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hidden uncoupler magnets

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Posted by fwright on Tuesday, April 14, 2009 5:25 PM

pathvet9

On the other hand, I do not understand why it would not make a difference as to polarity of the magnets from one side of the track to the other. Wouldn't one side want to repel while the other attracts the coupling?

For successful uncoupling when there is slack, the magnetic field runs across (or perpendicular to the rails) the track.  This is set up by having a magnetic North pole near one rail, and a magnetic South pole near the other.  The uncoupling wires are simply iron wires, and are not magnetized.  They are drawn to the nearest magnetic pole, regardless of "polarity".  This is why the uncoupling wires are skewed off center, and why centering the in-track magnets below the coupler centerline is so critical.

With the rare earth cylinder magnets, a much stronger field is created when all the N poles are adjacent to one rail, and all the S poles are adjacent to the other.  But because of the intense fields of rare earth magnets and the non-polarization of the trip wires, such alignment may not be necessary for the magnets to work.

Final caution:  the delayed uncoupling feature of Kadees/MT requires more consistency in coupler mounting and stronger magnetic fields than just straight uncoupling.  The magnetic field has to pull the knuckle open against the spring (regular uncoupling) and then pull the coupler head to the side enough for the couplers to re-engage horn to knuckle so they won't recouple.  See the diagrams on the Kadee web site for more details.

yours in magnetic couplers

Fred W

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Posted by pathvet9 on Tuesday, April 14, 2009 8:27 AM

Karl - thanks for the clarification on uncoupling at slack. As I have never tried it, the principle was a little obscure but makes sense.

On the other hand, I do not understand why it would not make a difference as to polarity of the magnets from one side of the track to the other. Wouldn't one side want to repel while the other attracts the coupling?

Confused   Banged Head

Cheers, Jake ---------------------------------------- Patience when resources are limited
bdh
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Posted by bdh on Monday, April 13, 2009 7:10 PM

Cowman,

SKU is 95421 07001.  The manufacturer (distributor?) is Master Magnetics, Inc., Castle Rock, Co.  80104  www.magnetsource.com

Regards, Bruce H.
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Posted by larak on Sunday, April 12, 2009 8:42 PM

pathvet9

I assume that one must line up the magnets - on one side and + on the other??

I do mine that way but don't really know how much of a difference it makes.


 Also, if one uses 3 in a line in a yard, for example, what keeps the line from uncoupling as one is trying to build a manifest from that yard track?

 

The tension on the couplers from pulling or pushing the train keeps them coupled. Slack is needed to uncouple.

Karl

The mind is like a parachute. It works better when it's open.  www.stremy.net

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Posted by pathvet9 on Sunday, April 12, 2009 7:53 PM

Lothar and others - I am sorry to be so dense but I am missing something in this idea. I assume that one must line up the magnets - on one side and + on the other??

 Also, if one uses 3 in a line in a yard, for example, what keeps the line from uncoupling as one is trying to build a manifest from that yard track?

 Confused

Cheers, Jake ---------------------------------------- Patience when resources are limited
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Posted by cowman on Wednesday, April 8, 2009 8:47 PM

Bruce H.

Any idea what the Ace SKU is for the magnets?  My local Ace hardware man couldn't find a listing for magnets of this type.

Thank you,

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Posted by mcfunkeymonkey on Tuesday, April 7, 2009 1:58 AM

Atlas n-scale code 80 track has spaces between ties just a shade smaller than 1/8".

The D-22-N50 are 1/8"dia x 1/8" long and would fit nicely, except there's 1/4" - 5/16th space sideways, so the magnets would be touching each other (unless you can stagger them?)

The 1/16" dia mags have 1/4 the pulling power as the 1/8"dia.

It would be nice to have the smaller round ones work for n-scale: those kadee mags look fat (not phat) between the rails.

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Posted by Wazzzy on Tuesday, April 7, 2009 1:21 AM

well, with some expirementing, i found the perfect combination to make the uncoupling/delay action work every time. first was to ditch the older KD#5's and replace them with the 'whisker' couplers. there is less effort required to off-center the coupler for the delay action comparedc to the brass insert. second was to order the D24 magnets recommended in previous replies. i put 3 sets of 2 magnets flush with the tops of the ties as recommended. this combination works perfect with the code 83 track. i am happy that i spent a few nights of trial and error.

