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RARE EARTH MAGNETS VS KADEE DELAY BETWEEN RAIL MAGNETS

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RARE EARTH MAGNETS VS KADEE DELAY BETWEEN RAIL MAGNETS
Posted by brianmarie on Friday, August 15, 2014 8:57 AM

I have several hard to reach uncoupling points that I can not reach with a skuer.  I have installed Kadee between rail delayed magnet uncouplers with mixed results, mostly bad.  They just don't seem to work.  I have heard of installing 1/8" dia. x 3/8" long neodymium rare earth magnets between the ties along the rails, 4 on each side, 8 per uncoupling point.

Has anyone used this or have a better idea.

Thank you,

Brian

  • Member since
    January 2001
  • From: SE Minnesota
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Posted by jrbernier on Friday, August 15, 2014 9:34 AM

  I suspect you may encounter 'Mixed Results' with any magnet.  Many of the rare earth magnets are stronger, so that may help.  Remember, the Kadee magnet is sort of 'split' and will pull the trip pin to the side.  A friend useds the rare earth 'super magnets' and installs them in pairs - Sort of two parallel rows of 4 magnets each.  This insures that the trip pins are pulled to the side.  Of course, curved track usually is a problem spot for uncoupling magnets, and if you have steel axles(like the old Athearn 'BB' freight cars, the car may 'center' a truck over the super magnets!

  My first layout used Kadee magnets and I found all of the above issues.  I finally started using 'skewers' - the magnets were not always where I really needed to uncouple a car.  The current layout has everything arranged so that I can use skewers - I learned my lesson!  I have accepted the 'Hand of God' dropping down from the sky to uncouple cars....

Jim

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by charlie9 on Friday, August 15, 2014 9:52 AM

Sounds kind of like a coupler problem, more than a magnet problem to me.

1-Are you using genuine Kadee couplers instead of the junk clones?

2-Do all of your couplers have the same style of centering device?  All springs or do some have whiskers?

3-Same question as number 2 but how about the knuckle spring?

4-Are your uncoupling points on straight, level track?

5-Whatever coupler you are using, are they properly installed and lubricated and are the trip pins properly adjusted?

I use the between the rails magnets on my layout for switching in the classification yard tracks and the cylindrical magnets for industrial sidings.  Both seem to work equally well for me except for the need to be precise in spotting the cars for the cylindricals.  There are some points where I use the skewer method if there is no magnet installed.

Good luck and be happy in your work.

Charlie

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    January 2001
  • From: US
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Posted by cmrproducts on Friday, August 15, 2014 9:57 AM

While the Rare Earth mangets will work -

I found (while operating on a layout this past week) that the magnets will pull the cars together and cause them to uncouple as you slowly pull across them!

YES! - It happened to me while I was running the Yard on this layout and the Train Crew was slowly pulling out of the Yard with 10 - 50 Ton 2 bay hoppers!

Everyone would pull together (as they ALL had Metal Wheels) and they uncoupled.

The Owner of the Layout was amaized when he saw it happening!  REALLY! :-)

I suggested he get rid of the Magnetic Uncoupling - or at least use an Electro Magnet

But in your case - in having unreliable results (as the Kadees have to be perfect to use the magnets - and this Layout Owners DID) you may not get the Electro Magnets to work for you!

But if you have them uncouple for you when you don't want - and it being a hard place to do so - it isn't going to be much fun for the crew of the train!

BOB H - Clarion, PA

 

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Posted by farrellaa on Friday, August 15, 2014 10:22 AM

I have some Kadee under track (in roadbed) magnets and also some 1/8" dia rare earth magnets. Both work but there is a difference. The kadee will pull a truck with metal axles over it and keep it there, but  it has a bigger target area for uncoupling. In the case of the 1/8" dia ones ( I only use 2, one on each side of the track inside the ties) and they work quite well but you have to be more accurate to position the couplers over the magnet. I haven't  had any accidental uncouplings unless backing over the magnets. I prefer the 1/8" magnets and will mark their locations with either signs or white paint on the ballast. Just my preference.

   -Bob

Life is what happens while you are making other plans!

