I bought some 1" smurf tube so that I could run coax, ethernet, and speaker cable to various low voltage outlets in my house. I used a 1-1/4" speedbor bit to make a hole in the floor from my crawl space but discovered that the smurf tube was 1" inner diameter and 1-1/4" outer diameter. Oops. It turns out it is very difficult if not impossible to force the flex tube through the approximately 6" deep hole.
I tried using a file to widen the hole but it had little effect. Should I try widening the hole with a 1-3/8" auger bit, a 1-3/8" spade bit, a sanding drum bit, or something else? There's not a lot of room in the crawl space so I'm hoping to hit upon the solution the next time I go under.