Neodymium magnets

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senorsenales
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Neodymium magnets

Postby senorsenales » Tue Mar 03, 2015 10:00 am

I have been looking at various youtube videos about neodymium magnets for uncoupling Kadee couplers, but they didn't have any advice on suitable magnet sizes. Oblong seem best but it was the thickness and strength I couldn't get any information on.

Any help please, thanks

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End2end
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Re: Neodymium magnets

Postby End2end » Tue Mar 03, 2015 11:29 am

IF it's any help, I have been looking at these. 3 x 4mm Neodymium rod magnets.
http://www.ebay.co.uk/itm/181666289694? ... EBIDX%3AIT
Image
Put 2 inbetween a pair of sleepers for stronger pull and put pairs 3 sleepers apart so it catches BOTH couplings.
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Bufferstop
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Re: Neodymium magnets

Postby Bufferstop » Tue Mar 03, 2015 3:25 pm

I use these magnets as well, mine are for the Bachmann narrow couplers with magnetic tails(staples) attached. 3mm dia , 4mm long should do. find them at http://www.first4magnets.com. When it comes to planting them on the layout you will need some kind of non magnetic tool. I use a length of brass tube with a straightened paper clip passing through it. Pick up a magnet with the paperclip extended, place the magnet where desired, press it down with the tube and retract the paperclip. Keep the rest of the magnets well away from the ones you are planting, they don't like being seperated from their friends and will leap up to a foot or so to rejoin them. Downside to using permanent magnets, steel axles. If the magnet is too strong the axles will pull the wagon forward then try to stop it moving on. Push the magnet deeper into the board to weaken its field.
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skyblue
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Re: Neodymium magnets

Postby skyblue » Tue Mar 03, 2015 3:31 pm

Probably a good idea to keep them away from credit cards/phones etc. just to be safe.

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Re: Neodymium magnets

Postby Bufferstop » Tue Mar 03, 2015 5:34 pm

They sent me a promotional pack of magnetic map pins (so you can hang papers on the sides of filing cabinets), I was playing around chasing Oxford diecast vehicles around a thin topped table, let go of one which promptly made for the one I was holding, won't be doing that again anytime soon :oops: . As far as I can tell the only steel in the cars was the axles but they followed the magnets around quite well.
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senorsenales
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Re: Neodymium magnets

Postby senorsenales » Tue Mar 03, 2015 8:31 pm

Thanks for that, I was looking at these ones https://www.youtube.com/watch?v=fWr6WOlnVGk but there weren't any dimensions on there. Seemed to be very effective overall.

The round ones I saw here https://www.youtube.com/watch?v=LGyVfSyDlp4 but wasn't too taken with them.

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End2end
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Re: Neodymium magnets

Postby End2end » Tue Mar 03, 2015 9:21 pm

senorsenales wrote:The round ones I saw here https://www.youtube.com/watch?v=LGyVfSyDlp4 but wasn't too taken with them.

To be honest senorsenales the 2nd place he has placed them looks a damn awful mess.
The 1st point where he has installed them looked good, don't know why he hacked the track to bits for the 2nd position.
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Emettman
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Re: Neodymium magnets

Postby Emettman » Tue Mar 03, 2015 9:48 pm

End2end wrote:
senorsenales wrote:The round ones I saw here https://www.youtube.com/watch?v=LGyVfSyDlp4 but wasn't too taken with them.

To be honest senorsenales the 2nd place he has placed them looks a damn awful mess.
The 1st point where he has installed them looked good, don't know why he hacked the track to bits for the 2nd position.
Thanks
End2end


From the rest of the video, the second installation seems sufficiently over-the-top to cause problems.

Having just done a couple of experiments I am definitely, as suggested, going to go with ramp-free magnetics to finish my modified tension-lock couplings.
This is helped by having a good supply of craft wire which is adequately magnetic, soft, and rigid. The last two meaning it can be adjusted in place but will then hold that adjustment.
I also have some small magnets which come from the steering units of the tiny r/c cars I have been cannibalising.
At the moment, with my single hook couplings, I seem to be getting the best effect with a single magnet, its top surface 1mm above the sleeper surface: enough to get a firm reaction from the hook, but not producing a visible effect on wagons with metal magnet-attracting axles.

Chris
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Bufferstop
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Re: Neodymium magnets

Postby Bufferstop » Tue Mar 03, 2015 10:08 pm

The 3mm x 4mm rods have sufficient strength to be set flush or just below the surface of the ballast. A dab of paint on the top disguises them to the point that I've had to resort to clues placed alongside so that I know where they are!
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Emettman
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Re: Neodymium magnets

Postby Emettman » Wed Mar 04, 2015 9:07 am

Given the source, there's a fair chance my magnets may not be of the highest performance for their type, though they re pretty strong.
The alternate would be that I have not yet got the dropper wire to its best position.

Yes, I had had thought of the need for location markers: this I've done on my G scale exhibition layout, where the uncouplers only have a couple of cm of working length. "ruddy obtrusive" does have its uses.


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End2end
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Re: Neodymium magnets

Postby End2end » Wed Mar 04, 2015 3:49 pm

Emettman wrote:"I've got some superb camouflage gear, but I can't find it."Chris.

:lol: :lol: :lol: :lol: :lol: Hilairous!!!!
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senorsenales
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Re: Neodymium magnets

Postby senorsenales » Wed Mar 04, 2015 9:07 pm

Ok thanks for that, I will be installing in new track so I am going to have a look at the flat ones first, they seemed to be just that bit more tidy.

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Boxcar Willie
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Re: Neodymium magnets

Postby Boxcar Willie » Sat Mar 21, 2015 11:44 pm

I got one from somewhere to replace the weak old on one in a loco I had. The loco was an old Triang/Hornby 8f from the late 50s/early 60s and at this stage it should probably be out to grass but I installed the new magnet, put the loco on the club's test track and watched fascinated as a model that is actually older then myself shot round the circuit at a scale 600 mph.

I have to be careful as the old loco's innards may not be able to cope with the humungous power that the molybdenum magnet provides. It's a bit like putting a Ferrari engine in a garden strimmer.


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