Overclock.net › Forums › Cooling › Water Cooling › 3/8 NPT thread vs. G1/4" thread - Whats the difference??
New Posts  All Forums:Forum Nav:

3/8 NPT thread vs. G1/4" thread - Whats the difference??

post #1 of 7
Thread Starter 
I'm looking at getting a Res. that has 3/8 NPT threads. All of my other WCing parts are G1/4" threads, whats the difference?? Im assuming my G1/4" fittings won't fit the 3/8 NPT thread??
My *Virgin* HTPC
(13 items)
 
  
CPUMotherboardGraphicsRAM
Athlon X2 Brisbane 1.9GHz Foxconn A7GM-S 780G mATX Radeon HD 3200 2GB Kingston DDR2-800 (2x1gb) 
Hard DriveOptical DriveOSMonitor
300GB Sata I (soon to add more) Lite-On Blu-ray/DVD burner Vista Ultimate x64 24" Dell S2409Wb 
KeyboardPowerCaseMouse
Logitech G15 v2 Rosewill Stallion series 400-watt SilverStone SuGo mATX (black) Logitech G5 v2 
  hide details  
Reply
My *Virgin* HTPC
(13 items)
 
  
CPUMotherboardGraphicsRAM
Athlon X2 Brisbane 1.9GHz Foxconn A7GM-S 780G mATX Radeon HD 3200 2GB Kingston DDR2-800 (2x1gb) 
Hard DriveOptical DriveOSMonitor
300GB Sata I (soon to add more) Lite-On Blu-ray/DVD burner Vista Ultimate x64 24" Dell S2409Wb 
KeyboardPowerCaseMouse
Logitech G15 v2 Rosewill Stallion series 400-watt SilverStone SuGo mATX (black) Logitech G5 v2 
  hide details  
Reply
post #2 of 7
No they won't fit without adapters. Almost all WC companies are moving to G1/4". The difference is the threading obviously.
New Rig
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom 9950 125w @ 3.01ghz ASUS M3A79-T Deluxe XFX 5770 1GB 4GB (2x2GB) Mushkin Redline @ 5-5-5-12 DDR21066 
Hard DriveOptical DriveOSMonitor
2x WD Caviar Black 640gb AALS Samsung SATA DVD Burner Windows 7 Ultimate x64 Acer H233H 23" 1080P Monitor 
KeyboardPowerCaseMouse
G15 v2 Corsair TX750 750w Antec 902 Razer Mamba 
Mouse Pad
fUnc Archetype Surface 1030 
  hide details  
Reply
New Rig
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom 9950 125w @ 3.01ghz ASUS M3A79-T Deluxe XFX 5770 1GB 4GB (2x2GB) Mushkin Redline @ 5-5-5-12 DDR21066 
Hard DriveOptical DriveOSMonitor
2x WD Caviar Black 640gb AALS Samsung SATA DVD Burner Windows 7 Ultimate x64 Acer H233H 23" 1080P Monitor 
KeyboardPowerCaseMouse
G15 v2 Corsair TX750 750w Antec 902 Razer Mamba 
Mouse Pad
fUnc Archetype Surface 1030 
  hide details  
Reply
post #3 of 7
Technically speaking, there are a few differences:

1. NPT (in general) is a tapered thread, hence the T. It seals as the barb is screwed in and requires friction between the threads to seal properly. Generally, this is achieved by using teflon tape to ensure the threads slide properly between each other and seal.

2. G1/4 is a straight thread (no tapering). This type does NOT seal in the threads, which is why you ALWAYS see G1/4 barbs with an o-ring. The o-ring provides the seal between the barb and threading. This thread type is easier to use because it provides a much more consistent seal when compared to NPT. I'm not surprised it has become (essentially) a watercooling industry standard.
Burning Phoenix
(13 items)
 
  
CPUMotherboardGraphicsRAM
Intel Q9550 Gigabyte EP45-UD3P eVGA GTX 260 Core 216 SuperClocked 4GB G.Skill DDR2-1000 5-5-5-15 
Hard DriveOptical DriveOSMonitor
3 WD 80GB RAID0, Seagate 500GB, WD 1TB Caviar BLCK Lite-On LH-20A1S Windoze 7 Professional Dual Dell E207WFP 20.1" Widescreen LCD's 
KeyboardPowerCaseMouse
Logitech G15 Silverstone OP750 Lian-Li PC-A10B Logitech G5 
Mouse Pad
Harley Davidson 
  hide details  
Reply
Burning Phoenix
(13 items)
 
  
CPUMotherboardGraphicsRAM
Intel Q9550 Gigabyte EP45-UD3P eVGA GTX 260 Core 216 SuperClocked 4GB G.Skill DDR2-1000 5-5-5-15 
Hard DriveOptical DriveOSMonitor
3 WD 80GB RAID0, Seagate 500GB, WD 1TB Caviar BLCK Lite-On LH-20A1S Windoze 7 Professional Dual Dell E207WFP 20.1" Widescreen LCD's 
KeyboardPowerCaseMouse
Logitech G15 Silverstone OP750 Lian-Li PC-A10B Logitech G5 
Mouse Pad
Harley Davidson 
  hide details  
Reply
post #4 of 7
Quote:
Originally Posted by Burn View Post
Technically speaking, there are a few differences:

1. NPT (in general) is a tapered thread, hence the T. It seals as the barb is screwed in and requires friction between the threads to seal properly. Generally, this is achieved by using teflon tape to ensure the threads slide properly between each other and seal.

