I am thinking about building a coal bin in my cellar next to my EFM to be installed boiler and have the auger feed from that bin. No one in my area sells bulk coal to chute it into my proposed bin thru a cellar window. Looks like I will have to fill 5 gallon buckets and chute it in myself. I am looking for something to use as a chute, nothing more than two feet long on either side of the window since the proposed bin is directly underneath the cellar window. Any ideas? If I build a chute myself, any ideas on its design?