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I bought a small handful of motor & dummy trucks off da bay the other day, all die cast PW stuff that fits 2032, 2023, etc. One of the motor trucks is missing both magnets. Now, I can buy two purpose-made Alnico magnets from a parts supplier for $10 total, or for about the same $$, I can buy a small gob of neodymium magnets (likely much stronger than the original Alnico magnets) that are entirely too long. So here's the question(s):

1. If you cut a bar magnet (let's just say in half), do the two new pieces now take on the North/South properties of the original magnet, i.e. do both pieces have proper poles?

2. Are they each half as strong as the original?

3. If yes, can you now stack those two pieces, North on North and South on South, and get a single magnet with the same strength as the original? I would imagine stacking two opposing pole pieces would be easy, but stacking two same-pole pieces would be a bit like herding cats - dang near impossible, even with JB Weld!

They are on order for $12, so it's cheap enough to just experiment with, but I'm curious if anyone else has re-Magnetractioned a truck in this way?

Do you suppose that if this worked really, really well that you could now have a truck with so much magnetraction it wouldn't even want to roll down the track?

Aaaaah, Sunday mornings are great times for pondering....

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Magnets can and are made with a variety of materials. Not sure what you mean by really hard steel. However in the steel world the harder the still is the more brittle it tends to be.  Steel is made up multiple characteristics which are application driven. Magnets as well are application driven.

Neodymium magnets are very brittle. They also appear to lose strength as low as 175 f so beware.

I would think the easiest to cut is alnico. Ceramic or ferrite magnets would likely shatter. 

I have considered using neodymium magnets in magnetraction engines. They actually might be too strong causing too much drag for the motor to overcome but if you wanted to try fitting them and an exact size match wasn't available I would try and get shorter ones and fill the gap with soft iron bar to maintain the field.

Pete

Now that I'm reading the comments about the difficulty in cutting, that answers a question that arose while replacing the worm gear in a truck with Lionel's original magnets. Both magnets appeared to have been cut in a very jagged fashion, and I wondered why? Brittleness and difficulty in cutting could certainly explain that!

Well, all that said, I wonder if I could stack up and JB Weld a small pile of the "button" neodymium magnets to accomplish the same end? I wouldn't have the luxury of being able to adjust the "length" of the stack, but I could get lucky, and get close to an exact fit.

Just saw Pete's comments while typing this - good suggestions, think i'll give it a go!

 

My two toolboxes are were I store my magnets, there is an assortment of them all over the front, they've been there for years as well.

Pete, I wish I could find a dehumidifier that would last five years!

Stan, I've also bought a bunch of magnets from K&J, they're my go-to source if I need a magnet.  Interesting fact about how hard the material is, I've never tried to cut it, and I can see it would be "interesting".  That part about catching fire makes me think of magnesium.

I had better luck piping dehumidifiers versus using the reservoir. Can't remember the brand but bought at Lowe's. First one lasted 5 years in tool room in insulated metal building. That's in the high humidity Houston weather.

As for high powered magnets, their attraction can be dangerous. I hurt my thumb pretty good getting the skin between two neodymium magnets several years back. They were round about the size of a quarter.

I always run humidifiers to a drain, no reason at all to screw around with the bucket several times a day!   I currently have one that has the pump, but already the pump is getting noisy, something that I've heard is a major issue with most of these.  I'm going to have to figure out something more permanent for my dehumidifiers, it's getting old buying them all the time.

I got a real demonstration of the power of Neodymium magnets years ago at my brother's house.  He had some from wind generators, and he had a couple of them on the workbench.  They were a good six inches apart, and he bumped one of them and they suddenly felt a strong attraction.  Although they started out as cylindrical magnets over an inch around and about three inches long, there wasn't a piece larger than an inch long after the carnage!  There were sharp shards of magnet all over for quite a distance.  We both got several little cuts from flying magnet pieces, I'm glad I was wearing glasses!

My two got together on the bench from about 1 inch away, one dropped out of my hand and landed next to the other one.  One was pieces, the other one only had a corner knocked off.

I keep this one with the missing corner stuck to a parts cabinet on the workbench, it's great for magnetizing tools.  I use the Radio Shack VCR eraser to demagnetize them if I need to.

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Funny how the discussion evolved into dehumidifiers.  I have had 2 of them replaced on warranty in the last 5 years.  1 was about 5 years old and was under recall for fire risk and the other gave some code, which also indicated some sort of failure covered by warranty.  In both cases, I got full refunds, even though one was 5 years old.  

I understand about the ease of running them into the drain / sump, but I stopped doing that 5 years ago, when the one that was running into the sump crapped out, but the fan continued to run.  My other one was on the recall list and I had disabled it and was waiting for the refund before getting another.  So I had no operating dehumidifier and did not realize it, until I discovered mildew growing on my gargraves wood ties.  I just thought it was very humid that summer and the single one running was not up to the task.  A mistake I will never make again.  Went out and bought 1 that day.

I now have two 70 pint dehumidifiers running in my basement, neither draining to the sump.  It takes 2 to 3 days for both to fill up and trip off.  However, I know they both are running!  The gargraves track is long gone, replaced with Lionel tubular, with steel ties.

NWL

 

OK, a bit of a summary here.

1. Cutting magnets sounds difficult and like it would need some specialized tooling. Not worth it to me, I'll buy the precut ALNICOs first. 

2. It also sounds dangerous - I have certainly heard stories about bloodied, flattened skin when it comes to the really strong ones. Didn't really think about them shattering in more or less an explosion if they got too close - thanks for that heads up, @gunrunnerjohn !!

3. Thanks to @stan2004 for the heads up on the JB Weld and neodymiums. Again knew about it, just didn't even think about the magnetic pulling on the steel pieces!

4. Thanks to @Norton for your thoughts - I was also worried about the neodymiums being potentially too strong!

5. Thanks to everyone else for your thought and for chippin' in!

6. I also learned what a PIA dehumififers can be - 'course I already knew that, been running one (or more) in my basement in rainy Ohio for a lotta years. Don't need 'em now that I'm living on a slab in southeast Tennessee!

George

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