Braided stainless tubing throughout - Page 2

#11: Post by **lancealot** » June 10th, 2021, 6:10 pm

The breville dual boiler uses ptfe hoses throughout. Water path and steam path. The hose itself is not a typical failure point. (I have never heard of a hose failing on one)

The o ring that seals the ferrule where the hose meets the boiler(s) is prone to leaking due to o ring failure. It is an odd design though.

#12: Post by **PeetsFan** » June 10th, 2021, 7:21 pm

JRising wrote:You can use PTFE tubing throughout for the pressurized parts and silicon for all the atmospheric pressure hoses. It's one way to keep a machine affordable as well as quieter than copper tubing throughout.

When I (Rudely) corrected PeetsFan earlier I had intended to write more so that it wasn't going to appear so rude, Sorry PeetsFan, and include a photo of a stainless braided hose I have somewhere that is severed and shows that it's a nylon braided rubber hose on the inside of that stainless mesh braid coating. But I can't find the hose anywhere, so I just sent the Wikipedia copy/paste and let it go.

Flexible hoses are only needed in places where you connect a vibrating (pump) component to the stationary (fittings) components to absorb the vibrations nice and quietly. It's classy to use a braided stainless hose like a Rancilio Silvia, but much more expensive Rocket Giottos and things just use a teflon hose bent in a big u-turn to absorb the vibration. I've seen both blow, but the teflon blows far more often, right at the middle of the u-turn, outer edge, usually when the expansion valve is calcified shut.

No worries; I didn't feel the slightest bit offended by your correction.

Here's a photo of the inside of my Breville Infuser, when I'd replaced its pump. As you can see, all of the tubing is either Teflon or some other kind of plastic for the no-pressure tubes for drain and fill.

I'm not a materials expert, but surely there is a reason why the prosumer and professional machines use copper pipe instead of these tubes. My assumption is durability and reliability, but maybe you or someone else understands this better.

#13: Post by **Bluenoser** » June 10th, 2021, 7:47 pm

PeetsFan wrote: I'm not a materials expert, but surely there is a reason why the prosumer and professional machines use copper pipe instead of these tubes. My assumption is durability and reliability, but maybe you or someone else understands this better.

John from Decent explained the rationale for using non-copper tubing in their Decent Espresso machine. It is somewhere here on HB I think.. I got the impression that the newer designs used inside Nespresso and other such machines are non-metal for piping and more reliable. Thermal expansion was one reason for using non-metal piping. Another problem with copper is corrosion from chemicals inside common water sources. Corrosion and scale play hell with metal boilers, tubing and plated brass mushrooms.. (as I've discovered in my machine)

#14: Post by **yakster** » June 10th, 2021, 7:52 pm

Teflon is used in RO systems instead of copper because of the corrosive nature of reverse osmosis water.

#15: Post by **pizzaman383** » June 10th, 2021, 8:02 pm

harrisonpatm wrote:Good to know, everybody. Thank you all.

I had this idea in my head: one of the (many) complexities to designing and building an espresso machine is fitting, shaping, bending all the pipes just so. It'd be neat if you just had entirely flexible options that you could swap out or pick out of a box of lengths. That's just be my, ahem, pipe dream for now.

I used braided steel lines when I was prototyping my DIY lever designs then replaced them with copper once I had the design settled.

#16: Post by **PeetsFan** » June 12th, 2021, 12:16 pm

Bluenoser wrote:John from Decent explained the rationale for using non-copper tubing in their Decent Espresso machine. It is somewhere here on HB I think.. I got the impression that the newer designs used inside Nespresso and other such machines are non-metal for piping and more reliable. Thermal expansion was one reason for using non-metal piping. Another problem with copper is corrosion from chemicals inside common water sources. Corrosion and scale play hell with metal boilers, tubing and plated brass mushrooms.. (as I've discovered in my machine)

Two things are certain:
Copper tubing costs more, especially in labor.
Copper tubing is less forgiving of rough shipping & handling

In home plumbing, copper is steadily losing out to PEX plumbing.

BUT - Will the Italians replace copper with Teflon? I just don't think so. They're very steeped in tradition.

#17: Post by **Bluenoser** » June 12th, 2021, 7:15 pm

PeetsFan wrote:
BUT - Will the Italians replace copper with Teflon? I just don't think so. They're very steeped in tradition.

You can't even get them to put a bottomless PF in their machines. (Lelit being the exception)

June 12th, 2021, 7:25 pm

Bezzera being the exception, too. Mine came with double-spouted and bottomless PF's and the solid wood handles and thick chrome plating are fantastic. I only use the bottomless PF. The dual-spout has the back flush insert and I use it for back flush cleaning only.

June 12th, 2021, 9:22 pm

Not just the Italians. But conversations like these make me think of the nature of innovations: someone's gotta try the dumb idea to see what works and what doesn't so that things can improve. If beans + hot water + pressure = espresso, the options are many. Now I'm just waiting to see somebody put together a machine using just PEX, just to see if it works

#20: Post by **Jeff** » June 12th, 2021, 9:50 pm

PEX is only stable to 120 C. Steam temperatures generally exceed that.