- Joined
- Feb 7, 2005
- Location
- Kenosha, WI.
EDITS UNDERWAY AS OF 12/13/07.
The purpose of this guide is to outline some basic characteristics of commonly used tubing for PC watercooling, and some pros and cons related to each type of tubing. This is not intended to be a defacto guide to all types of tubing, or a breakdown of the actual specifications for each tubing (although links to spec sheets are provided where available), but as a general means help you choose tubing that may be best suited to your needs.
Information contained is from personal experience, other forum member's experiences, and actual specifications of tubing.
Tubing Measurement
Tubing is measured in an ID (inner diameter) and an OD (outer diamter). The two most common ID's used in the US are 1/2" and 3/8". In Europe and elsewhere, a 1/4" ID is common.
There is also a growing number of people starting to use 7/16" ID tubing. The big differences between the usual 1/2" and 3/8" are flow rate, pressure drop, and bend radius. The 7/16" tubing seeks to achieve a happy medium between the two. It used with 1/2" fittings, and is stretched over the fittings. It is supposed to provide a lower pressure drop in smaller loops, while achieving good flow, and a better bend radius.
The OD of your tubing is very important. The thicker the OD the more resistant to kinking the tubing will be. For 1/2", and 3/8" ID tubing the desired thickness is a 1/8" wall. For 7/16" tubing a 3/32" wall is recomended.
1/2" Id tubing should have an OD of 3/4"
7/16" ID tubing should have an OD of 5/8"
3/8" ID tubing should have an OD of 5/8"
Types of commonly used tubing
A Quick Note on staining/buildup.
While High grade tubing such as Tygon, or Clearflex60 tends to resist staining and buildup, a coolant mixture that features additives that can produce substrates (such as Highlighter ink, or some algaecides) may eventually collect and stain the tubing. Particulates that result from corrosion will in particular cloud the tubing. Keeping your tubes clean and clear is as much about your coolant mixtures and loop maintenance as it is about the type of tubing you use.
3/8 - 1/2 INCH ID tubing
Tygon R-3606.
Bends easily, and greatly resists kinking. Non reactive, non corrosive, tends to resist staining, resists buildup on the inner walls. Costly, 2 to 3 times more expensive than other tubing.
Staining can and does occur with use of Glycol based addatives (antifreeze and similar products). staingin happens over time and produces a "cloudy" look.
Spec sheet
Pros:
1/8” walled tubing very resistant to kinking
Clear
Non reactive
Less permeable than rubber based tubing
Crack resistant
Bends Easily
Cons:
PRICE
Stains over time
Tygon R-3400.
Tygon R-3400 is a black UV, chemical and weathering resistant tubing. Stiffer than the R-3603 tubing, but provides more chemical resistance. Slightly more expensive than R-3603. Not A very common Tubing, but has recently shown some interest among forum members.
Pros:
1/8” walled tubing extremely resistant to kinking
Non reactive
Less permeable than rubber based tubing
Exremely Crack resistant
Tends to resist staining
Inhibits algea growth.
Cons:
PRICE
Unable to see through or into tubing.
Clearflex 60
A popular alternative to Tygon. Crystal clear, non-oxidizing, resistant to buildup. Bends easily, resists kinking.
Spec sheet
Check spec sheet for chemical reactions.
Pros:
1/8” walled tubing very resistant kinking.
Crystal clear.
Non reactive to many common chemicals.
Price.
Bends Very well.
Cons:
May react with some chemicals.
Can stain.
MasterKleer
Extremely clear, albiet stiffer tubing, but still bends well, resistant to kinking except in tight bends. Resistant to buildup. (Very popular 7/16" tubing)
Spec sheet at McMaster
Pros:
Price
Extremely clear (good looking)
Non reactive to most chemicals
Decently resistant to kinking.
Cons:
A bit stiff.
May react with some chemicals.
Can stain.
