Woulda, shoulda, coulda, magnetic uncoupling. Wish I would have gone with under track magnets but layout is mostly finished except for super detail parts. So this leaves the super magnet option. So what have you used, type, spacing, any proublems?
Sonicare toothbrushes have really strong magnets in the brush heads that you replace when they wear out. They are quite small like an eraser on a pencil and when inserted on either side of the track they work perfectly to uncouple cars. I just poke a hole in the foam, insert the magnet and then throw some ground cover over it.
I had some quarter inch square ones left over from another hobby. When I built the track scale module I put one under each rail across from each other on the approach rails to the scale.
I suppose you could get some quarter inch round and put one on each side. Or some 3/16 round and try inside the rails and cover with ballast. K and J magnets is my go to magnet shop.
Pete.
I use ⅛” diameter by ⅜” long Neodymium magnets for all kinds of goodies from uncoupling to keeping structures attached to my layout.
https://appliedmagnets.com/neodymium-magnets-1-8-in-x-3-8-in-rare-earth-cylinder-n42/
Simple ⅛" hole and your in business.
Mel
My Model Railroad
http://melvineperry.blogspot.com/
Bakersfield, California
Turned 84 in July, aging is definitely not for wimps.
Wooden bamboo skewers. I have always sort-of liked magnetic or other remote uncoupling, but the ability to uncouple anywhere eventually won out.
I still have a few magnets in awkward spots. Yeah, they are electro-magnets installed as the track got laid.
Magnets do nothing for units coupled with drawbars, which is all I run now.
You know all about Kadee magnets. N and S are along the edges so that the trip pins are pulled away from each other.
Now you can buy super magnets from All Electronics cheaply enough, but you can get the same for free for each old hard drive that you take apart. Same magnet and very strong.
TEST THIS MAGNET to determine how the trip pins react to it. In my experience they must be placed perpebdicular to the running rails instead on pzrallel as with a Kadee magnet. On the bench just put the magnet under a test track and see what orientation opens the trip pins.
I get my super magnets at Princess Auto (only in Canada, I think). A month-or-so ago I decided to try adding an uncoupling site to one of my industry tracks. While the area there isn’t yet finished, scenery-wise, the track had been ballasted (it’s directly on the plywood - no cork).
I sprayed a little “wet” water on the area, then used a screw driver to remove most of the ballast from between four ties, then used a #11 blade in my X-Acto to cut-away the connecting material between the ties, then pushed-apart the two ties in the centre.
Next, I used a “O” size drill bit (.3160" in diameter - the same diameter as the 8mm diameter of the magnets) to drill a shallow hole in the plywood on the inside of each rail, roughly 3mm deep, which is the thickness of the magnets.
I then place a small dab of WeldBond cement in each hole, then pressed the magnets in place, both with the same polarity facing up. The two ties were then pushed back to roughly their original position, just barely over the edges of the magnets.
Next, I added some ballast, groomed it, then sprayed the area with “wet” water and applied some diluted white glue.
The next day, with the glue set, I used a locomotive to push one car over the magnet, which opened both couplers and deflected the trip pins, allowing the car to be spotted where I wanted it.
I have 48 of those magnets left, and another 50 of the same diameter, but thinner…I’d double the thinner ones for uncoupling purposes.
That will be more than enough to do every industrial siding on my layout.
The benefit of using these small magnets is that there’s not a lot of mess created to install them in sites where the track has ballast or ground cover of some sort, and no need at all to take-up track, as would be required for Kadee under-the-ties uncoupling magnets.
I do have some of the larger rare earth magnets, which might work where uncoupling
Not to steal the thread, but how slow can you go and they not come uncoupled?
Thamks,
Richard
For mine, both the ones mentioned and the larger Kadee under-the-track or between-the-rails ones, they’ll uncouple while the train is not moving, with the couplers over the magnets. I don’t generally do flying drops.
Wayne
Early on, I removed all my under-the-track magnets from the mainline due to unwanted uncoupling. I now use them exclusively in yards and spurs.
