Hose Barb ponderings

At SME, under Garden Hose Fittings, a comparison of hose barb sizes:

Source: SME Industrial Company, Ltd.

I'm thinkin the fractions are the nominal size, and the decimals are the actual OD. For the half-inch barb, for example, the OD is .03 bigger than half an inch, about 1/32 of an inch bigger. So the ID must be less than half an inch, or the piece would have essentially no thickness.

I want to know the IDs.

In particular, a lot of "hose mender" fittings are sold as suitable for either 5/8" or 3/4" hose. Those fittings must be tighter on the 5/8" hose than on the 3/4". So, how big is the fitting relative to the hose ID? How big is the fitting ID? And does anybody make a "bigger" fitting for each size hose? Because if the fitting is big enough that you have to force it into the hose, maybe it is big enough that it doesn't restrict the flow, and maybe the 5% pressure-loss problem would go away.

If the fitting is tight, soaking the end of the hose in hot water for a few seconds will soften it up and the fitting will go in easier.

But apparently they don't make oversize fittings, as the pressure-loss problem hasn't gone away.

Could be the problem is different that I think. Could be the pressure loss results from a disruption of the smoothness of the inside of the hose, and not from the smaller diameter of the fitting. Could be both these factors. If so, then using fittings with a larger diameter would likely reduce the 5% number, meaning less pressure loss from the fittings. That would be an improvement.

All of this is just a guess, at this point.

A one-gallon pressure tank from soda bottles

This is my one-gallon pressure tank, sitting on Maxwell House instant coffee jars:

• Inlet (left) and outlet brass are quick-connect fittings. Inexplicably, I used teflon tape.
• The hose is 5/8" ID, from True Value, pieces cut about 3" long.
• The hose clamps are #8s, less than a buck apiece from Lowes. They don't have long tails, the #8s, on 5/8" hose.
• The tees, 63 cents apiece, from United States Plastic Corporation.
• The white fittings are three female and one male nylon GHT-to-5/8"-hose-barb fittings, from US Plastic Corp. The females came with eye-catching red hose washers.
• The green fitting is a shut-off valve, similar to this one.

No leaks. In particular, no leaks at the soda bottle slash hose fitting connections.

The outlet end hooks up to a garden hose. I've been using a 50-ft shrinky hose, as that's what I had. But 25 feet would be more than enough, as the pressure tank hooks up to a sprayer on a cart, and the tractor moves the cart.

The inlet end hooks up to the sprayer. I cut off the sprayer wand and most of the hose, and used a GHT-to-3/8"-hose-barb fitting to connect sprayer to pressure tank.

It's embarrassing to call the assembly a pressure tank, really. It's too small to be effective. But it was built for test of concept, and it worked. Between uses, the soda bottles sit empty, or rather, full of air. When I hook up the sprayer and turn on the pump, outlet valve closed, the bottles fill with water, compressing the air in the process. It does what I need.

I have a 25-gallon sprayer. With a 20-gallon pressure tank I'll be almost doubling the capacity of the system.  The pump on my sprayer is a low-volume unit that shuts off at 60 PSI. The pressure tank helps to compensate for the low output of the pump and the resulting low average pressure in use.

My one-gallon pressure tank works. But it needs to be bigger to be effective. So I'm saving soda bottles. It would defeat the purpose to go out and buy them.

Soda Bottle to GHT (Garden Hose Thread) Modification

A soda bottle cap easily fits the male end of a garden hose. But the soda bottle won't fit the female end. Soda bottle threads and garden hose threads are similar but not identical.

Soda bottle threads can be easily modified to fit garden hose threads.

By "soda bottle" I mean one- and two-liter bottles that Coke comes in, and Pepsi, and even Schweppes.

By "garden hose threads" I mean the US standard, not the British standard.

Get a cup of hot water, as hot as you'd make it for instant coffee. Dip the soda bottle threads in the hot water for 15 or 20 little alligators, then take it out and screw on a garden hose fitting. Done.


Myself, I'm not a practical person. I'm the kind of person who needs step-by-step instructions, plus hints and tips. But I don't have much of a memory. I make notes on how to do things and what tools to use, and then usually misplace the notes.

I wrote the instructions below originally for my own use, to develop a reliable process, because I want to make a 20-gallon water pressure tank and I'll need to modify a lot of two-liter soda bottles to do it.

