How to pick the right tubing and fittings
One of the most confusing parts of building a custom loop is the fittings and tubing, by far. It can be quite stressful when you first look at all the options you have at PPCs when it comes to fittings and tubing. It is extremely important that you purchase compatible fittings and tubing for your custom loop, but it is much easier than you might think. I hope that this quick guide on how to pick out the correct fittings and tubing for your loop helps relieve some of the stress with your build.
First things first. Always ask yourself, “what tubing do I want to use for this loop?”, when you first start to plan your build. Start by deciding on either rigid tube; PETG, acrylic, copper, glass, etc, or soft tube; PVC, Neoprene, Polyurethane, etc. Both types of tubing have their uses and aesthetics. For a beginner watercooler, it is usually best to start with soft tubing, as it is easier to work with and is helpful when learning the basics. Rigid, or hard tubing, is often more difficult to work with, however it does provide different aesthetics as well as a more durable tubing. Whichever you choose decides what type of fitting you need. For soft tube, you’ll need either barb fittings like these, and clamps like these, or soft tube compression fittings like these. For rigid tubing you’ll need rigid tube fittings like these. Size is often a water cooler’s biggest concern, however the size of your tubing really doesn’t impact your loop’s performance at the end of the day. All tubing is measured with an O.D., or outer diameter, and an I.D., or inner diameter. For soft tubing you’ll want to pay close attention to both the O.D. and the I.D. when selecting your fittings. For rigid tubing you really only need to worry about the O.D. when it comes to fitting compatibility. With soft tubing, the tube’s dimensions are commonly listed in both standard and metric measurements. Don’t let this confuse you! Standard and metric values are not always interchangeable. For example: people will sometimes say 12mm = ½”, when a ½” is actually 12.7mm. Now this doesn’t make a particularly big difference with soft tubing, as you have much more room for error with soft tube. You do, however, always want to be sure to purchase tubing that matches the size of your fittings exactly, or vice versa. When it comes to rigid tubing, you only need to worry about the O.D., as the outside of the tubing is the only part that makes a seal with the fitting.
Various sizes of soft and hard tubing.
A lot was just covered about fittings, so be sure to keep the size of your fittings in mind when picking what you will use for your custom loop. Aside from the size, there are also a couple different types. Previously mentioned above were barbs/clamps for soft tubing, as well as two types of compression fittings. Barbs/clamps are the most basic type of fitting, as such, they are very easy to use as well. Just slide the clamp over your tubing, then slide the end of the tubing over the barb. Tighten down the clamp over the barb, and you’re all set! Compression fittings are somewhat similar for soft tubing, as they still have the barb. Instead of the clamp, they have a collar which threads onto the barb part of the fitting, over the tubing.
Soft tube over compression fitting barb
Soft tube installed on fitting with the collar.
The barb required for soft tubing, is why you need to be sure that the I.D. of your tubing matches your fittings. The clamp, or collar is why the O.D. of your tubing needs to match your fittings. Hard tube fittings are similar to soft tube compression fittings, however there isn’t a barb. Instead, the inner wall of the fitting has 1-3 o-rings for the O.D. of the tubing to press against to make a seal. This is why the I.D. of rigid tubing does not affect tubing compatibility. The rigid tube compression fitting works exactly like a soft tube compression fitting. You just tighten the collar and another o-ring onto the bottom of the fitting once your tubing is fully seated. All of this may be confusing at first, but once you start using watercooling fittings and tubing, you’ll quickly become used to how it all works together.
Hard tube installed in fitting with O ring.
Hard tube installed in fitting with O ring and collar.
Hard tube installed in various fittings.
Tools and Accessories
Now that you know what fittings and tubing you need for your build, you’ll need some tools to work with your gear. For soft tubing it’s pretty straight forward. All you really need is a tubing cutter, such as this one from Phobya. Those soft tubing cutters will also work with “soft” rigid tubing like PETG as well, but not for PMMA or acrylic. You can use a hacksaw and mitre kit like this one from Monsoon to cut practically any rigid tubing, aside from glass. For glass tubing, you’ll want to take a look at this cutting kit we put together here at PPCs. If you’re working with rigid tubing, and you’re planning on bending it, you’ll need to pick up a silicon bending cord like any of these here. Be sure to pick one up that matches the I.D. of your rigid tubing. You’ll also want a heatgun like this one, if you don’t have one at home already. It’s never a bad idea to grab some Tube Loob here, from Bleederhead Studios. Tube Loob is an extremely useful lubricant for your rigid tube bending, chamfering, cutting… or really anything you need to do with your tubing! When working with rigid tubing you will need to chamfer the ends of your tubing. Chamfering the ends helps take the sharp edge off of your freshly cut tubing. This will make it easier to install the tubing in your fittings, as well as save your O rings from damage during installation. You can find hand chamfering tools here, as well as PrimoChill’s RFB’s here. If you’d like to learn more about the RFB, take a look at our previous blog on it here. You’re probably thinking that this is a lot of tools, but wait, there’s more! A mandrel kit like any of these found here can be a useful set of tools to have for rigid tubing as well, but are by no means required. As you can see by now, working with soft tubing is far simpler, and requires far less tools. However, I would never discourage someone to get into rigid tubing, even as a first time watercooler. As long as you have the proper tools and motivation, you can make any kind of loop work for your build!
Tubing tools and accessories
Fittings, tubing, and all the tools you need for your custom loop build can be quite daunting, but I hope that this quick blog helped you sort out some of the topics that were confusing you. I would also encourage any newcomer to watercooling to check out resources like our Youtube channel here, as well as Reddit, Facebook, and other forums on the internet. There is no limit to what you can learn! Feel free to contact me directly at firstname.lastname@example.org if you have any questions or concerns about your next build!