coal bin auger placement

I have two coal bins in my cellar one 8 by 11 that feeds my AA 260 and one the oppisite wall a 8 by 8
neihor has a sloped bottom I ordered a 4inch 3/4 hp 17 foot auger so I can fill the coal bin on the driveway side 8 by 8 and transfer it to the larger bin with out driving over the lawn.
I plan on building a dog house in the new bin.
Would it make much diffrence in the auger is in the middle or closer to one side?
If I put it in the middle the auger would be above the 260
ordered a 8 foot flex hose to direct the coal into the fed bin.
ok what did i forget????


Screw bottom will be Feed Shute will be 5 .5 feet in the air.
I have 12 ton comming
BLACKDIAMONDDOUG

Can you post a few pics or a sketch? It sounds like you are hoping to empty each bin using an auger in one place. I'm afraid you are going to be doing a lot of shoveling to keep the auger covered with fresh coal.

My coal bin is 4 1/4 feet by 9' by 8 feet tall. My AA auger is slightly off center and it makes a big difference toward the end of the season. If I had realized I may have designed the place such that it could have been dead center. As mine get's close to the bottom I have to rake it over. 5 seconds a week for the last ton.

If they don't have sloped bottoms, the angle of repose will take over. Typically, you will have a "hill" of coal at about a 35 deg. angle. It will be +/- 5 degrees depending on coal size. In any position, you will not be able to get all of the coal without raking over the auger when it gets low.

What is the minimum slope for the walls in order for the coal to reliably run down hill to the auger on its own?

Pea coal. I have a few doors that I use to hoe to the auger.
ok so ill put the auger as close to the middle as possible pictures when auger is in the house. Thanks

lsayre wrote:What is the minimum slope for the walls in order for the coal to reliably run down hill to the auger on its own?

35 degrees +/- depending on coal size and the coefficient of friction of the bottom. I would make sides at 45 degrees to be safe. This would ensure a clean dump of the coal bin.

Attached are plans for a fertilizer bin I found on the internet. It would make a interesting coal bin with a little more elevation. The sides are at a 45 degree angle. Powdered fertilizer has a angle of repose of about 40 degrees.

Here is another neat bin for grain. It would hold a lot of coal but it was designed for grain at 30 lbs per cu. ft. and coal is more like 50 lbs. per cu. ft. Perhaps making it shorter would prevent overloading. Its sides are at 54 degrees to ensure complete cleanout.