Preparing a Bottle

1. Finish the soda. Rinse and save the bottle. Save the cap, too, as it will fit on a garden hose.

2. Cut off the plastic band that once held the cap on the bottle. For this I use my wire cutters -- diagonal-cutting pliers, I guess they're called.

As the Educational Innovations site says, make sure you don't scratch the bottle. A scratch is a weak point, and if you put air or water under pressure in a scratched soda bottle, the bottle may fail: KA-BOOM! Just be careful.

2b. You'll want to take the label off too. It makes your project look so much nicer! Chris Notap says use WD40 to get the glue off the bottle. Works great.

Again, safety: A comment on Notap's video says repeated pressurization and depressurization will weaken the soda bottle, and it will eventually explode. Notap agrees. Maybe this ought to be a conceptual project, not one that actually gets built. Maybe I'll make a cage of hardware cloth for my pressure tank. The safest thing would be not to use soda bottles in pressure applications.

On the other hand, seeing is believing.

3. To modify the threads I use a brass hose nozzle like the "bonus" nozzle shown here, the short one. Brass is good because it is less willing to change shape than the bottle.

The threaded end of my bonus fitting is full of threads. Some fittings don't have much thread at all. More is better.

My bonus fitting is one piece, not a swivel fitting.

3b. If your bonus fitting end has a hose washer in it -- it probably does -- take the washer out. It will get in the way when you are modifying the soda bottle threads. A small screwdriver or an awl will dig the washer out.

4. Start screwing the bonus fitting onto the soda bottle. Take your time with this!!! It will bind almost immediately when you put it on. Don't force it. What's important is to make sure the fitting will go on straight. If it goes on crooked you may ruin the bottle, or the bottle connection may leak, or the bottle may connect at an angle and look funny and your friends will laugh at you.

The threads don't match, so the nozzle wants to go on crooked. Don't let it! Just keep trying till it looks right, then screw it on. Sometimes I do it half a dozen times so I can see what looks good and what doesn't. It won't go on far. Don't force it. Just get it started.

5. Make sure you have your bonus fitting started square on the bottle, not at an angle. Do it over if you're not sure. And only get it started.

6. Get pliers or a wrench or something you can use to tighten the fitting on the bottle. Don't tighten it yet.

7. Put hot water in a coffee cup. Hot like you are making instant coffee. Fill the cup pretty full. The hot water will soften the plastic of the soda bottle enough that tightening the bonus fitting will modify the threads of the bottle. Don't tighten it yet.

8. Make sure you can dip the bottle into the hot water enough to just submerge the bonus fitting. You want the whole fitting in the hot water, and down maybe 1/4" below the surface.

9. With the nozzle in place, hold the bottle in the hot water for 10 or 20 seconds. Then pull it out and tighten the fitting. Take all that you can get easily. Don't force it.

Let me be clear: Push the bottle and your bonus fitting together with some force. But don't force the turning that modifies the threads.

When I did this last year I dipped for 10 seconds, and I could only get a quarter-turn at most. Doing it the other day I dipped for 20 seconds, and the nozzle went all the way on after just one dip. A few seconds extra in the hot water bath seems to make a big difference. Either that or the fussiness about getting the bonus fitting on good and straight really paid off.

If you need to dip more than twice, get new hot water.

When you get the fitting all the way on the bottle, I suggest leaving it on for a few minutes, until the assembly has cooled.

If you test your re-threaded bottle under pressure, be sure you have a way to de-pressurize the thing without hurting yourself. For example, connect a tee fitting (with shutoff valves) to your hose, and screw the bottle into one leg of the tee. You can open the shutoff on the other leg to release the pressure.

Oh -- pressure. I'm only working with 60 or 65 psi max, water pressure. I don't think I'd use soda bottles at higher pressures.

Soda Bottle to 1" PVC adapter

File this one under Miscellaneous Fittings: a "bottle bushing".

From Educational Innovations Inc ("Teachers serving teachers") a plastic fitting and an o-ring for a buck and a quarter:

Finally! An inexpensive and quick way to attach standard soda bottles to PVC piping for use in many STEAM projects such as bottleponic, hydroponic and aquaponic gardens, dispensers, or whatever the imagination can come up with. Made from food grade PVC and includes a food grade O-ring which forms a seal around the neck of the bottle. Fits into any 1 inch Schedule 40 PVC socket fitting.

