My Quest for a Decent Car Wash Wand Soap Dispenser

So, I got fed up. Real fed up. You know those car wash places, the self-serve ones? Their soap is... well, let's just say it's not exactly premium stuff. And half the time, the soap setting on their wands barely spits out a few sad bubbles. I figured, I can do better. Or at least, I can make something that uses my good soap.

My first thought was, how hard can it be? Water goes in, soap gets mixed, foamy goodness comes out. Right? Yeah, well, like most of my brilliant ideas, it started simple and then, you know, life happened. I wasn't looking to build some fancy, store-bought looking thing. Just something that worked, something I could say I put together myself.

Figuring Out the Guts

I wasn't about to reinvent the wheel, or in this case, the venturi injector. That's the little gizmo that sucks soap into the water stream. I poked around my garage, looked at some old plumbing bits I had lying around. I’m more of a "see what I've got and make it work" kind of guy, not one to run to the store for every little thing.

My initial pile of potential parts included:

• Some clear tubing I salvaged from an old fish tank pump. Good to see if soap's actually moving.
• An old, sturdy plastic shampoo bottle. Seemed about the right size for the soap.
• A brass T-connector I found in my box of miscellaneous plumbing fittings. This looked promising for the mixing part.
• A handful of hose clamps of various sizes – you always need these.
• An old garden hose nozzle, the cheap yellow plastic kind.

The "Assembly" - Round One, More Like a Wet Fiasco

Okay, "assembly" is a mighty fine word for what actually went down. It was more like an hour of me getting soaked while muttering to myself. I hooked up the T-connector to a short bit of hose, then the nozzle. The side arm of the 'T' got the clear tube, which I jammed into the shampoo bottle full of my car soap.

Turned on the tap. Water shot out the nozzle, alright. But soap? Not a drop. The tube just sat there, full of soap, mocking me. Turns out, just sticking a tube into a T-connector doesn't magically create suction. Who knew? Probably should've paid more attention in science class, but there you go.

Back to the Drawing Board (Which is Actually My Stained Garage Workbench)

I needed that suction. I remembered some sprayers use a narrow point to speed up water and drop the pressure. I rummaged through my fittings again and found a reducer, a piece that went from a wider diameter to a smaller one. I jammed this into the T-connector, right before where the soap tube connected. The idea was to make the water hustle past that soap tube opening.

Attempt Number Two: A Glimmer, Then a Dribble

Connected everything again. More carefully this time, trying to avoid another shower. Turned the water on slowly. And hey! Bubbles in the soap tube! It was actually drawing soap! I cranked the water up a bit more. The soap moved faster... for a second. Then it kind of sputtered. I got a weak, soapy stream, but nothing you'd call "foam." And the pressure out of the nozzle was pretty pathetic now because of my reducer "choking" the flow.

It was also super sensitive to where the soap bottle was. If it wasn't held just so, slightly above the T-connector, the soap wouldn't flow. This wasn't going to be very practical for washing a whole car.

The "Good Enough" Moment Arrives

I was about ready to give up and just go buy one of those fancy foam cannons. But I'm stubborn. I took another look at that cheap garden nozzle. It had a little dial to supposedly mix in fertilizer from a tiny attached bottle it didn't come with. The hole for that was tiny.

So, new approach: I ditched the T-connector for a moment. I took a simple brass hose mender – just a straight piece to join two hoses. I very carefully drilled a small hole in its side. Then I took a small brass nipple fitting, the kind with threads on one end and a barb on the other for a tube, and managed to thread it into the hole I drilled. Used a bit of pipe sealant to try and make it hold.

The soap tube from my shampoo bottle went onto this barbed nipple. The hose mender then went between my short "wand" hose and the spray nozzle. The theory was the same: water rushing past the little hole would pull soap in. No fancy reducers to kill my pressure this time, just a small, hopefully effective, tap-in point.

Testing the "Final" (For Now) Contraption

Hooked it all up. Held my breath. Turned on the water.

And it worked! Well, it worked enough. It wasn't a blizzard of foam, more like a decent stream of soapy water. But the soap was mixing, and I still had good pressure from the nozzle. I found if I used a nozzle setting that made a wider, more aerated spray, it kind of foamed up a bit when it hit the car. Good enough for me!

What I Ended Up With, And Why I Bothered

So, what I've got now isn't going to win any design awards. It’s a bit rough around the edges. It’s my shampoo bottle soap dispenser car wash wand. Sometimes the tube needs a wiggle. But it uses my soap, and it cost me basically nothing except an afternoon of tinkering and getting a bit wet.

Every time I wash the car with it, I get a little kick out of it. It’s not perfect, but it’s mine. And it’s a heck of a lot better than the sad excuse for soap I was getting at the coin-op. Plus, I didn't have to buy some overpriced plastic thing from a catalog. Maybe one day I'll try to make it foamier, but for now, this little project is chalked up as a win in my book.