Delrin 90 Degree elbows

About Delrin 90 degree elbows, has anyone here tried using them in their loop? Or does the philosophy "Elbows are bad. They are too constrictive!" apply with these? The Danger Dan ad claims that they are high-flow.

Your thoughts, please?

I have been known to use elbows. With a good pump, you really don't notice.

I think the philosphy of "elbows are bad", and similar other ones harken back to a time before most of us were using a good pump, when many were still using lower rated aquarium pumps, when every little tweak for flow mattered.

These days when everyone is running 120.2 or larger radiators, 10+ head pumps, and high flow blocks, it's not nearly as important.

My $0.02

If you want a high-flow 1/2" option go to the hardware store and get a 1/2" copper elbow. No added restriction for barbs and it's slightly curved, meaning a little less restriction than a sharp-angled 90 ...

That's a pretty expensive elbow...

I had set up a dual loop with 1st loop that had 2 90 deg elbows
The 2nd loop had no elbows.

Both loops had roughly the same amout of tube, both went though a tripple rads both went through 2 water blocks each.

The one with the elbow... the water trickled out and into the res (I have acrylic fish tank for a res I can visually see the amout of water that goes into the res both inlets are only 10 cm apart so its easy to compare).

The one without the elbow you can see a jet of water gushing out into the res.

I was suprised how much restriction there actually is I estimate that 2 elbows cut the flow by about half.

You can always get the long run copper elbows. Same as a regular copper ell but with a 3" radius ...

I appreciate the replies so far. The application this will be used in has the power supply directly above the vid card. As in this photo. There is only enough room for a 1/2 tube to pass between the card and the PSU, much less a normal bend. I think the copper short elbows will likely work the best, but will very likely test one against the delrin 'L' and describe what I observe here.

I have to refer to Martinm210 over at XS for this. Take a look at http://www.xtremesystems.org/forums/showthread.php?t=165383&highlight=elbows+restriction, and take a look at jayhall0315's thread at myth #5 on http://www.xtremesystems.org/forums/showthread.php?t=152686&highlight=elbows+restriction.

"1 90 copper tight elbow = 5.4" of 7/16" tubing"

The cheapest, least restrictive option is the simple 90 copper elbow. I personally remain the fan of the long sweep elbow (i.e. #5520K603 at mcmaster.com) as it is even less restrictive than the regular copper elbows. But of course it costs a lot more and regular elbows are readily available whereas the long sweep ones aren't.

I have a couple of spots where is just makes sense to use elbows, so I use the least restrictive ones I can, namely the long sweep ones. With a good pump, a few copper elbows aren't going to make a noticeable difference, but of course if it works to avoid them, then there is no reason to add restriction where it isn't necessary.

Nice links Voigts.

That test tells me one or two elbows will lower flow, but not kill it. It does add some restriction though. I do have to say if you are going to use an elbow, copper is the way to go.

Jas said:

Nice links Voigts.

That test tells me one or two elbows will lower flow, but not kill it. It does add some restriction though. I do have to say if you are going to use an elbow, copper is the way to go.

Click to expand...

Yes, I agree with all of this. Thanks for those links!

I was especially surprised to learn from the second link you posted that placing an elbow just before the pump will kill the flow. I would have never considered that when setting up the loop I needed these answers for. I didn't plan on using the elbow near the pump, but I am glad I learned that all the same.

The long copper elbows, while better for flow, probably wouldnt work in the given space?

Sweeping elbows are fine, sure they cause some pressure drop, but nothing to freak out about. The elbows to stay clear of are the hard 90 degree deals.