So, after a few weeks the brass fittings I ordered arrived, then work got stupid busy and I didn't have a chance to look at it until this week.
I bought a new extinguisher and let the old one off in the back yard. The dust goes EVERYWHERE, but the neighbours didn't complain, even though their washing was still on the line
. Don't dump it in one spot either, it kills the grass. Should be spectacular when I mow tomorrow for the first time since.
The valve came out of the top of the extinguisher with no issues, but finding a nipple to screw in proved next to impossible. Hardware stores had nothing, plumbing store had nothing, engineering supplied shop had nothing... but they did have a 1/4" BSP tap and 1/4" BSP fittings are easy to come by, so I cut the top off the extinguisher valve head, squared it up in the lathe and tapped it for 1/4" BSP. Issues then were only that there was a 1mm hole that vented into where the extinguisher pressure gauge mounted and that there was not much thickness in the head where the tap cut through. I sorted that by screwing in a hose fitting and soldering it in place with a heap of soldier. Hole filled and valve head now 12mm thick, not 3mm.
2 wins in a row:).
If it didn't work I had the gas cylinder option, but I get to keep it in reserve.
The extinguisher got a coat of yellow to try and keep the colour theme going. Colour is a bit off, but near enough. I managed to get more runs than Bradman, but most are on the bottom and its hidden by the mounting bracket.
All the plumbing was cobbled together for several trial runs before I settled on the setup. I tried the pressure switch closer to the cylinder, but figured if I mounted it in a box, then tools could rattle down there and I didn't want it shorting, so I kept it up high and it will be close to the relay.
For the On/Off switch, the one on the compressor is a bit hard to access now and the air fittings near it are likely to be hot, so I have a spare push button switch that came with a light bar, so will put that to good use. The rest of the lightbar wiring kit will probably get used for this as well.
The other job is a box to put it all in. I started done of those, but stuffed up and made it a bit too wide. I figured I'd live with it as I'll have room for tyre plug gear as well as the hoses. I could probably fit the gas cylinder if I wanted to upgrade the storage too.
The male Nitto fitting will probably get swapped for a female too.
Now I sit down and run a tally, doing things on the cheap isn't that cheap. I bought some brass fittings on eBay, but they weren't the best, so had to go to the big red hammer shop. I got some rubber seal for the box and priced the latches
, I'm sure I had some I pulled out of the scrap bin stashed in the shed somewhere, might have to look harder.
$30 assorted brass bits
$20 extinguisher (old one was 10 years old, so probably due for retirement anyway)
$12 yellow paint
$14 rubber seal
Its all adding up.