1 / PETG vs acrylic
Acrylic tubing is favoured for its higher melting point, meaning it’s less susceptible to higher coolant temperatures, but is trickier to heat and bend. Conversely, it’s much quicker to work with PETG, but it can deform if your coolant gets too warm and it occasionally suffers from kinks when bending.
2 / Work out lengths and bends
Pipe cleaners or thin metal rods are ideal for working out the lengths and locations of bends in your tubing. Place one end resting on the tube support inside your tube fitting, and bend the pipe cleaner to the required angle. You can now use it as a template.
3 / Use lubricant
The anti-kinking insert can become lodged inside the tube once it’s bent, so it’s important to use lubricant. Washing-up liquid works well for this purpose, but be sure to rinse the tube thoroughly afterwards.
4 / Install insert
The insert prevents the tube from kinking when you bend it, which will happen instantly without it. Place it so that there’s at least four inches on either side of your bend location.
5 / Heat tubing
Use a heavy-duty heat gun to warm the tubing evenly from 2in away, going back and forth quickly across either side of your bend point. PETG tubing takes least 15 seconds to become malleable, while acrylic takes longer. Too much heat will cause bubbles to form, so practise on a spare section first to find the right balance.
6 / Use tube bender
Once your tubing is heated correctly, feed it gently into your tube bender with the corner of the bend aligned with the centre of the section you just heated. If it doesn’t bend enough, try warming the tubing for a few more seconds.
7 / Allow tube to cool
With the tubing fed into the bending tool, if you’re happy with your work and the tube looks to be free of bubbles and deformities, allow it to cool for 30 seconds, by which time it will be strong enough to handle.
8 / Cut to size
To cut PETG or acrylic tubing, use a hacksaw with a fine-tooth blade, and gently allow the weight of the saw to cut through the tube at your desired location. Too much pressure can crack the tube, so take it easy.
9 / Use tube reamer
Finally, a tube reamer is required to chamfer the outer edge, so the tube slides into the fittings more easily. The reamer also has a tool for scraping the inside of the tube to remove any debris from cutting.