PrimoFlex
A popular silicone based tubing that is UV reactive. Resists kinking well, and bends easily. It is porous, so coolant loss due to evaporation through the tubing will happen over time. Availabel in many colors, most of which are UV reactive.
NOTE: The UV glow of the tubing tends to be less than that of the glow produced by coolant additives. UV additives may actually reduce the over all “glow”
Unable to locate a Spec Sheet.
Pros:
1/8” walled tubing is extremely resistant to kinking
Very pliable and easily routed.
Price
Color choices
Cons:
Not as clear as other tubing.
Not very resistant to build up on inner walls.
May react with certain chemicals.
Somewhat porous, coolant vapor will leak through over time.
Vinyl
A common tubing that can be found at many hardware stores. It is very stiff, but resists crimping very well, although very easy to kink if bent sharply. Readily available, easy to find, and inexpensive. Usually you can find it in two varieties. A somewhat clear variety, that is fairly stiff, and a reinforced variety that is grey with a white crisscross belting. The reinforced form is extremely stiff, and does not bend particularly well, but is extremely difficult to kink. Worm drive hose clamps are essential with vinyl tubing.
There are many manufactures of Vinyl tubing.
This Spec sheet is just an example of one.
Pros:
Very cheap
Very easy to find.
The clear variety is relatively clear.
Cons:
Very stiff (especially the reinforced variety)
May harden and possibly crack over time.
May react with certain chemicals.
Not very resistant to buildup.
Kinks pretty easily
1/4 INCH ID tubing
I am currently researching for more commonly used 1/4" ID tubing.
Tygon R-3606.
See above.
Createc PUR
A polyether compound tubing manufactured in Germany. A common type tubing for European 1/4" ID systems. The clear variety is fairly clear. It is also available in UV reactive colors.
There is also a Polyester compound variant, it has a yellow tint to it.
PROS:
Small diameter tubing it easier to route, and resists kinking.
Durable
Variety of colors available
Checmical resistant
CONS:
May react to some chemicals
Availability outside Europe.
Vinyl
See above.
NOTE: 1/4" Vinyl PVC tubing kinks VERY easily.
Hose Clamps.
Do you need clamps? Some setups may not need hose clamps to keep conenctiosn from leaking under normal operating conditions. These are usually systems using undersized tubing (Such as a 7/16" ID tubing running on 1/2" ID Barbs), or on overly large, multipel pronged barbs.
However, Using hose clamps is HIGHLY recommended. There are a variety of clamps that can be used, the most common type is the Worm Drive Clamp. These are metal clamps that feature a screw along the outside, which is turned to tighten or loosen the clamp. The upside of this type of clamp is it is extremely durable, and can be tightened down to ensure a completely leak free connection, no matter how much pulling or tugging you do. Complaints about these types of clamps are usually due to their lack of aesthetics, and the diffculty in tightening them in hard to reach spots.
Another common type of clamp are either plastic or metal "Snap" clamps. These are tightened by pinching the tops together so that the two sides "lock". These are generally not as durable (especially the plastic ones) as worm drive clamps, and do not provide the same level of leak protection a worm drive clamp can, they are however easier on the eyes, and generally thought to be easier to work with.
Pinch clamps can also be used, but I haven't seen many instances where people have used them. These are metal clamps (usually) that act like a spring. Pinching the top results in the clamps opening up so it can be moved into position, then the clamp is allowed to rest freely on the tube as its will naturally impart pressure on the tubing. These generally do not seal nearly as well as "Snap" clamps, or worm drive clamps, but are extremely easy to work with.
The "Ghetto" hose clamp. More often than not the "Ghetto" alternative to hose clamps is the Zip tie. They can provide great leak protection if tightened far enough, are easy on the eyes, and most importantly cheap. However removal can be issue, generally requiring the tubing be cut as well as the zip tie.
Bending those tubes.
The whole reason we use flexible tubing is so we can bend the tubbing into curves to fit everything together. Ideally we want the shortest distance possible between components, along with the most flow possible. Tubing that bends easier, yet remains resistant to to kinking will provide the cleanest bends, and won't collapse on itself as it bends.