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Posted by BroadwayLion on Friday, August 15, 2014 10:58 AM

Kadee magnets are special. North and south are not at the ends, but along the sides. Your rare earth magnets ought to work just fine if you put the crosswise rather than lenghtwise under the tracks.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by charlie9 on Friday, August 15, 2014 12:23 PM

BroadwayLion

Kadee magnets are special. North and south are not at the ends, but along the sides. Your rare earth magnets ought to work just fine if you put the crosswise rather than lenghtwise under the tracks.

ROAR

 Hey, Lion, did you ever try this yourself?  I have never placed the rare earth magnets across the track, between the ties.  I always drilled a 1/8 hole and stuck them down into it.  It never mattered which end (north or south) was up.
 
Charlie

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  • From: North Dakota
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Posted by BroadwayLion on Friday, August 15, 2014 1:57 PM

LION takes the rare earth magnets of him from discarded hard disk drives. They will not fit in an 1/8th" hole.

Him uses drawbars anyway, but uses them him does under the cars to trip the reed switch detectors. Orientation matters.

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by Southgate on Friday, August 15, 2014 5:49 PM

An alternative that I use; Hardware stores sell ceramic magnets, I use the 3/8x 7/8x 1 7/8 ones, mounted on edge, under the ties. They uncouple with all authority. I made mechanisms that physically raise these up in a slot when I want uncoupling, and they rest about an 3/4 inch below the bottom of the ties when not in use. Works great, I only use Kadees, and no steel axles to make trouble.

 The magnets are polarized edge to edge, not end to end.  I have only one that is not mechanically lifted for operation, in a spot that there is no room under the benchwork for it. It's on a stub siding.

You will want to observe the already mentioned issues, regarding only on a straight section of track, steel axles, etc.

Truth be told, I actually busted most of my magnets in half (did that years ago) and the halves work fine, but that's risky business with ceramic magntes, they break like, well, ceramic. Not always even or straight. I can show pics if anyone wants to see the mechanism. Dan

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Posted by brianmarie on Friday, August 15, 2014 6:56 PM

Thanks, I would love to see your mechanism.

 

Brian

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Posted by Southgate on Friday, August 15, 2014 8:02 PM

OK. I have company coming right now, but I'll get some pictures up as soon as I can. Dan

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Posted by Wazzzy on Saturday, August 16, 2014 10:03 AM

K&J Magnetics http://www.kjmagnetics.com/ has Neodymium magnets grade N52 1/8" x 1/4" (PN D24-N52). I used these on a small HO switching layout with great results. Drill a small hole in roadbed between ties at the far outside most possible location. Push magnet in flush with tie height. repeat on opposite side. Place 3 rows of magnets on eash side (not skipping tie spaces). Very reliable on straight track and maintained couplers. Place a 4th or 5th set if difficult to spot cars accurately. Delay coupling action is possible if wanted. Curves are the enemy with any magnet uncoupling technique.

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Posted by charlie9 on Saturday, August 16, 2014 10:47 AM

Wazzzy

K&J Magnetics http://www.kjmagnetics.com/ has Neodymium magnets grade N52 1/8" x 1/4" (PN D24-N52). I used these on a small HO switching layout with great results. Drill a small hole in roadbed between ties at the far outside most possible location. Push magnet in flush with tie height. repeat on opposite side. Place 3 rows of magnets on eash side (not skipping tie spaces). Very reliable on straight track and maintained couplers. Place a 4th or 5th set if difficult to spot cars accurately. Delay coupling action is possible if wanted. Curves are the enemy with any magnet uncoupling technique.

I have only used a single magnet on each side so far.  Did you orient the magnets so all the N or S poles were up on each side or does that even matter?

Charlie

 

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Posted by mikelhh on Saturday, August 16, 2014 8:11 PM

The neodymium magnets work beautifully.

I have them in two places on my layout.

I use 3mm cubes in strings of 5 - H0 gauge - and I find two strings will actually work although it is of course easier to sit over them if you have more than two. You have to align them the same, meaning each parallel string must be in the same north-south orientation.

In one place they're glued between the ties and in the other they actually replace the ties, and they were glued in place one string at a time after the ties were cut away. A lick of paint and it's very hard to tell the difference. You have to take your time gluing them, making sure each previous string is fully anchored before adding the next, because they're very strong.

The magnets never let me down.

Mike

Modelling the UK in 00, and New England - MEC, B&M, D&H and Guilford - in H0

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