I was demonstrating NGS kits at the Poynton Model Show this weekend. A visitor told me that he had a number of Peco Jubilees, several of which had 'paper magnets' in their motors. I've never heard of such a thing ( I have come across magnetised paper and rubbers), but wound into a coil and used in an electric motor no.
Anyone out there come across this?
thanks in advance Norman
Not sure what he could have meant by that. The Rivarossi motor as used in the jub is pretty standard, with a ring magnet round the inside edge. Nothing "paper" like that I know of.
http://www.irwinsjournal.com/a1g/a1glocos/motors.html (http://www.irwinsjournal.com/a1g/a1glocos/motors.html)
Maybe something lost in translation here. I was thinking of "feuilles" in French meaning leaves and pages but also layers. The Rivarossi motor in the French 231 steam loco had a layered appearance on the magnet poles on the rotor. Just idle speculation.
Are these laminated armatures or magnets?.
Pretty standard motor construction as I mentioned earlier. Laminated armature.
Magnet not armature!!
The way the guy explained it to me was that the magnets were made from a strip of paper which was rolled (laminated) into a tube and then inserted into the housing of the motor just like the pictures in the link Nick sent. Perhaps I was not clear enough in my original post - I'm not querying a laminated magnet or use of a rubberised magnetic material - but I am querying the use of paper to make the magnet.
To make magnetic paper you would have to print it or coat it with magnetic pigment, like a car park ticket with a magnetic stripe.
Best regards,
Joe
"strange " shaped magnets can be made of paper, rubber and ceramic. Either the compound is made including a ferrous material or it is impregnated later - as with paper. Once the ferrous shape is formed it is then magnetized by applying a strong magnetic field which can have a custom pattern.
Its a very useful process.
An aside: the magnetic field, once created, is locked into the ferrous particles in the material. However, it gets unlocked with heat which is why you never want to overheat any magnet motor as it will be weakened permanently.
Last time I had a Rivarossi motor apart, pretty sure the ring magnet was formed of ceramic rather than paper.
I wonder if they are using amorphous magnet electric motors. If you were to describe an "amorphous magnet" to a "Lay" person, the best description would be a "paper magnet", as it is basically, super thin, and can be laminated to get the properties you require. They may even use paper to separate the laminates.
Amorphous magnet electric motors have been a long time coming to fruition, from what I remember they are about 25% more efficient than conventional iron or ferrite core motors, but do have some design limitations. With all the advancements in both electronics, and the need for more efficient electric motors for things like electric cars and bikes, may be they are starting small, and using it as a way to iron out any flaws, getting the bigger manufacturers to put a bit of R&D into them as well.
Well that's my best guess anyway.
Quote from: Lazy-Ferret on December 11, 2017, 01:41:47 PM
I wonder if they are using amorphous magnet electric motors... have been a long time coming to fruition...
We're talking about motors made in the 70s. If you look at the link I added in the 2nd post, there's a small photo and you can see the writer talks about a rubberised ring magnet.
Quote from: ntpntpntp on December 11, 2017, 03:17:43 PM
Quote from: Lazy-Ferret on December 11, 2017, 01:41:47 PM
I wonder if they are using amorphous magnet electric motors... have been a long time coming to fruition...
We're talking about motors made in the 70s. If you look at the link I added in the 2nd post, there's a small photo and you can see the writer talks about a rubberised ring magnet.
:sorrysign:
Ohhh.... sorry, I did not realise it was an old one... Probably not that then.. :no: