How far can I bend a PETG tube ?

[Call_Me_Daddy]

Hi everyone ! I am currently building my first custom loop using PETG tube, which involves a CPU, a GPU in a small case.

 

I'm facing the following problem. The Pump to cpu tube would require me to do a very quick 180°. I own a thermaltake bending kit which includes a 180° guide. However, in order to align my tube with the fittings, I'd have to do a shorter 180° bend than the tube allows. 

 

I'm not sure that I'm clear, please let me know if you need me to clarify. 

 

 

What are your thoughts ? How short can a PETG 180° bend be while being functional ? 

Do you have pictures of personal or seen experiences to help me figure out ? 

 

 

Thank you !

[For Science!]

5 hours ago, Insorior said:

 

I've done a few 180's for aesthetics. The 180 in the front left of my build still has some slack, so you can go even tighter, but not much. It also depends on your ID/OD how tight you can go. This is 16 mm tubing, so if you have 12 mm, you can go even tighter.

 

In my Ncase build, I have a 12 mm tube in a sharp 180 as well and this is pretty much the sharpest it can go I think. Hope it helps.

 

 

 

 

 

[Call_Me_Daddy]

8 hours ago, For Science! said:

I've done a few 180's for aesthetics. The 180 in the front left of my build still has some slack, so you can go even tighter, but not much. It also depends on your ID/OD how tight you can go. This is 16 mm tubing, so if you have 12 mm, you can go even tighter.

 

In my Ncase build, I have a 12 mm tube in a sharp 180 as well and this is pretty much the sharpest it can go I think. Hope it helps.

 

 

 

 

 

Thank you ! This feedback is actually useful.

Did you not have any flow problem with this last 180° ? It looks very sharp to me. Also what technique did you use to get it that clean ? 

 

 

I think my mystakes were both applying heat too close to the tube end (which honestly was unnecessary, I use 60cm tubes so it's more or less 1 use, I'm fine with "wasting" 1/10th of a 4€ tube if it can save me a motherboard or a 2080 ti), and cutting the tube where the bend already started which prevented it from being sealed.
 

 

I posted my plans in the end of my initial topic which you can check here : 

 

[Salticid]

The insertion depth of the base section of most compression fittings, from what I have read, is about 5mm. 

You want to have a straight line of at least a few mm past that, this way the tube is definitely in perfect 'O' shape and will seal properly in the fitting.

This guide does not include the mm's the cap takes - make sure to check and take this into account.  I found with a couple of my super short 90 degree turns I almost made it too short to have the cap on the tube and still seat the tube firmly and verify it was seated before sealing the cap.  LOL

 

I didn't buy the Thermaltake bending kit until after bending 3 of my lines.  I didn't do any 180s, but I have a lot of 90s.  I used the edge of my granite counter as a guide, and came up with some pretty clean, sharp 90s, and I really preferred the look of it to the Thermaltake 90 degree bend...  It's 16mm OD tubing and is probably as tight as you want to go with that OD.  That said, I am having zero flow issues, and no leaks at all 14+ hours into leak testing (knock on wood).

 

So, I think your 180s are fine. 

 

Edit to add:  I suppose a pic of what I mean would help.  LOL

 

[Call_Me_Daddy]

3 hours ago, Salticid said:

The insertion depth of the base section of most compression fittings, from what I have read, is about 5mm. 

You want to have a straight line of at least a few mm past that, this way the tube is definitely in perfect 'O' shape and will seal properly in the fitting.

This guide does not include the mm's the cap takes - make sure to check and take this into account.  I found with a couple of my super short 90 degree turns I almost made it too short to have the cap on the tube and still seat the tube firmly and verify it was seated before sealing the cap.  LOL

 

I didn't buy the Thermaltake bending kit until after bending 3 of my lines.  I didn't do any 180s, but I have a lot of 90s.  I used the edge of my granite counter as a guide, and came up with some pretty clean, sharp 90s, and I really preferred the look of it to the Thermaltake 90 degree bend...  It's 16mm OD tubing and is probably as tight as you want to go with that OD.  That said, I am having zero flow issues, and no leaks at all 14+ hours into leak testing (knock on wood).

 

So, I think your 180s are fine. 

 

Edit to add:  I suppose a pic of what I mean would help.  LOL

 

Thanks ! your tubing looks great  

 

My main problem with TT kit is that I can't manage to get clean angles, even if bending slowly. Even the 90° are rather 80 and they gave me results that I don't like. However it helps with having a guideline. 

 

I actually went with another idea (as seen on the other topic that I linked), using 90° fittings to go immediately on 180°s and only have to end up with a 90° to go down in the other fitting. It means that my tubes will not remain parallel nor perpendicular but I'm going to have way easier bends IMO. 

 

I'm getting my new tubes on wednesday and I just hope that everything's going to be fine

 

Thanks again !

[Call_Me_Daddy]

I just posted a build log video 

 

i wished my spoken English was a bit better ! 

I discuss all the events that occurred during building in order to help other people avoiding the traps.

 

the end result can be seen from 16mn, I hope you’ll like it !

 

thanks again for all the help !