Famous Reading Anthracite Coal - 28.5 cu in

[Arthur P. Bloom]

She's a WITCH!

[webenda]

including the air space

Perhaps this variable is one to consider? How irregular particles pack might change the amount of air space?

Packages of graded sizes of coal have the same voidage (fraction of free space) after every pour. Airspace is not a variable.

Vibration reduces voidage if the particles are irregular in shape.

Dennis's correspondence indicates he does not shake the pour. I shook mine an attempt to level the surface in the measuring cup. Not shaking vs. shaking may be why I measured a smaller volume than Dennis. OK--airspace is a variable in this case.

Thank you Rufus.

[Rufus T. Firefly]

including the air space

Perhaps this variable is one to consider? How irregular particles pack might change the amount of air space?

Packages of graded sizes of coal have the same voidage (fraction of free space) after every pour. Airspace is not a variable.

Vibration reduces voidage if the particles are irregular in shape.

Dennis's correspondence indicates he does not shake the pour. I shook mine an attempt to level the surface in the measuring cup. Not shaking vs. shaking may be why I measured a smaller volume than Dennis. OK--airspace is a variable in this case.

Thank you Rufus.

It just reminded my old physical chem experiments on partial molar volume . Also, when I'm pouring RTV or resin and use the drier to rest the pour on to give it a bit of a shake.....

[rogruth]

There is some important information in this topic but the most important thing is IMHO that Wayne is having FUN
by combining his old profession with his model train hobby. Way to go.

[Mitch]

Ya wonder why there's little participation about trains on this forum? All this (is this really a word?) ANAL ity about the volume of a bag of coal with expensive testing equipment also brought in, just to prove Dennis a liar in his product information? Rock on with OCD.

[Roy]

Ya wonder why there's little participation about trains on this forum? All this (is this really a word?) ANAL ity about the volume of a bag of coal with expensive testing equipment also brought in, just to prove Dennis a liar in his product information? Rock on with OCD.

I don't believe this is about proving anyone a liar. It's about Wayne's scientific curiosity.

Do you have any models you've finished lately? I'd like to see them.

[webenda]

I used the "proper" method (i.e. overfilling a dry measure cup then scraping the overfill off) and got 28.5 cu in per bag.
It is now 1:33 AM in Tucson. I am going to bed. When I get time I will repeat the measurement and post photos.

[webenda]

Dennis's response:

Dennis Brennan
9:18 AM (2 hours ago)

To: Wayne

Wayne, it's not a problem. No apologies necessary. This has been funny and enlightening at the same time. However, now I am curious as to how I arrived at 28.5 using my method. A typo coincidence? I would never intentionally inflate a number but now it appears it's accurate. I think you know that I try to be precise in everything I do. If it wasn't a brain fart, I haven't a clue as to how I measured it.

Merry Christmas and thanks for the PR.

Dennis