After hours of explaining exactly why this was so important, my wife agreed that I should do it. Well, actually, that didn't happen. I explained it to her, and she looked at me like I have two heads, and quietly accepted that I was going to do it anyway.
This is a preliminary build of the cylinder, just as a proof-of-concept. I built it to be able to be disassembled (nothing is permanently glued). I had thought that this might make the final product weaker, but it turned out to be stronger than I had anticipated. I may end up using this method to build the final one that matches the size requirements, so that I can re-use as many of the parts as possible if the need arises.
For this build, there are a few parts that are must-haves, but everything else was cobbled together from what I had kicking around in the garage. Feel free to modify, substitute, and improvise if you're going to build one yourself.
Step 1: Materials
Here's a short list. There are probably some things I neglected to write down, but they're the sort of things that you've likely got already.
- A length of 2" ABS pipe (I used 2 feet)
- A similar length of 1 1/2" ABS pipe (it's not pictured, but I cut a 2' piece off some leftover pipe I had in the garage)
- A 2" inspection end cap and plug (it's a threaded end cap that can be opened if necessary)
- A 1 1/2" end cap (not threaded)
- A 2" to 1 1/2" reducer
- A large O-ring (mine came from a pool hose fitting)
- Teflon tape
- A solenoid valve. I scavenged mine from a defunct dishwasher, but I suspect a sprinkler valve would work in a pinch). Make sure you keep the wiring harness connector for the valve. It will make your life easier.
- Various fittings to make things fit together
- Some hose clamps for good luck
- Compressor quick-connect fitting
- nylon zip ties
- electrical tape
- "Peel'n'Seal" type removable caulking (mine was Draft Attack)
- Small screw or bolt
- scrap power cord cut from an old appliance
- probably some other stuff that I just picked up off the workbench (like a short length of hose, a net to fit the small screw, and so on)
- saw to cut pipe
- air compressor (the bigger the better, but a small one should be able to operate this too)
- sand paper
- heat shrink tubing (optional)
- pliers, vice-grips, and/or a bench vise
- power bar with switch
Because I had most of the stuff I needed already, this project cost me in the neighbourhood of $15. If you're starting from scratch, I would guess that it would run around $50 with the valve and stuff, and much more if you need a compressor. If you don't have a compressor, you might want to get one. They're loads of fun!