I’m intrigued by these super magnets. I use uncoupling tools for mainline uncoupling but I do some switching of passenger cars and the diaphragms make that impossible. I’ve tried coming in from the side to seperate the pins but just can’t get the hang of it. I’m wondering if a few well placed super magnets at my main passenger station could be the answer.
How big are these magnets? Are they placed between the rails or outside the rails? Is unwanted uncoupling a problem? I’m not interested in the electro-magnets.
I got a bunch of the skewer type with lights but I just don’t like them as much. My whole layout is cork on foam except for an area around the turntable so drilling 1/8" holes is appealing as ballasting is done. What I am looking for are exact placement and how many in a row. How many in a row I have seen everything from 1 to 4. Is polarity important or just that they are both the same?
Most of my under-track or in-track Kadee magnets are in staging yards, and they work fine.
The magnets that I use (in my earlier post) are 8mm in diameter and 3mm thick. They’re located between the rails, with their outer edge roughly even with the inside edge of each rail. Both magnets need to have the same polarity facing up, and as long as you do so, it doesn’t matter which polarity (positive or negative) is the one that’s facing up.
Right now, I have only one in use, but when I get around to adding more, I’ll likely install the magnets with the same polarity as the originals, facing up. It’s easy enough to figure which side should be up, if I simply drop one near to the installed ones, as it will flip to match the ones already installed. These magnets are much more powerful than the ones most of us, as kids, used to play with.
I also have some bigger ones, but they’re considerably more powerful - any rolling stock running on wheelsets with steel axles might be stuck there forever…just kidding, but for uncoupling, they’d be overkill.
The small round magnets are easy to install, as long as you have a drill bit of the same size.
Wayne
Yes, uncupling can be an issue with these very slow locomotives. I followed the practice of the New York City Subway (on my last layout before I switched to model subways)… An use a cutting key. All this is is a momentary contact reversing switch, which ever so briefly reverses the direction of the locomotive. So briefly that an observer would not know what I did, but that is enough to uncupple the cars.
I used rods, 3mm dia, maybe 8 or 10 mm long, just outside the rails and between the ties. I did a row of 3 on each side, all the same polarity orientation on both sides. It did not work reliably. I have not revisited the issue, but closer together should work.
Dose the length mater and dose using a higher strength work better or more magnets at a lower strength?
It depends on what you want them to do. Just uncoupling you only have to overcome the weak knuckle spring. If you want to uncouple and push the car then you need more power to open the knuckle and overcome the centering spring. One magnet on each side should suffice. Any more power and you run the risk of unwanted uncoupling. When ordering magnets look at the pull strength. An N42 1/8x1/4 has a .86 pound pull.
Pete.
How about N48 1/8x3/8 Can get those for a good price.
Very easy to set up a test track. Will they work for uncoupling? Sure. About 1 pound pull should be powerful enough to uncenter the coupler but weak enough to avoid accidental uncoupling.
I put very powerful ones under my scale tracks. They cause accidental uncoupling if I pull a string of cars through. But used as intended (pushing cars) onto the scale rails they keep the car from rolling. It’s also what I had in stock without ordering. They were bought for holding the canopy on the frame of my RC helicopters and do a fantastic job at that. I’ve driven my 450 helicopter into the ground a few times and the canopy stayed with the wreck.
Pete.
Ok, set up test track and installed first sets of two, tried same polarity and oppisite, both worked. Got a curved test track too but will get to trying mags in that later. also need to figure out exact height and distance from rails, got the board, might as well do it all. They ussually work great and am working with #5’s and a set of clones just to be fair. Instaltion is real easy as it is cork on foam, just drill though cork and push into the foam, will proubly ACC the final layout ones.
As mentioned earlier I saved all the little magnets out of worn-out Sonicare toothbrush heads. To test placement distances I glued a couple on the end of two chopsticks to test things out. I suspended a length of track off the ground so I could move the chopsticks under as well as beside the couplers/cars to find where they worked best.