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I ran into an interesting problem recently. I'm working on a bottom unloader for my fishbelly hoppers. My latest attempt involved using magnets to keep the hopper doors shut. My coal load is the coal slag abrasive stuff from Tractor Supply. I love how it behaves and looks!

But apparently there is something magnetic in it. It's sticking to the magnets on me. This creates juuuuust enough of a gap in the bottom doors that more coal can get through and make a biblical mess on my test layout (I'm am so glad I build a test layout before diving into the full thing). Does coal/coal slag typical carry traces of iron/ferrous metals?

The search bar revealed many companies selling real coal loads but didn't make much mention of plastic loose coal (just mentioned the inserts that come with cars). Plastic coal is probably the solution in my case but I don't think the Lionel version looks great and I didn't see other options for plastic. I saw a guy use chip chopped rubber and that looked decent but there are two problems with that: I don't think the rubber will slide down plastic ramps well and I need a LOT of coal.

So if I seek out some of these real coal loads, can anybody guess if I am still going to run into the magnetic problem? I was hoping someone might have some coal from one of the companies that is still around and they could go put a magnet in their coal and see if anything sticks to it.

EDIT: Apparently you get the best results in the search bar if you post a topic and then return to searching aquarium rocks might be the ticket to get me by. Just found someone mentioning it. I'm a little concerned about weight but I suppose it gives me an excuse to double head some articulateds for bigger, badder coal drags.

Last edited by BillYo414
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The stuff you learn on this forum!  I have slag and real coal from Scranton but I am not using magnets on my hoppers so all of it stays in place with some elmers glue.  I have seen comments about black acquarium sand but have yet to try it.  Have you tried real coal and then put it in a heavy bag and hammer it to the size you want.  Lionel plastic coal is not realistic at all, as you have said.

Haha @POTRZBE it's a gem, for sure.

Is real coal too dirty for our purposes? I imagine I would need to remove my fines and maybe I would be good. The coal slag dust is minimal so far.

I have some black sand on the way. I considered activated charcoal but I thought it might break down over time. There are a few Etsy shops that appear to be selling aquarium gravel that looks like what I need but my concern is sourcing it twice. I worry they only sell it because they picked up at a garage sale or something. So I tried the sand. We'll see how it works! I'll report back.

@BillYo414 posted:

The only demagnetizer I know of is the ones I have seen for screwdrivers. Do you think pouring the coal through one will work?

@Avanti good to know about anthracite. The local steam/stationary club might be able to spot me some. I don't know if it's expensive.

When I was a lad, anthracite was $5.00 a ton.  Of course, we lived over a coal mine in the semi beautiful Scranton area.  Could it have gone up that much?

@BillYo414 posted:

The only demagnetizer I know of is the ones I have seen for screwdrivers. Do you think pouring the coal through one will work?

Put it in a bag and turn this loose on it.  I use one of these for demagnetizing tools and anything else.  It's certainly powerful enough to do the job!

Search eBay for radio shack tape eraser, I got lots of hits, they're cheap.


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@Craftech posted:

I bought 2 bags of artificial coal from Jeff at Train Tender for my coal loader.  I just checked it with a magnet.  It didn't stick.  I think it looks good.  I can post a photo if you like.

Train Tender Parts List



4 oz bag of artificial coal


A picture would be great! I'm looking at all my options. The sand is supposed to be here today. It was only a few bucks so it's not a loss if it doesn't work. Thanks for that second link! It might be the answer.

@POTRZBE posted:

When I was a lad, anthracite was $5.00 a ton.  Of course, we lived over a coal mine in the semi beautiful Scranton area.  Could it have gone up that much?

I love Scranton. The anthracite museum and train museums are killer!! I have never bought coal but I'm glad I don't need 1 ton. @Dennis-LaRock says $160 a ton haha

@gunrunnerjohn that's a handy little gadget. I might pick one up just to have. My only question: if the coal I have just happens to have bits of iron in it, will that still work?

I appreciate the help guys. I got a quote back to have springs made and it was quite expensive. So it looks like my best bet is to stick with the magnets and find suitable coal.

On the upside, the unloader concept works. I just need to work on the design. So I'm on the home stretch if you don't count figuring out Arduino programming for the sensors and whatnot.

@BillYo414 posted:
@gunrunnerjohn that's a handy little gadget. I might pick one up just to have. My only question: if the coal I have just happens to have bits of iron in it, will that still work?

It's demagnetized everything I've pointed it at.   The trick is, place it on the object to be demagnetized, pull the trigger, than then holding the trigger, slowly move the demagnetizer away several feet.  I've even demagnetized magnets with it, just to see if it would work.

I got my bag of sand in the mail today. (never thought I would put those words together in combination haha)

IMG_20210614_193137898SAND Sand

IMG_20210614_193143179_HDRCOALCoal slag


Honestly, I think it'll do. It's a bit more dull than the coal slag but I do believe this is a case where having ALL sand will make that dullness less apparent. I also think the people reading this thread are the only people that would ever even notice because they're aware. I'm also open to sacrificing a little bit of realistic appearance for the operational realism. I had a good time by myself shuffling hoppers around and unloading them to test how the sand flows.

The sand seems to catch a bit of static electricity or something. It's got a bit more of a tendency to stick to the rails than the coal slag. It clumps up in the hoppers like the coal slag though. I also noticed more fines in the sand but that's probably because I emptied the bag. I never made it more than three pounds into the bag of coal slag.


I suppose I'm not too concerned about the sand on the rails because I had already intended to remove some material in to reduce material even getting stuck anyway.

I'm thinking this is the solution I'm going to go with. It seems to have less dust than the coal slag as well (just has some fines in it). Hopefully it stands the test of time. I don't know if it's dyed black or actually black. It's not as cost effective as the coal slag but I guess I'll live. I'll have to spent some more time emptying it to see if it escapes the hoppers or sticks to plastic too much but this definitely looks promising.

Thank you all for the help! This thread is going to serve some people will in the future.


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Bill, I'm glad you're happy with the way the sand is working in the hoppers.  I would offer a word of caution from personal experience maintaining full size equipment operating in and around sand.

Sand will readily stick to exposed grease and oil.  Sand with static cling could be especially problematic.  When grease/oil is in place to lubricate gears and moving parts, the grease/oil becomes an abrasive paste, greatly reducing the useful life of those parts.

@SteveH that's been in the back of my mind. I know sand doesn't get along with mechanical movement. I was hoping just being a little more aggressive with maintenance would be the ticket. I chewed up gears on an RS3 as a kid by using loose gravel for ballast and not knowing how to glue it down.

The other good news is that locomotives won't cross over the unloader very often in the course of operation. It's a dead end (and 4 foot drop) beyond the unloader. So I think/hope that will make a difference and prevent sand from getting into drivetrains. So far the coal on the table in the picture has been coal I spilled so we'll see.

Lumber is still expensive and I still need to get the walls/ceiling ready for a table to even be built so I have a few months to play around and see how it works out.


That sand looks pretty good! I do share the concern with others regarding the static cling issue. Not certain how to deal with that for your application. You may need to add a "reach" car or 2 between the engines and the hoppers to keep the engines away from the loose stuff.

Where did you order the sand? Do they have other colors and/or sizes?



I know you're supposed to keep quiet and be thought an idiot, rather than open your mouth and remove all doubt...but! I was thinking that I could ground the piles of sand somewhere to get rid of the static build up. I suspect it builds up in the clear PVC pipe it moves through so I thought maybe I could ground that or use different material. The end of the project involves the sand being carried through that pipe almost 8 feet so I need to solve that if it's the source of static build up. I think static electricity builds up from items rubbing against one another and electrons being traded but not returned. There must be a way to remove static up build up (is that degaussing?).

The sand is Estes' Stoney River Premium Aquarium Black Sand. I got the first back off Amazon but a somewhat local (30 miles) pet store has some in stock so I'm going there to buy more rather than pay for shipping dead weight (I don't have or want Amazon Prime). The Estes' website says they have other colors and sizes. I'm happy with it. Like I said, the cost kind of stinks but the operational gains are well worth it for me.

Bill, as you already seem to understand, since sand is primarily silicon it's essentially a non-conductive material.  When cutting PVC (trim and pipe) with a power saw, to prevent the shavings from sticking to everything, I've had success spraying Static Guard on tools and materials to minimize this.  Static Guard essentially creates a conductive layer on the outside of otherwise non-conductive materials.

Here's a link to a basic explanation of how it works:

Maybe worth a try.

@SteveH posted:

Bill, as you already seem to understand, since sand is primarily silicon it's essentially a non-conductive material.

Maybe worth a try.

I didn't know that, actually. But I also didn't know Static-guard existed. That's a clever idea and seems like something I could get some use out of. My house seems to make enough static electricity in the winter to spin the meter backwards.

@lehighline hopefully I can find something with the same ID and wall thickness. I'm not so sure SCH40 PVC carries the same wall thickness as SCH40 metal pipes. It should carry the same ID though. Regardless, this or Static Guard will surely get me by.

That only leaves the screw I was going to use to move the sand through the pipe. I have to squeeze that pipe through a helix in the track to get it to a coal mine so it won't slope enough for sand to run down it. But maybe the plastic screw won't generate any static. I'm not sure how it that would work. Possibly a metal pipe and then spray the screw with Static guard?


Don't plan on the same wall thickness. Things don't work that way. Plastic piping is always thicker walled than metal for a given ID, at least for common materials and usage. But I'm pretty certain your assumption on the ID is correct.

Bill's thoughts on Static Guard are worth looking at. I don't know if the coating wears off or loses potency. Time will tell.

I'm thinking a homemade metal auger may be better than a plastic one, simply for wear and tear. I suspect the sand is going to be abrasive as heck, especially to plastic. Not exactly certain how to construct one. That's a bit above my pay grade! But you may get some ideas from pictures of stokers or farm equipment. I think augers are used in grain harvesters.



@lehighline I believe you're correct. I think pipe schedule is related to pressure rating. But I haven't had to know any of this stuff in a long time.

I might go with a rotating spring instead of an auger now that you mention it. We use springs as augers at work and it gets the job done.

I haven't had much time to get in the basement and move some coal. The weather has been mild lately so I've been outside landscaping, putting trim on shed, etc, etc. I'll probably update the main layout thread I have when I do find out just how the sand is performing. I also intend to post about the unloader when I get it working better.

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