Originally Posted by
Irving
The barbs on a 1" press on fitting are about the same size as the outer diameter of the pipe. A 3/4" barb fits on the inside with just a hint of resistance. I like the heat gun idea, but since I'm going to be burying this particular junction again, I'm worried about it a little. My old house has other pipes that are no longer standard sized that I've had to work around, so I'm not exactly surprised and I'm sure my sprinkler system is ancient. Some of the existing fittings (of which I have extras, still in the package) have a copper expander that is pressed into the pipe. I'm wondering if I can find some sort of thin rubber hose that I can stretch over the 3/4" male barbed end, then cram the whole thing into the 7/8" pipe, then seal it all down with a clamp. That is more or less how I solved the issue with an odd sized drum trap under a bathtub. I like the ideas you guys are giving me so far.