The tighter your bends are going to be, the more flexible you will want you tubing (but still maintain the ability to not kink or collapse). Keep in mind, overly radical bends on too stiff of tubing may partially collapse the tubing and reduce flow.
Working with Tight bends, or stretching the tubing over oversized barbs/pipes
Sometimes, no matter how soft and flexible the tubing is, it just wont fit over the barbs, or bend as sharp as you would like. The solution to this is generally to heat the tubing up. This can generally be accomplished by soaking the tubing in VERY hot water, or using a heat source such as a blow dryer.
Soaking the tubing is the method with the least amount of potential to harm the tubing. Although it may harm you when you handle it. Wearing gloves of some kind, or even an oven mitt may be desirable when working with tubing in this manner especially if boiling water is used.
If the entire length of tubing is soaked it should become much more pliable (material dependant) and will be easier to bend and or stretch. Once the tubing cools down it will hold its new shape. Soaking an entire piece is a great way to force really tight bends.
Soaking the ends in boiling water can greatly aid in slipping the tubing over the ends of oversized barbs, or pipes on a heater core or radiator.
The hairdryer/heat source method is good for localized work, although the potential to burn the tubing exists. If you are using this method be careful to keep the heat source far enough away as to not over heat the tubing, and do not apply the heat for too long, or else the tubing may become damaged.
--------------------------------------------
Thanks to Sneaky for providing most of the following:
Durometer Ratings of popular Tubing: (lower durometer = softer/more flexible)
Tygon Ultra-Soft R-1000 Durometer: 40A
Primoflex/Silicone Durometer: 50A
Tygon Chemical R-3603 Durometer: 55A
Chemical PVC/Clearflex60 Durometer: 60A
Tygon R-3400 Durometer 64A
General PVC/Masterkleer Durometer: 67A
Vinyl Durometer: 70A
Braid-Reinforced Vinyl Durometer: 73A
--------------------------------------------
An over view of common synthetic tubing at McMaster
The purpose of this guide is to outline some basic characteristics of commonly used tubing for PC watercooling, and some pros and cons related to each type of tubing. This is not intended to be a defacto guide to all types of tubing, or a breakdown of the actual specifications for each tubing (although links to spec sheets are provided where available), but as a general means help you choose tubing that may be best suited to your needs.
Information contained is from personal experience, other forum member's experiences, and actual specifications of tubing.
Tubing Measurement
Tubing is measured in an ID (inner diameter) and an OD (outer diamter). The two most common ID's used in the US are 1/2" and 3/8". In Europe and elsewhere, a 1/4" ID is common.
There is also a growing number of people starting to use 7/16" ID tubing. The big differences between the usual 1/2" and 3/8" are flow rate, pressure drop, and bend radius. The 7/16" tubing seeks to achieve a happy medium between the two. It used with 1/2" fittings, and is stretched over the fittings. It is supposed to provide a lower pressure drop in smaller loops, while achieving good flow, and a better bend radius.
The OD of your tubing is very important. The thicker the OD the more resistant to kinking the tubing will be. For 1/2", and 3/8" ID tubing the desired thickness is a 1/8" wall. For 7/16" tubing a 3/32" wall is recomended.
1/2" Id tubing should have an OD of 3/4"
7/16" ID tubing should have an OD of 5/8"
3/8" ID tubing should have an OD of 5/8"
Types of commonly used tubing
A Quick Note on staining/buildup.
While High grade tubing such as Tygon, or Clearflex60 tends to resist staining and buildup, a coolant mixture that features additives that can produce substrates (such as Highlighter ink, or some algaecides) may eventually collect and stain the tubing. Particulates that result from corrosion will in particular cloud the tubing. Keeping your tubes clean and clear is as much about your coolant mixtures and loop maintenance as it is about the type of tubing you use.
3/8 - 1/2 INCH ID tubing
Tygon R-3606.
