Magnetic ballast

[nkalanaga]

I'm putting this in Product Discussion because of the results of my experiments.

I recently bought a small electronic scale, mostly for weighing mail, and decided to try it on some of my Pasco, WA, sand.  I've known since grade school, in the 60s, that the sand has magnetic material in it.  A large part of the sand is basalt, the rest Rocky Mountain rocks, all crushed and delivered by Ice Age floods.

To my surprise, by weight, Pasco sand is 1/4 magnetic material, probably magnetite, which is a common mineral in basalt.  I've been using it for over 50 years as scenery material, and have always glued it very solidly, but it could certainly be a problem if left loose, or poorly glued.

Just to be sure, I tried my magnet on Arizona Rock & Mineral Basalt ballast, #115.  To my surprise, it was ALL magnetic.  After picking out the magnetic portion, there was a very small amount of dust left.  I didn't weigh it, but suspect that it was at least 99% magnetic!

AR&M C&NW Pink Granite ballast, on the other hand, had no magnetic material.  That isn't surprising, as most granite doesn't have much iron.

[Dwight in Toronto]

I recently started using Scenic Express ballast.  Hobby shop proprietor advised magnetic screening before use.  I didn’t find one speck of anything magnetic. 

[signalmaintainer]

I'm putting this in Product Discussion because of the results of my experiments.

I recently bought a small electronic scale, mostly for weighing mail, and decided to try it on some of my Pasco, WA, sand.  I've known since grade school, in the 60s, that the sand has magnetic material in it.  A large part of the sand is basalt, the rest Rocky Mountain rocks, all crushed and delivered by Ice Age floods.

To my surprise, by weight, Pasco sand is 1/4 magnetic material, probably magnetite, which is a common mineral in basalt.  I've been using it for over 50 years as scenery material, and have always glued it very solidly, but it could certainly be a problem if left loose, or poorly glued.

Just to be sure, I tried my magnet on Arizona Rock & Mineral Basalt ballast, #115.  To my surprise, it was ALL magnetic.  After picking out the magnetic portion, there was a very small amount of dust left.  I didn't weigh it, but suspect that it was at least 99% magnetic!

AR&M C&NW Pink Granite ballast, on the other hand, had no magnetic material.  That isn't surprising, as most granite doesn't have much iron.

I'd be interested to know what would happen if Pasco sand was examined with a Geiger counter.

[Tristan Ashcroft]

I'd be interested to know what would happen if Pasco sand was examined with a Geiger counter.

Hahaha, so true.  It's never a bad idea to check with these sorts of things.

[djconway]

Danger - DANGER

I would never get magnetic sand any where near a model railroad.  No matter how well you clean it, you will never get all the magnetic particles out. The magnetic particles will eventually find their way into motors, gears, switch machines etc.

[Ed Kapuscinski]

Danger - DANGER

I would never get magnetic sand any where near a model railroad.  No matter how well you clean it, you will never get all the magnetic particles out. The magnetic particles will eventually find their way into motors, gears, switch machines etc.

Over how long though? And how long do we expect our layouts to last?
I've always wondered about that.

[wvgca]

i got sand blasting sand from princess auto .. eight or nine bucks for a fifty pound bag of the stuff ..i ran a strong pencil magnet through it before use, but i never found anything that stuck to the magnet

[nkalanaga]

SignalMaintainer:  Almost everything has some radioactivity.  But Pasco sand isn't unusually radioactive.  We actually measured it in high school, and it was well below safety limits.

There is uranium and thorium in the local rocks, but not nearly enough to make it worth mining.  Hanford is across the Columbia, and the waste tanks that have leaked go into the ground, not the air.  Background radiation isn't a problem in the Tri-Cities.

DJConway:  Motors are a problem, although I've never had any trouble.  Like I said, everything is very well glued.  I doubt that magnetic sand would be any worse than other ballast for N scale gears, because very few of our locos have steel gears.  A bigger problem is particles stuck to the grease, and magnetism wouldn't affect that.

Wvgca:  Here in Kentucky, I've been using "mortar sand", from a masonry supply.  Like your blasting sand, it's not magnetic, being local limestone.  Pasco sand is limited to scenery, usually gravel roads and parking lots, not ballast. 

Although, years ago, I did use it for ballast, and didn't have any problems. I still have a few locos from those early days, and the motors are fine.

[peteski]

Over how long though? And how long do we expect our layouts to last?
I've always wondered about that.

Depending on the location of the motor (with its permanent magnets) in the model, it only takes one run over the magnetic debris to pick it up. And now with all those cell-phone speakers (which have super-strong magnets in them)  located often in the fuel tank, and facing the rail, just fraction of an inch away), those are "magnets" for magnetic debris.  If bunch of that stuff gets stuck to the speaker diaphragm, it will likely cause distortion.  Think man, think!

[nscaler711]

One thing I've done to help with magnetic stuff in-between the rails is I have a tomix track cleaner where instead of the brush, I have a couple neodymium magnets in the recess. They do a pretty decent job of picking up track nails or other ferrous material. One could also modify the floor and raise it and stick a stronger magnet above so you can pick up more loose ballast.

[jagged ben]

Run stack trains with Kato containers with the exposed magnets in the bottom.  You'll pick up a fair amount of whatever loose magnetic material is between your rails.

[nkalanaga]

I have a pair of Aztec track cleaning boxcars with magnets, and pick up very little debris.  Once the loose spikes were rounded up, from construction, the magnets generally stay clean.