Tip #19: Get a Straight Cut on a Hose
by Dave Coleman
If you’re the kind of guy who buys things that fit, or builds things from kits, maybe you don’t need to know this. But if you’re the type who would make an intercooler pipe coupler out of radiator hose from a semi, or dig through the hose selection of your auto parts store to find the three hoses that will splice together to connect an L18 water outlet to a Datsun Roadster radiator inlet, then you should be familiar with this trick.
Trimming a hose to length is surprisingly tricky if you actually care what the result looks like. Most giant scissor-like cutters will leave a crooked cut, since the process of crushing the hose between the blades distorts the hose. Freehand cutting with a razor blade usually results in a zig-zag mess, between the flexing of the hose, and your inability to get the blade to come back around to the same place the cut started.
The best technique I’ve found is, as pictured, to simply slip the hose over a pipe of the same diameter and use the pipe to guide your razor blade. Always use a fresh blade, of course, and continuously cut a little bit downward toward the pipe so the cut doesn’t wander away from the guide.
The resulting cut will look about like this. Not quite a factory-quality cut, but pretty close.
Another helpful detail: Measure how much you want to cut off, and then mark the pipe (on both sides!) and slide the hose on the appropriate amount. Second tries never work out well…