Bends easily, and greatly resists kinking. Non reactive, non corrosive, tends to resist staining, resists buildup on the inner walls. Costly, 2 to 3 times more expensive than other tubing.
Staining can and does occur with use of Glycol based addatives (antifreeze and similar products). staingin happens over time and produces a "cloudy" look.
Spec sheet
Pros:
1/8” walled tubing very resistant to kinking
Clear
Non reactive
Less permeable than rubber based tubing
Crack resistant
Bends Easily
Cons:
PRICE
Stains over time
Tygon R-3400.
Tygon R-3400 is a black UV, chemical and weathering resistant tubing. Stiffer than the R-3603 tubing, but provides more chemical resistance. Slightly more expensive than R-3603. Not A very common Tubing, but has recently shown some interest among forum members.
Pros:
1/8” walled tubing extremely resistant to kinking
Non reactive
Less permeable than rubber based tubing
Exremely Crack resistant
Tends to resist staining
Inhibits algea growth.
Cons:
PRICE
Unable to see through or into tubing.
Clearflex 60
A popular alternative to Tygon. Crystal clear, non-oxidizing, resistant to buildup. Bends easily, resists kinking.
Spec sheet
Check spec sheet for chemical reactions.
Pros:
1/8” walled tubing very resistant kinking.
Crystal clear.
Non reactive to many common chemicals.
Price.
Bends Very well.
Cons:
May react with some chemicals.
Can stain.
MasterKleer
Extremely clear, albiet stiffer tubing, but still bends well, resistant to kinking except in tight bends. Resistant to buildup. (Very popular 7/16" tubing)
Spec sheet at McMaster
Pros:
Price
Extremely clear (good looking)
Non reactive to most chemicals
Decently resistant to kinking.
Cons:
A bit stiff.
May react with some chemicals.
Can stain.
PrimoFlex
A popular silicone based tubing that is UV reactive. Resists kinking well, and bends easily. It is porous, so coolant loss due to evaporation through the tubing will happen over time. Availabel in many colors, most of which are UV reactive.
NOTE: The UV glow of the tubing tends to be less than that of the glow produced by coolant additives. UV additives may actually reduce the over all “glow”
Unable to locate a Spec Sheet.
Pros:
1/8” walled tubing is extremely resistant to kinking
Very pliable and easily routed.
Price
Color choices
Cons:
Not as clear as other tubing.
Not very resistant to build up on inner walls.
May react with certain chemicals.
Somewhat porous, coolant vapor will leak through over time.
Vinyl
A common tubing that can be found at many hardware stores. It is very stiff, but resists crimping very well, although very easy to kink if bent sharply. Readily available, easy to find, and inexpensive. Usually you can find it in two varieties. A somewhat clear variety, that is fairly stiff, and a reinforced variety that is grey with a white crisscross belting. The reinforced form is extremely stiff, and does not bend particularly well, but is extremely difficult to kink. Worm drive hose clamps are essential with vinyl tubing.
There are many manufactures of Vinyl tubing.
This Spec sheet is just an example of one.
Pros:
Very cheap
Very easy to find.
The clear variety is relatively clear.
Cons:
Very stiff (especially the reinforced variety)
May harden and possibly crack over time.
May react with certain chemicals.
Not very resistant to buildup.
Kinks pretty easily
1/4 INCH ID tubing
I am currently researching for more commonly used 1/4" ID tubing.
Tygon R-3606.
See above.
Createc PUR
A polyether compound tubing manufactured in Germany. A common type tubing for European 1/4" ID systems. The clear variety is fairly clear. It is also available in UV reactive colors.
There is also a Polyester compound variant, it has a yellow tint to it.
PROS:
Small diameter tubing it easier to route, and resists kinking.
Durable
Variety of colors available
Checmical resistant
CONS:
May react to some chemicals
Availability outside Europe.
Vinyl
See above.
NOTE: 1/4" Vinyl PVC tubing kinks VERY easily.
Hose Clamps.
