Damned Projects! (2025 Update)

I generally like to nail this sort of problem to the floor, e.g. by buying better quality drain hose, such as braid-reinforced silicone.

My washing machine is in the basement, so a bit of water on the floor is no big deal.

Cheers

Phil Hobbs

Tell us about your design.

I recall a water detector made from a clothespin and an aspirin and a couple of pieces of wire.

But it doesn't take much current to turn on a mosfet.

True, and that's what my design relies on. I say "design" but that's over-dignifying it. I doubt there's more than 10 components to it all told - tops! Still, the most important thing is it works. How did the pin/aspirin desgin work??

The last time my hot-water tank pin-holed through and spread water all over the floor, the plumber that replaced the tank put a shallow water-catching tray underneath the new tank and put a battery-operated stop valve into the cold water feed. The stop valve can with a water sensor that sat in the tray, and turns off the cold water feed if there water in the tray.

It's one more thing that screams at me when it's batteries get close to running out, but that's less of a pain than a lot of water wrecking the carpet, or the parquet that replaced it.

Talk to your local plumbing supplier - it's madness to waste time on design when you can buy something off the shelf.

It's called getting old bro

Why only cut off the power? Surely the important thing to do is cut off the water supply. Something like this should do it:

That would also serve in the (admittedly rare) situation where the water supply tubing to the washing machine fails.

Ingenious!

Just for a bit of fun (which I don't get much of at my age) I thought I'd replicate the idea to see how effective it is. My first attempt didn't work out at all, as the clothes peg compressed the (soluable) aspirin as it became saturated and prevented it dissolving sufficiently for the gap to close. I was left with about a tenth of an inch between contacts.so FAIL! For this to stand any chance of working, you'd have to fashion the contacts so they have pointy ends. That should work, BUT if it were used in my applcation, several dozen gallons of water would be all over the floor before it would be able to close-up. My design, OTOH, shuts off the electric in about 25 femto-seconds. :-)

Madness in Art: A Powerful Connection

Madness and art have long shared a profound and powerful connection, where the boundaries between genius and instability often blur. ...

The art of электроника: why not create a DIY water alarm with the venerable 555?

Electrolysis can cause the DC sensor to degrade over time. An analog adaptation from resistance to capacitance can curb this effect. The above sensor needs to be altered to detect a dielectric difference instead of an ohmic resistance.

Danke,

The sensor I made is simple and reliable. Etch a board with two "combs" where the tines of the combs interlace, like this:

When water drips onto the sensor, the open circuit between top and bottom "combs" goes to a resistance, in my case below

Ed

Perhaps spme sort of adaptation of my conductivity meter circuit would do the job:

It generates floating AC with prevents electrolysis at the sensor and uses synchronous rectification to eliminate spurious responses. For simplicity, the range switch could be replaced by a pot and the meter drivers arranged to switch a relay.

Asprin tablets contain a large amount of compressed chalk, which doesn't dissolve. You need to find something that dissolves completely like a sugary sweet or even a sugar cube. During WWII, indigestion tablets were used to delay the release of floating mines from a river bed, but they also contain chalk and wouldn't work in the 'clothespeg' device..

Dishwasher salt tablets would work but may become too conductive if the local humidity was high - they would also corrode the electrodes. I was in some very damp rented accommodation once and I accidentally spilled some salt on the kitchen worktop one evening; when I looked the next morning it had turned into a salty puddle.

Yes, salt is massively hygroscopic, giving it another attack vector against steel-bodied cars even if it hasn't been raining. I believe it doesn't agree at all well with slugs, either!

The way I've seen water detectors done is with an LED angled to reflect off a piece of glass to a photodiode when the glass is dry. When the glass is wet the index of refraction of the glass/water is different from the glass/air and allows the light to pass through and not hit the photodiode. That's how automatic windshield wiper raindrop detectors work.

I'm wondering about removing the washer intake valve from the washer and hard connecting it to the supply. No hoses. Then only one hose goes from the valve output to the washer and it only has water in it when the washer is filling.

PS: Braided stainless steel isn't water tight. From what I've read what's inside and how the ends are crimped is more important. How long do real hydraulic hoses last? They don't have a stainless outer braid.

here some thing like this:

No filter either. The smallest piece of dirt can jam a valve open.