I thought that stretching LRT over a barb (namely 1/8" LRT over a 1/2" barb) was the goal here. Killer 7 did get 1/2" tubing onto a 3/4" hose barb with his 'ice cone' method. Although I admit that 1/8" tubing onto a 1/2" barb would be a lot more difficult, if not impossible, but it's the best method we have so far.sbell25, Killer 7's method is designed for stretching LRT over a barb. If we want to slide an entire tube underneath, things become more complicated. But the underlying concept is the same.
While writing this, I just had a thought about another method for stretching LRT over a hose barb. Anyone ever heard of Castration Ring Applicators? They're a form of pliers used to stretch castration rings. For those who don't know, castration rings are very thick rubber o-rings used for castration or tail docking on farms.
If you look at the picture, you'll see the 4 little hooks at the end. The o-ring goes on there, and then when you squeeze the handle they all move away from each other, stretching the o-ring. I remember we had one back in NZ a long time ago, and I'm pretty sure it'd stretch far enough for our purposes. However, I'm not sure whether it'd be powerful enough for LRT, although those o-rings are pretty thick.
I might have to do more research on this.