Do you need clamps? Some setups may not need hose clamps to keep conenctiosn from leaking under normal operating conditions. These are usually systems using undersized tubing (Such as a 7/16" ID tubing running on 1/2" ID Barbs), or on overly large, multipel pronged barbs.
However, Using hose clamps is HIGHLY recommended. There are a variety of clamps that can be used, the most common type is the Worm Drive Clamp. These are metal clamps that feature a screw along the outside, which is turned to tighten or loosen the clamp. The upside of this type of clamp is it is extremely durable, and can be tightened down to ensure a completely leak free connection, no matter how much pulling or tugging you do. Complaints about these types of clamps are usually due to their lack of aesthetics, and the diffculty in tightening them in hard to reach spots.
Another common type of clamp are either plastic or metal "Snap" clamps. These are tightened by pinching the tops together so that the two sides "lock". These are generally not as durable (especially the plastic ones) as worm drive clamps, and do not provide the same level of leak protection a worm drive clamp can, they are however easier on the eyes, and generally thought to be easier to work with.
Pinch clamps can also be used, but I haven't seen many instances where people have used them. These are metal clamps (usually) that act like a spring. Pinching the top results in the clamps opening up so it can be moved into position, then the clamp is allowed to rest freely on the tube as its will naturally impart pressure on the tubing. These generally do not seal nearly as well as "Snap" clamps, or worm drive clamps, but are extremely easy to work with.
The "Ghetto" hose clamp. More often than not the "Ghetto" alternative to hose clamps is the Zip tie. They can provide great leak protection if tightened far enough, are easy on the eyes, and most importantly cheap. However removal can be issue, generally requiring the tubing be cut as well as the zip tie.
Bending those tubes.
The whole reason we use flexible tubing is so we can bend the tubbing into curves to fit everything together. Ideally we want the shortest distance possible between components, along with the most flow possible. Tubing that bends easier, yet remains resistant to to kinking will provide the cleanest bends, and won't collapse on itself as it bends.
The tighter your bends are going to be, the more flexible you will want you tubing (but still maintain the ability to not kink or collapse). Keep in mind, overly radical bends on too stiff of tubing may partially collapse the tubing and reduce flow.
Working with Tight bends, or stretching the tubing over oversized barbs/pipes
Sometimes, no matter how soft and flexible the tubing is, it just wont fit over the barbs, or bend as sharp as you would like. The solution to this is generally to heat the tubing up. This can generally be accomplished by soaking the tubing in VERY hot water, or using a heat source such as a blow dryer.
Soaking the tubing is the method with the least amount of potential to harm the tubing. Although it may harm you when you handle it. Wearing gloves of some kind, or even an oven mitt may be desirable when working with tubing in this manner especially if boiling water is used.
If the entire length of tubing is soaked it should become much more pliable (material dependant) and will be easier to bend and or stretch. Once the tubing cools down it will hold its new shape. Soaking an entire piece is a great way to force really tight bends.
Soaking the ends in boiling water can greatly aid in slipping the tubing over the ends of oversized barbs, or pipes on a heater core or radiator.
The hairdryer/heat source method is good for localized work, although the potential to burn the tubing exists. If you are using this method be careful to keep the heat source far enough away as to not over heat the tubing, and do not apply the heat for too long, or else the tubing may become damaged.
--------------------------------------------
Thanks to Sneaky for providing most of the following:
Durometer Ratings of popular Tubing: (lower durometer = softer/more flexible)
Tygon Ultra-Soft R-1000 Durometer: 40A
Primoflex/Silicone Durometer: 50A
Tygon Chemical R-3603 Durometer: 55A
Chemical PVC/Clearflex60 Durometer: 60A
Tygon R-3400 Durometer 64A
General PVC/Masterkleer Durometer: 67A
Vinyl Durometer: 70A
Braid-Reinforced Vinyl Durometer: 73A
--------------------------------------------
An over view of common synthetic tubing at McMaster
Last edited:
