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Discussion Starter #1
Can anyone tell me approx how far (on average) 18 cu inch of fine ballast would go on an HO layout with 5mm X 1-3/4" trackbed on relatively flat surface?
 

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Well, to me this seems like a math problem, so I will attempt to solve it :eek:

  • 5 mm = 0.1969 in
  • 0.1969 in x 1.75 in x total length of coverage = 18 in3
  • 18 / 1.75 = 10.2857 / 0.1969 = 52.2383 inches of coverage
I will let the HO guys take it from here on out in case I have missed some crucial factor which I have not learned about yet, LOL :retard:
 

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I haven't used that kind of math in 30 years...I just pour it 'til I run out (usually on a Saturday night at 11:30pm:eek: ).
 

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Discussion Starter #4
Ballast

Boston,

I figured this out after my post. You are close I think. Not to beat a dead horse or split hairs, but...Substitute 0.0625" for 0.1969" (1/16" = 0.0625" = depth of track ties) and I came up with 164" +-. But of course this is all theoretical. Not taking into account the angle of repose, individual size of ballast, etc, etc...I could be wrong, I have been before, correct me if I am.

Shaygetz,

Good one.
 

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Substitute 0.0625" for 0.1969" (1/16" = 0.0625" = depth of track ties) and I came up with 164" +-. But of course this is all theoretical. Not taking into account the angle of repose, individual size of ballast, etc, etc...I could be wrong, I have been before, correct me if I am.
That is why I was not sure how accurate my answer was, I do not think I have ever even seen a piece of HO track in person, so I had no clue how thick the ties were... I just used the 5mm you mentioned, not even knowing what is stood for, I just needed that third number for the volume equasion, LOL :)

I also thought about the angle of repose, and for that you would just have to find the area of the trapezoid the ballast formed, but with HO scale I do not think it will make that noticable of a difference... That volume of the ballast would then be [(top width + bottom width) x height / 2] x total length = 18 in3...

But like Shaygetz kind of said though, it will probably be different for everyone since everyone ballasts a little differently...
 

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You guys are forgetting packing density.

OOOOOOOOO
OOOOOOOO
OOOOOOOOO

Packing density for spheres is something like .75 so you would divide your number by .75 and you'll see it'll go further.

Of course you could do what I do and just buy a second bag! :eek:
 

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You guys are forgetting packing density.

OOOOOOOOO
OOOOOOOO
OOOOOOOOO

Packing density for spheres is something like .75 so you would divide your number by .75 and you'll see it'll go further.
Is'nt that already factored into the amount of content printed on the package though, in this case the 18 cubic inches? I always thought that it was, but I am probably wrong though as usual, LOL :eyes:
 
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