 PS - i have 10 EZ MATE uncoupling magnets for sale. make offer.

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Posted by loathar on Wednesday, March 4, 2009 8:08 AM

cowman

Last night I posted a thought about this and got an email on it, but it never posted here.  Must have gotten OOpsed as mentioned on the General Forums,

Anyhow, the Walthers Feb flyer has the small magnets on pg 34, 4 for $5.98.  Might even have set up suggestions, who knows.

Have fun,

I think those in the Walthers catalog are different than what we're talking about. Those look like 4 disk magnets glued to a plate. Probably has to be installed under your track before it's laid. (probably)

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Posted by cowman on Sunday, March 1, 2009 9:54 PM

Last night I posted a thought about this and got an email on it, but it never posted here.  Must have gotten OOpsed as mentioned on the General Forums,

Anyhow, the Walthers Feb flyer has the small magnets on pg 34, 4 for $5.98.  Might even have set up suggestions, who knows.

Have fun,

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Posted by LNEFAN on Sunday, March 1, 2009 12:22 PM

loathar

LNEFAN -Yep, they're really strong. Put a few in line for a longer uncoupling area. Paint to match your ballast and you can hardly see them.

I've been going back and forth on this magnet issue in my mind for a long time. I've been using skewers for uncoupling and they work well but in some areas I'd rather not reach over scenery. I really don't like the look of Kadee magnets and don't want to get into electromagnets under the layout. So the small ones seem like an option. I will not put them on any mainline track or passing sidings but for industries they may be just what I'm looking for. In any case, I do need to decide because my next big project will be ballasting and I want to place them (if I do use 'em) before I do that job.

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Posted by wedudler on Sunday, March 1, 2009 11:46 AM

 Magnets in a main track can be a problem. Therefore I've made some of my magnets moveable.

 Wolfgang

Pueblo & Salt Lake RR

Come to us http://www.westportterminal.de          my videos        my blog

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Posted by loathar on Saturday, February 28, 2009 9:56 PM

Wazzzy

i expiremented with the EZ-Mate under track uncoupler. very strong, too strong! gonna try the D24 meathod. how strong is the N42 compared to the N50?

The N50's are a little stronger. 1.08lbs of pulling force compared to .96lbs. Either will work for our purposes. You want to use the axial versions. There's a details section next to each magnet. Don't know how N scale coupler work or what they need. I'd suggest trying one that fits between the ties and is a bit longer. Maybe 1/2" for more pulling force.(???) That's just a guess though.

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Posted by cowman on Saturday, February 28, 2009 9:47 PM

Walthers Feb Flyer lists them on pg 34 for $5.98 for four of them. Might even come with instructions on how to place them, who knows?

Good luck,

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Posted by loathar on Saturday, February 28, 2009 9:42 PM

I put one on the inside of each rail right next to the rail. You can use 4 or 6 to make a longer uncoupling area if you like. Using only 2 gives you a pretty small target to try and stop on.

 

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Posted by grinstuff on Saturday, February 28, 2009 9:31 PM

so do you put them in the middle of the track between rails....on each side of a tie or side by side?

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Posted by Geared Steam on Saturday, February 28, 2009 5:38 PM

loathar

I used the 3/8x1/8, but I set mine flush with the top of the ties. You really don't need any longer than 3/8".

 

I took Loathars advice and purchased these magnets. I installed them in a couple on un-ballasted locations to test them out. I have them level with the tops of my ties, and they work great, I would recommend them.

"The true sign of intelligence is not knowledge but imagination."-Albert Einstein

http://gearedsteam.blogspot.com/

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Posted by Ngoody on Saturday, February 28, 2009 12:40 PM

Hi

Would size of magnet be any different for N scale?

thx

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Posted by Wazzzy on Saturday, February 28, 2009 10:35 AM

i expiremented with the EZ-Mate under track uncoupler. very strong, too strong! gonna try the D24 meathod. how strong is the N42 compared to the N50?

