Compressed Air Routed Through the Floor
As it turned out there is about 18 inches between the floor of the train room and the ceiling of the garage which meant a second trip to Home Depot for a LONG bit and then a third trip for a bit extension. I do feel better about the house knowing how much insulation there is around the garage!
Also it seems that the width of the wall of the garage is wider that the width of the wall of the train room. The first hole, and the second hole we drilled down from the train room ended up in the wall of the garage. At last, the third hole drilled about six inches from the side wall of the train room landed in the garage! The hose fit snugly to the bit extension and was easily pulled through the floor into the garage. Success at last!
The entrance in the garage ceiling is nothing spectacular. It is directly over some wall-mounted shelves, also camouflaging the air line's entrance into the garage. This hose was fitted with male Quick-Connect fittings at both ends. The air tank valve and the air compressor hose are now both fitted with female Quick-Connect fittings so that when disconnected, the air in both the air tank and the compressor will be bottled.