PVC adhesive required, not included. NOT for pressure applications.

"Not for pressure applications." So I wouldn't want to use it to make a 20-gallon pressure tank out of soda bottles. Interesting nonetheless.

Had to have em

You may remember these fittings. I was drooling over them, the Snip-n-Drip fittings. These are meant for the Snip-n-Drip hose, which is described as half-inch hose.

Really! A lot of soaker hose is 3/8" hose, 3/8" ID.

Okay, the Snip-n-Drip fittings are for half inch hose. I don't generally use half-inch hose or smaller sizes. Could be using it more, though, as I've been thinking about getting soaker hose and setting up permanent ("summer-long") hose layouts. But up till now, no.

Be that as it may, most of my hoses are 5/8" and the Snip-n-Drips won't fit. But I found some that will fit, at ACE. Look just like em:

And look at those prices! The "shipping" is just me, going to get them. But that's not a cost... It's a delight. Even. I. like. shopping. (Don't tell my wife!)

And these are for 5/8" hoses, and 3/4".

Well you know what? Long story short, I bought some. Ordered em from Ace. Should be in in a week. But there is more to the story.

I found the same fittings on Amazon. Of course I did: Jeff Beezos is like Pinky and The Brain, trying to take over the world.

I couldn't buy the Ace fittings, good as those prices are, without first comparing Amazon's prices. Amazon made it complicated by offering different quantities at different prices. I grabbed the price info for

• the female end mender,
• the male end mender, and
• the mid-hose mender

and figured out "each" prices for the different quantities they offer:

	Male End	Mid Hose	Female End
ACE	$2.39	$2.39	$2.39
Amazon Qty 1	$6.99	$5.74	$4.89
Amazon Qty 2	$4.41	$4.23	$4.41
Amazon Qty 5	$3.07	$2.84	$3.06
Amazon Qty 10	$2.68	$2.55	$2.86
Amazon Qty 20	$2.44	$2.39	$2.40
Amazon Links	Male End	Mid Hose	Female End

I had to pay sales tax on the Ace fittings, which brought the price up to $2.59 apiece. I bought five of each, because I could justify that quantity. To beat Ace's price at Amazon I would have had to buy 20 of each, for a total of almost four times what I paid at Ace.


The man who took my order asked, "What are you working on?"

Getting ready for Spring!

"Rubber Wall Base"

I needed some thin rubber strips for a project I was working on a while back, but I had the hardest time finding something satisfactory. Yeah, Home D offers hundreds of options. But I didn't need 24 square feet of the stuff, and I didn't want to pay double digit dollars to get it.

I ended up getting some odd shaped, squishy strip meant for garage doors. It wasn't flat, but I could cut one leg off and used that. It was still wedge-shaped and not as stiff as I wanted, but it was the best I could find.

More recently, I wanted some thin, flat rubber to use as spacers on another project. I had to take the dog to the vet and while waiting for the doctor I was wondering where to get that thin flat rubber. Then my eyes landed on the trim in the doctor's office, between the wall and the floor. Not wood trim: this was some thin stuff four inches high, curved out at the bottom to meet the floor. Is that rubber? I wondered.

That's rubber. Lowes has "Thermoplastic Rubber Wall Base", four inches high, four feet long, less than three dollars apiece. And they have it in black, the color rubber is supposed to be.

Happy camper.

Well that's disappointing

My old house was old. Pipes would spring leaks for no reason. Where I say "no reason" you might say "corrosion", but you get my point. Old house.

The old house had half-inch copper pipe for the water supply. The new house, where I am now, has 3/4-inch pipe. The water flow is way better.

The new house has two outside faucets for my garden hoses, front and back. But you know what? They're both plumbed in half-inch pipe, like some kind of afterthought. What the heck! The one of em is only 6 or 8 feet of half-inch before the spigot, the rest three-quarter. The other one is half-inch pipe, full width of the basement; then it turns the corner and disappears from view, still half-inch.

So much for my plans to change the spigots, to put in ones that you could drop a 3/4" marble through, so to speak. A little additional re-piping will be needed.

I wonder the reason they changed from 3/4 to 1/2 for the outside faucets. Convention? Regulation? Save a buck? Eh, I'm still thinkin three-quarter pipe inside, three-quarter spigots, and three-quarter hose outside before it branches off. Think big.