2. G1/4 is a straight thread (no tapering). This type does NOT seal in the threads, which is why you ALWAYS see G1/4 barbs with an o-ring. The o-ring provides the seal between the barb and threading. This thread type is easier to use because it provides a much more consistent seal when compared to NPT. I'm not surprised it has become (essentially) a watercooling industry standard.
he hit it on the head plus you did anwser your own questions too


3/8 doesnt = 1/4
Black Beauty
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X6 Asus Crosshair IV XFX 5970BE Corsair Dominator 
Hard DriveOptical DriveOSMonitor
WD Raptor 150GBx2 Raid0 None Win 7 x64 Asus VW246Hx3 
KeyboardPowerCaseMouse
STD 101 Corsair AX1200 Corsair 800D Modified Logitech G310 
Mouse Pad
None 
  hide details  
Reply
Black Beauty
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X6 Asus Crosshair IV XFX 5970BE Corsair Dominator 
Hard DriveOptical DriveOSMonitor
WD Raptor 150GBx2 Raid0 None Win 7 x64 Asus VW246Hx3 
KeyboardPowerCaseMouse
STD 101 Corsair AX1200 Corsair 800D Modified Logitech G310 
Mouse Pad
None 
  hide details  
Reply
post #5 of 7
Thread Starter 
doh.....i mean, i kinda figured it wouldn't fit, i just wasn't sure if they were different standards but happen to actually fit or something like that. anyways, thanks guys...love this forum!
My *Virgin* HTPC
(13 items)
 
  
CPUMotherboardGraphicsRAM
Athlon X2 Brisbane 1.9GHz Foxconn A7GM-S 780G mATX Radeon HD 3200 2GB Kingston DDR2-800 (2x1gb) 
Hard DriveOptical DriveOSMonitor
300GB Sata I (soon to add more) Lite-On Blu-ray/DVD burner Vista Ultimate x64 24" Dell S2409Wb 
KeyboardPowerCaseMouse
Logitech G15 v2 Rosewill Stallion series 400-watt SilverStone SuGo mATX (black) Logitech G5 v2 
  hide details  
Reply
My *Virgin* HTPC
(13 items)
 
  
CPUMotherboardGraphicsRAM
Athlon X2 Brisbane 1.9GHz Foxconn A7GM-S 780G mATX Radeon HD 3200 2GB Kingston DDR2-800 (2x1gb) 
Hard DriveOptical DriveOSMonitor
300GB Sata I (soon to add more) Lite-On Blu-ray/DVD burner Vista Ultimate x64 24" Dell S2409Wb 
KeyboardPowerCaseMouse
Logitech G15 v2 Rosewill Stallion series 400-watt SilverStone SuGo mATX (black) Logitech G5 v2 
  hide details  
Reply
post #6 of 7
3/8 npt is much bigger.
G1/4 is mean't for rubber O-Rings, because the thread is even. The NPT thread is tapered, so really it's meant to be jammed in without an O-ring.

3/8npt 5/8 barbs have higher flow than even the bitspower 1/4" 1/2" barbs.
I picked up really nice nickel plated npt barbs for my swiftech radiator.
My System
(13 items)
 
  
CPUMotherboardGraphicsRAM
I7 920 Asus P6T 8800gt Sli Ocz XMP ddr3 1600 
Hard DriveOSMonitorPower
Seagate 320+250 Windows 7 nec 90gx2 Ocz 700W 
Case
Tagan Black Pearl 
  hide details  
Reply
My System
(13 items)
 
  
CPUMotherboardGraphicsRAM
I7 920 Asus P6T 8800gt Sli Ocz XMP ddr3 1600 
Hard DriveOSMonitorPower
Seagate 320+250 Windows 7 nec 90gx2 Ocz 700W 
Case
Tagan Black Pearl 
  hide details  
Reply
post #7 of 7
Just to toss in one extra tidbit... most of the time you can use o-ring sealed G3/8 (3/8" BSPP) fittings in parts tapped for 3/8" NPT provided that the threaded portion of the fitting is somewhat short. The older Swiftech radiators are a good example of a part which will accept G3/8 barbs without issue.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Water Cooling
Overclock.net › Forums › Cooling › Water Cooling › 3/8 NPT thread vs. G1/4" thread - Whats the difference??