I'm thinkin of drilling thorifice to fit a regular gas dip tube. I've noticed that it's not the entire hole that is too small. A normal tube fits for about the first half, and then it tapers down. I think I can bore it out. Anyone see any problems with this?
Obviously I need to make sure the finish hole is smooth as to prevent crevices for bacterial growth.
Yes. The plastic dip tubes are a smaller outer diameter than the stainless ones. That flange is less than 1/16th of an inch thick it doesn't really put much additional pressure on the spring. If your keg doesn't seal without the dip tube you could toss in a stainless washer, but mine work fine without anything.