It’s 10:34PM and you’ve just run out of water displacement formula #40. You could wait until tomorrow to get a new can, or you could spend the rest of the night turning an old, empty fire extinguisher into a refillable and re-pressurizable WD-40 dispenser like [liquidhandwash] did. The part count is pretty low, but it’s awfully specific.
And the emphasis is on empty extinguisher. Part of the deal involves twisting the gauge off, and we wouldn’t want you to get blasted in the face with any last gasps of high-powered firefighting foam. In order to make the thing re-pressurizable, [liquidhandwash] stripped all the rubber from a tire valve and removed the core temporarily so it could be soldered into the fitting where the gauge was. The handy hose is from a large can of WD-40, which is also where the label came from — since it’s no longer a fire extinguisher, it needs to stop bearing resemblance to one, so [liquidhandwash] removed the sticker, painted it blue, and glued the cut-open can to the outside.
To use it, [liquidhandwash] fills it up about halfway and then pressurizes it through the tire valve with a bike pump or compressor. (We think we’d go with bike pump.) Since [liquidhandwash] goes through so much lubricant, now, they can just buy it by the gallon and keep refilling the extinguisher.
Is WD-40 your everything hammer? Variety is the spice of shop life.
To those who choose to overclock their PCs, it’s often a “no expense spared” deal. Fancy heat sinks, complicated liquid cooling setups, and cool clear cases to show off all the expensive guts are all part of the charm. But not everyone’s pockets are deep enough for off-the-shelf parts, so experimentation with cheaper, alternatives, like using an automotive fuel pump to move the cooling liquid, seems like a good idea. In practice — not so much.
The first thing we thought of when we saw the title of [BoltzBrain]’s video was a long-ago warning from a mechanic to never run out of gas in a fuel-injected car. It turns out that the gasoline acts as a coolant and lubricant for the electric pump, and running the tank dry with the power still applied to the pump quickly burns it out. So while [BoltzBrain] expected to see corrosion on the brushes from his use of water as a working fluid, we expected to see seized bearings as the root cause failure. Looks like we were wrong: at about the 6:30 mark, you can see clear signs of corrosion on the copper wires connecting to the brushes. It almost looks like the Dremel tool cut the wire, but that green copper oxide is the giveaway. We suspect the bearings aren’t in great shape, either, but that’s probably secondary to the wires corroding.
Whatever the root cause, it’s an interesting tour inside a common part, and the level of engineering needed to build a brushed motor that runs bathed in a highly flammable fluid is pretty impressive. We liked the axial arrangement of the brushes and commutator especially. We wonder if fuel pumps could still serve as a PC cooler — perhaps changing to a dielectric fluid would do the trick.
Continue reading “Fail Of The Week: How Not To Watercool A PC”
On the face of it, keeping fluids contained seems like a simple job. Your fridge alone probably has a dozen or more trivial examples of liquids being successfully kept where they belong, whether it’s the plastic lid on last night’s leftovers or the top on the jug of milk. But deeper down in the bowels of the fridge, like inside the compressor or where the water line for the icemaker is attached, are more complex and interesting mechanisms for keeping fluids contained. That’s the job of seals, the next topic in our series on mechanisms.
Continue reading “Mechanisms: Mechanical Seals”
They lie at the heart of every fidget spinner and in every motor that runs our lives, from the steppers in a 3D printer to the hundreds in every car engine. They can be as simple as a lubricated bushing or as complicated as the roller bearing in a car axle. Bearings are at work every day for us, directing forces and reducing friction, and understanding them is important to getting stuff done with rotating mechanisms.
Continue reading “Mechanisms: Bearings”
If your shop is anything like mine, you’ve got a large selection of colorful cans claiming to contain the best and absolutely only lubricant you’ll ever need. I’ve been sucked in by the marketing more times than I care to admit, hoping that the next product will really set itself apart from the others and magically unstick all the stuck stuff in my mechanical life. It never happens, though, and in the end I generally find myself reaching for the familiar blue and yellow can of WD-40 for just about every job.
Continue reading “Beyond WD-40: Lubes For The Home Shop”