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Posted by yankee flyer on Tuesday, February 24, 2009 10:16 AM

loathar

I've been playing around with some of these.
http://www.kjmagnetics.com/products.asp?cat=13
(D-23, D-24)Drill some 1/8" holes between your ties and put a few in a row on the inside of each rail. You can hardly see them if you paint them.

Loather

Hy  Big Smile
These magnets seem like a good idea, I haven't been able to get the Kadees to operate correctly.I assume you need them to be "axially" magnetized when fitted in a hole drilled vertically? Both are available.
 Thanks

Lee

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Posted by MisterBeasley on Monday, February 23, 2009 7:02 AM

My rule of thumb about magnet placement:  The cars you are uncoupling need to be lined up on a straight track in both directions.  So, there needs to be straight track on both sides of the uncoupling zone, as long as your longest car or engine that will be uncoupled there in each direction.  You can relax this a bit for long passenger cars with truck-mounted "Talgo" couplers, because they align with the track, not the car.  So, don't put the magnet right after the curved branch of a tight turnout, for example, because the results will be less than satisfactory.

I've got one Kadee electromagnet, which I installed the hard way, from below after the track was down.  I would not suggest doing this.  "Dream, Plan, Build" became "Dream, Build, Swear" because I forgot Plan.  It works despite my lack of foresight, but it could have been easier.

The Kadee electromagnet takes a buttload of current, by the way.  I power mine off an independent wall-wart, to keep it completely isolated from train power.  I'm not sure how well it would run off DCC, but I would be careful.  You certainly don't want to run it directly off a decoder.  You might be able to power it indirectly, with a static decoder like those used for twin-coil switch machines.

It takes an iron man to play with a toy iron horse. 

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Posted by loathar on Sunday, February 22, 2009 9:46 PM

I used the 3/8x1/8, but I set mine flush with the top of the ties. You really don't need any longer than 3/8".

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Posted by larak on Sunday, February 22, 2009 9:17 PM

 http://www.forcefieldmagnets.com/catalog/index.php?cPath=23_37

 I use 3/8" dia 1/8 thick (thicker is stronger). You can even install after roadbed and track, before ballast. Top flush with bottom of ties.

Similar to Loathar's technique.

The mind is like a parachute. It works better when it's open.  www.stremy.net

bdh
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Posted by bdh on Sunday, February 22, 2009 7:27 PM

loathar

I've been playing around with some of these.
http://www.kjmagnetics.com/products.asp?cat=13
(D-23, D-24)Drill some 1/8" holes between your ties and put a few in a row on the inside of each rail. You can hardly see them if you paint them.

How far above the ties or below the railhead do you position the pole ends?  Also, I see they become stronger with an increase in length.  Have you experimented with anything longer than D-24?

Regards, Bruce H.
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Posted by loathar on Saturday, February 21, 2009 11:18 PM

LNEFAN -Yep, they're really strong. Put a few in line for a longer uncoupling area. Paint to match your ballast and you can hardly see them.

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Posted by cowman on Saturday, February 21, 2009 10:23 PM

The Nov 08 RMC has an article on the little round magnets used as uncouplers.  I have seen adds for them in MR and I remember another article, not sure where it was (might try the Index of Magazines), but it was about them.  Those seem to come 4 in a package and if I remember correctly they were used in a cluster and would help reduce the problem mentioned in RMC article about such a short uncoupling area.

God Luck,

 

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Posted by LNEFAN on Saturday, February 21, 2009 4:02 PM

loathar

I've been playing around with some of these.
http://www.kjmagnetics.com/products.asp?cat=13
(D-23, D-24)Drill some 1/8" holes between your ties and put a few in a row on the inside of each rail. You can hardly see them if you paint them.

I have seen these and comparable ones from other sources. Do they really work well?

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Posted by loathar on Saturday, February 21, 2009 10:11 AM

I've been playing around with some of these.
http://www.kjmagnetics.com/products.asp?cat=13
(D-23, D-24)Drill some 1/8" holes between your ties and put a few in a row on the inside of each rail. You can hardly see them if you paint them.

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Posted by bsteel4065 on Saturday, February 21, 2009 9:09 AM

I agree with JoeinPA. The Kadee magnets are very strong and I had a caboose with metal wheels that was pulled back and forth by the magnet if it stopped over it.

Cool

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