We have some very nice ceramic-washer taps. But they come with inserts
that produce back-pressure and restrict flow, with the aim of shaping
the water into a steady stream. Taking them out gives a very ragged
flow. To the 3D printer!
This is the standard insert. (One from the bath tap, one from the
kitchen tap; not quite the same measurements.)
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One vernier caliper and OpenSCAD later, I have a design for an outer
shell which ought to fit into the tap.
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Then it's a matter of making up some hydrodynamics, or more to the
point thinking of something that might work and seeing if it helps.
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One print later...
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Yup, it works rather better than before, while not seriously
cutting the flow.
With no insert: a ragged stream and a relatively small cleared area on
the bottom of the sink, indicating a low flow rate.
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With insert: a clearer stream and a rather larger cleared area (the
cold tap is full on in both cases).
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Nozzle design is evidently a Black Art, but this seems like a good start.
- Posted by Michael Cule at
11:59am on
20 April 2018
You have just threatened the livelihood of an entire micro-profession of tap nozzle designers and manufacturers.
They will be after you...
- Posted by RogerBW at
12:05pm on
20 April 2018
You can buy them on Amazon (the sizes of the two weren't exactly the same, but probably close enough) – but those are the flashy aerator type, rather than simply maximising water flow which was what we were after.
- Posted by Owen Smith at
06:53pm on
20 April 2018
What was wrong with the original ones in the taps? You don't say.
If that is full flow you must have low water pressure. Before I fitted my water softener it used to be if I turned on the kitchen cold tap full I would get drenched with the splash back and have to change my shirt. Mains pressure was well above (by a factor of more than 3 I believe) what the water softener was specificied for, so I fitted a 22mm pressure reducing valve in the incoming pipe. Flow is still great, and I don't get splashed any more.
I originally fitted a 15mm pressure reducing valve. This reduced flow quite a lot, so I changed it for the 22mm one. This may be the root of your problem if a pressure reducing valve was fitted for your softener.
- Posted by Chris Bell at
10:59am on
21 April 2018
What he wrote was that the taps "come with inserts that produce back-pressure and restrict flow, with the aim of shaping the water into a steady stream".
You say "if I turned on the kitchen cold tap full I would get drenched with the splash back and have to change my shirt" -- your problem was clearly quite different, indeed opposite.
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