90-degree rotary compression PETG fittings and general hard tube Q's

Dutt1113

[H]ard|Gawd
Joined
Jun 30, 2005
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I want to get into hard tubing PETG soon. I can't seem to find barely any hard tube compression fittings of this style. I think I've only seen bitspower and maybe koolane ones. Is it because they generally are not needed because you bend tubing yourself so straight fittings are all that's needed? What if you need a very tight 90-degree turn directly into or coming from a port? Do you just have to get creative with the bend so it's not such a tight 90 right direction in front of a port where a fitting would be?

Also what's the most common fitting size that will give me the most options for fittings and tubing? 1/2" or 12mm or 16mm? Also do you want to always match up tubing size to fitting and not try to convert imperial to metric or vice versa? Just get 1/2" tubing with 1/2" fitting or 12mm with 12mm, etc?
 
There are FITTINGS, and then there are ADAPTERS. Most commonly fittings have a male G1/4 (other sizes exist but are rarely used) thread at one end and compression(12mm, 16mm, 1/2", 5/8", etc.) at the other. Push fittings and barb fittings also exist but aren't nearly as common as they once were. ADAPTERS on the other hand have G1/4 threads at both ends (or at all 3 or 4 ends, in the case of T's, Y's, etc.). The G1/4 threads can be any combo of male or female (M/M, F/F, M/F, etc.).

As you've already found, most manufacturers now only make fittings, particularly hard-line fittings, in the simple straight style. In situations where a 90° fitting is required, you simply use a straight fitting in concert with a 90° ADAPTER (either rotary or "normal"). This does increase the cost nominally, but the trade-off is increased flexibility. One thing to keep in mind is that whereas FITTINGS come in either Hard or Soft tubing styles, ADAPTERS are tubing agnostic. So if you're moving from soft tubing to hard-line, you can reuse any adapters you already have and only need to buy the actual fittings.

Hope this helps.
 
Try and limit 90° bends as much as possible. They start adding up as to restricting your flow. While all the nice/tight PETG bends look nice, it's a huge trade-off, going for beauty at the expense of functionality. I tend more towards the functionality end of the spectrum, beauty be damned! :D
 
Colin Chapman: "never use a 90 degree bend when two 45 degree bends will fit"
 
I want to get into hard tubing PETG soon. I can't seem to find barely any hard tube compression fittings of this style. I think I've only seen bitspower and maybe koolane ones. Is it because they generally are not needed because you bend tubing yourself so straight fittings are all that's needed? What if you need a very tight 90-degree turn directly into or coming from a port? Do you just have to get creative with the bend so it's not such a tight 90 right direction in front of a port where a fitting would be?

Also what's the most common fitting size that will give me the most options for fittings and tubing? 1/2" or 12mm or 16mm? Also do you want to always match up tubing size to fitting and not try to convert imperial to metric or vice versa? Just get 1/2" tubing with 1/2" fitting or 12mm with 12mm, etc?

I went with 12mm tubing mostly for aesthetics. Performance of the loop has been excellent and it was easy to work with. As for the fitting/adapter, Bitspower seems to be about the best bet in regard to the amount of options available. I'll be using one for the upper radiator so I can move the horizontal tube above the motherboard. As for using a pair of 45s over a 90°, flow restriction can actually be worse with the two fittings over the single 90°.

 
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