Confusion About G1/4 Fittings

[Jeff R 1]

The above is the inside of a 1/4 inch barb fitting, as you can see the hole on the barb looks to be 1/4 inch and the G1/4 end looks to be about 10mm (so I Googled and found references to this size 10mm size)



The fitting on the left is an actual G1/4 adapter I got from my local hydraulics shop (the adapter is 3/8 NPT on the other end)
The ID of the G1/4 is 1/4 inch... No surprises there.

So the people who manufacture our fittings are drilling out the 1/4 inch ID to 10mm ???

Could someone here please measure the ID of one of the G1/4 fittings for me _ I couldn't find any reference to the ID at all ?
Just the major and minor diameter of the threads.

That's the other thing, if the water cooling fittings are being made to 10mm diameter and according to the WiKi, the minor diameter is 11.445, that leaves only .7225 of a mm of wall thickness of the fitting _ not much...

http://en.wikipedia.org/wiki/British_Standard_Pipe

[Hooded]

G¼ is the thread size and has nothing to do with the diameter of the hole drilled through the center. The diameter of the bore will change according to fitting size, style and manufacturer of particular fitting.

[Jeff R 1]

Hmmm...
OK, thanks.
It's odd how a fitting is developed (G1/4) and there are specific sizes for the thread (55 degree pitch) number of threads and major and minor diameter... etc.
And yet no standard for the hole size inside the fitting.
A manufacturer can machine the whole to what ever size is desired I guess.

I'll post some pics what I intend to do to save some money...

[Hooded]

Consider the different requirements for fittings. A stop plug requires a proper matching G¼ thread without a hole. Hydraulic systems see much higher pressures then cooling systems so a thicker wall is required to handle the pressure. Many reasons for the bore size to change.

[Jeff R 1]

Thanks Hooded _ that makes sense.



The koolance fittings are quite pricey, so what I plan on doing is getting a G1/4 split die and changing the threads on the 1/4 inch NPT on the fitting on then right.
I'll have to make up some custom washers and solder them in place to provide a seat for the "O" ring.
I was going to use 1/2 OD copper tube, but I am now leaning toward 3/8 as it will be easier to fit it in my smaller ATX case.
That will provide an ID of approximately 5/16 _ big enough.
The fitting on the left is G1/4 and I think changing the thread on the 1/4 NPT may work as it has enough material to change it to the slightly smaller G1/4.

Anyways I'm going to find out _ should work _ there's only one thread per inch difference and only 2 or 3 threads on most of the commercial fittings are used anyway.
By the time the die "cross threads", the new threads will be formed.

I also want the fittings black and the brass will hold the paint better then the very shiny nickel fittings from Koolance.

One more thing _ the Koolance fittings are 12 bucks as apposed to the 3.00$ ones from the hydraulic store.

[Jeff R 1]

Hunting down a G1/4 split die has become quite the project, if I find a cheap one, the they want way too much shipping _ imagine 43 euros to ship that little thing out of Germany !

The US isn't any better, a seller from New York wants 40 buck to ship !

Spaenaur of Canada wants 73 dollars for the die _ don't know how much shipping is though. Plus the fact it's just a chaser nut, not a proper split die...

I can order cheap crap from China, but I've come across that garbage before _ those cheap dies don't cut threads, they chew them up.

I found a full set of taps and dies in England for 3£, but seriously, how good can the quality be for that.

I think in the end it will be better just to drop the cash for the proper Koolance fittings.

[Fritz_Bodo]

I have a related question pertaining to G1/4. Im new to watercooling and live in the US. I went into a plumbing supply store here the other day in the attempt to find compression fittings to fit my G1/4 threaded radiators. Was hoping to be able to use real plumbing type compression fittings with copper ferrules/olives. I noticed what was sold here was what they call 'pipe thread' which I believe refers to: http://en.wikipedia.org/wiki/National_pipe_thread

Does G1/4 fitting refer to British standard pipe? http://en.wikipedia.org/wiki/British_Standard_Pipe

Why dont we see people using more standard plumbing fittings with copper pipe in builds? I mean if it holds up in your house for 40+ years what is the chance it is going to leak in your build or that you would ever need to check it or retighten a fitting.... Seems like if you could get away with standard plumbing parts it would save a lot of money as well. Though not everyone would want the looks I'd imagine. Is there something I'm missing? Why dont we see a plumbing supply section on the dazmode store? Shouldn't real men use copper ferrules and not plastic o-rings... lol.... What am I missing here?

Thanks

[Fritz_Bodo]

In other words how the heck do I figure out what is G1/4 from a website such as this: http://www.discounthydraulichose.com...tings_s/94.htm

[Hooded]

Most hydrualic fittings will have a longer thread than your standard watercooling fittings. Also they contain a thicker wall with a small hole to better handle the high pressure that is seen in hydrualic systems.

G¼ comes from the gas industry fittings. G¼ is also known as ¼" Britsh Striaght(Standard) Pipe Thread 19 threads per inch. Or ¼" ISO Pipe Thread 19 threads per inch.

Watercooling fittings generally have a much shorter thread sticking out from fitting around 3mm to 5mm long depending on manufacturer and age of fittings. Also have a larger hole to allow a larger volume of fuild to pass through the fitting. More volume is better for cooling loops.

You would find compression fittings if you were to check with a supplier of Natural Gas fittings. These still won't have the same volume as the watercooling fittings have.

[Jeff R 1]

What you're looking at is a standard ferrule fitting that was once a 1/4 inch pipe thread on the end.
I converted it to G1/4 with a split die. It worked well because it was going from 18 threads per inch to 19 TPI _ not much difference.
There was plenty of brass for the die to bite into as well, the NPT fitting is tapered of course and is fatter closest to the base, so when running the G1/4 die over it, there was lots of meat to change from 1/4 inch NPT to G1/4.

The down side is there is no place for the "O" ring to seat, so I will have to make a custom washer and solder it to the base of the thread to give it a place to "seat".

I will also be shortening the length of the thread as well.

Here is the equivalent from Koolance.

http://koolance.com/nozzle-single-fo...ft-copper-pipe

I was planning on going with 1/2 OD copper tubing, but I am going with 3/8 instead.

I changed because after I got my Aquacomputer CPU water block the inlet was about the same size as the ID of the 3/8 tubing, so using a large tube size made no sense to me when the bottle neck was the water block _ why not keep it all the same size.

Here's a guy here who went with 3/8 OD tubing.

Witchdoctor, post 38.

http://forums.extremeoverclocking.co...=368081&page=2

He was confused too, he thought that G1/4 referred to the ID of BSPP, so he went with 3/8 OD pipe.

There are these fittings too that James Walt will be using, post 25...

http://www.dazmode.com/_forum/showth...OME-quot/page3

[Hooded]

In other words how the heck do I figure out what is G1/4 from a website such as this: http://www.discounthydraulichose.com...tings_s/94.htm

http://www.discounthydraulichose.com...x=0&Search.y=0
Did a site search using "1/4 BSPP"

G¼ = ¼"British Standard Pipe Parallel = ¼"BSPP

[Izerous]

Side note Koolance fittings are very short threaded and a few of their products will only accept short threading. Fittings with long threading will bottom out before the o-ring is seated. Other manufacturers are similar, but chances are any hydrolic fittings you get the threading will be far too long as the pressure requirements as noted about the bore diameter are higher so more threads in the block are necessary.