, Mar 8, 2022 at 12:48 AM Mark Kasprowicz <mark@...> wrote:
Not really Mike, the 15mm version is too long - if you are replacing the cab backs for a PSC casting it will certain not fit. I used Maxon motors from Eldon Shirley re remotor my WS C-16's.
The Minebea 15 is a six pole motor originally made to power motor vechicle wing mirrors. They are slow - around 7000  rpm at 12 v, resulting in a top speed that is perfect for narrow gauge. They are also powerful with excellent low speed torque.
Fixing is different as the mounting holes are on the diagonal, not either side of the shaft but I used silicon and that seemed to work well. I've used them to repower a number of brass K class locos and Mick Moignard has exchanged his Division Point K-36 Canon motor for one with excellent results. I too have not seen a cased one, all of mine (I bought 30 when they were just a dollar or two) have a metal casing. Not found a use for the 10mm, I thought it would fit that `goose I showed you the other day but it was way too big.
Tramfabriek.nl for the shaft sleeve for the 10mm (Dutch company based in England) though they are out of stock right now.
Mark

--
Mike Conder


Mark Kasprowicz
 

Yes, the Minebea 15's are good smooth, slow speed runners and provided they wil fit, use them. I don't know of anyone on the repower group to find otherwise. Yes Sven is a useful asset in all sorts of areas. Great steam tram fan.
Mark


John Stutz
 

Dusty

There was a problem with coreless motors when run on pulse-power working a rectified mains frequency rates of 100 or 120 per second - the armature could actually cog along at the pulse rate.  This stepping is mostly a due to the very low armature inertia in this type, and persisted to a much lesser degree with early medium frequency DCC drives.  It is not a problem with modern high frequency DCC, and has never been a problem with any solid core armature motors.

John Stutz

On March 7, 2022 12:09 PM Dusty via groups.io <dustburm@...> wrote:


Are these motors compatible with DCC over an extended period of use? Someone told me at one point in time that coreless motors didn’t like the pulse frequency modulation(?) method of speed control that DCC employs. While these aren't coreless they may have wire brushes that could be affected? I've ordered a couple motors and am curious. Any experiences to share?

Dusty Burman
623 261-8707


Scott Baker
 

Tom, I have not thought about it yet. I suppose it would depend on fit. Right now I'm focused on structure building in preparation for a new layout.