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Everyday uses for PVC water pipe

tomtilley.net

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Re: Everyday uses for PVC water pipe

#101
post #84

Earlier quoted context omitted.

If you have a water dispenser (through a refrigerator), do you fill and dump two glasses before getting yourself a glass of water to consume?

I hadn't got a water dispenser like that but I'd be really surprised to find that the internal reservoir and piping was made of anything except for plastic.

Some actually have coiled copper (it transmits "cold" better) - but almost all of them have a filter.

Re: Everyday uses for PVC water pipe

#102

Earlier quoted context omitted.

If you have a suggestion I'm sure it would be welcome. Generally, if there were a better solution we would be using it. If you know of one, you should share it with us. If you don't, maybe work on finding one.

GP made multiple suggestions and personally I read their comment as “here are some ideas, does anyone else have any?” Not an indictment of people using this material or a statement that there must be something better and everyone must switch to it. Your comment comes across a bit off-tenor. Also keen to hear if folks on here have other ideas (before you ask: I don’t have any). > Generally, if there were a better solu…

I agree, improvement is important.

There is a saying, "everyone is a mechanical engineer". As one, we consistently have to field this kind of question in design reviews, etc.

The question, in general, is why don't you invent a new material to solve that problem, the answer generally is we don't have the budget on this $100k project to ask DOW chemical or 3M or BASF to spend 10 years designing a new plastic for us.

So while I agree in concept, in practice it's not really a helpful question/suggestion.

The way we MEs have learned to answer this question is to say we made from the most appropriate material given the requirements and operating conditions, if anyone is aware of a material that we should also try then please speak up.

Almost never is there someone that speaks up.

The other thing is there is a huge difference between "material exists " and material is mass produced and available to the general public.

In this case, to compete with PVC pipe by making some new better resin, extruding it into pipe, then making it readily available on the general market so that it's available enough to write a guidebook on how to use it to make stuff. That's a billion dollar investment.

Re: Everyday uses for PVC water pipe

#103
post #38

Folks on YouTube cut, heat, and flatten PVC and then scratch build scale models out of it. This working excavator is rather extraordinary. https://m.youtube.com/watch?v=qam0DmWq_No&pp=ygUTcHZjIHBpcGU...

This deserves its own HN post.

Agreed, submitted https://news.ycombinator.com/item?id=37534779

Re: Everyday uses for PVC water pipe

#104
post #73
post #9

Interestingly, plumbing your house with PVC water pipe is not a fantastic idea and is not allowed under most plumbing codes. The specific issue is that PVC loses strength at higher temperatures, so performance at household water pressures with household hot water is somewhat marginal. Manufacturers don’t rate their pipe at all above 140 degrees F. Having your pipe burst when you run hot water through it is undesirabl…

In the country I live virtually every house is plumbed with PVC. Works great and only fails if done extremely poorly. Of course, they don't run hot water through it. Most people here think it is bizarre to have a big tank of hot water at one end of the house (often the garage) that is sent throughout the house, rather than having instant hot water heaters at the point of use.

The efficiency of hot water heaters is actually surprisingly good. A modern insulated tank retains heat very well. And it's more flexible for heating options since the water can be heated slowly over time. You can now get heat pump water heaters that are more efficient than tankless heaters. [0]

Water heaters are pretty clever, in a low-tech sort of way. Technology Connections did a good video about them recently. [1]

0: https://livefreehc.com/blog/heat-pump-water-heater-vs-tankle...

1: https://www.youtube.com/watch?v=Bm7L-2J52GU

Re: Everyday uses for PVC water pipe

#105
post #25

Earlier quoted context omitted.

It's certainly not 'way worse'. CPVC/PVC has its advantages and disadvantages, just like every other piping method. CPVC can become less pliable over time, particularly for hot water, but properly (by code) supported/strapped and glued, it can last for decades. It, like PEX, should be run to a well-secured, copper stub out where it sticks out of the wall in an area where it could be damaged. Copper is not without its…

If you go PEX, I highly recommend going the entire Uponor route and use the expansion tooling (get the powered one). No need to worry about incorrect crimps and it just works.

If only Uponor would flesh out their fitting portfolio for 3/8”. 3/8” PEX is a near-perfect material for hot water distribution to sinks and showers — jurisdictions seem to have settled on the 0-2gpm range for sinks and showers, and 3/8” PEX high velocity at moderate pressure loss at these flows, which is exactly what you want. [0] But Uponor has very limited 3/8” parts, and using their brass fittings in that small size makes me a bit uneasy due to potential erosion issues. Give me stainless steel or plastic, please, or at least something where the very narrow part that inserts into the 3/8” PEX tube is highly resistant to fast-moving hot water.

If you consider push-to-connect fittings acceptable, something like this could be very nice for connecting tubing to shower valves:

https://www.johnguest.com/us/en/cts-fittings/prolock/threade...

(3/8” is permitted by code, but not by the tables in the UPC - actual math is required.)

[0] PEX, unlike copper, tolerates fairly high velocity hot water. Copper has a delicate passive layer on the inside, and scrubbing it off will erode the pipe. The interior of a PEX pipe, is, drumroll please, just PEX, which is a rather tough polymer that is not going to be easily eroded away.

Re: Everyday uses for PVC water pipe

#106
post #53

Folks on YouTube cut, heat, and flatten PVC and then scratch build scale models out of it. This working excavator is rather extraordinary. https://m.youtube.com/watch?v=qam0DmWq_No&pp=ygUTcHZjIHBpcGU...

It even has windshield wipers, that's pretty wild: https://youtube.com/watch?v=qam0DmWq_No&t=48m1s

He hand drilled each and every hole for the perforated step plates. Just in awe of both the skill and the patience.

He also seems to be working with several tools he made himself.

Re: Everyday uses for PVC water pipe

#107
post #98

Folks on YouTube cut, heat, and flatten PVC and then scratch build scale models out of it. This working excavator is rather extraordinary. https://m.youtube.com/watch?v=qam0DmWq_No&pp=ygUTcHZjIHBpcGU...

PVC is quite toxic in a variety of ways. I would never heat, cut PVC voluntarily, especially without full breathing protection

I was wondering about that myself... It also gave me the willies when he was using the table saw cutting those tiny little strips with his fingers so close to the blade!

Re: Everyday uses for PVC water pipe

#108
post #98

Folks on YouTube cut, heat, and flatten PVC and then scratch build scale models out of it. This working excavator is rather extraordinary. https://m.youtube.com/watch?v=qam0DmWq_No&pp=ygUTcHZjIHBpcGU...

PVC is quite toxic in a variety of ways. I would never heat, cut PVC voluntarily, especially without full breathing protection

We never see his face so I'm not sure where your assumptions are coming from, but I'm sure someone with enough PVC experience to make a working model excavator out of PVC is probably taking the necessary safety precautions..
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