Building a lever machine.... from scratch - Page 15

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Jayhov
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Joined: 11 years ago

#141: Post by Jayhov »

You are truly nuts... and I love it!

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bidoowee (original poster)
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Joined: 8 years ago

#142: Post by bidoowee (original poster) »

Thanks for the kind words and encouragement - it all helps!

Plumbing, part two.

There were a couple of missteps in the last round of plumbing that I had/wanted to fix. The first had to do with the way that the parts were supported when they were brazed. The intense heat from the oxy-acetylene torch combined with the pressure of the vise caused the brass parts to soften and deform. The result was a complete set of oval compression fittings - :cry:

I made a couple of compression dies from some scrap aluminum to try to salvage the work.



Fairly straight forward to use: drop them into the vise and crush the living *&^#&@#$ out of them.



We will find out if these are round enough when I fill the boiler!

I used North American 1/4" tubing for very first run that I made from the boiler to the manometer. The 1/4" is really close to 6mm, but the fittings, well, don't really fit. I was also not particularly happy with the stack of adaptors on the back of the meter, so I swapped it all out for a new 4mm line with a coil to catch the condensation. The nice thing about the 4mm is that it can be bent easily and without much fear of the wall collapsing. I made the coil by winding the tubing around a cylinder by hand.



Here is the line, with the fittings brazed in place (round ones this time) and ready to be installed.



I also wanted to add a tank drain to the plumbing system. I don't really understand why this isn't a more common feature. The HX setup means that the mineral concentration of the water in the boiler is constantly increasing as pure water is drawn off in the form of steam. On the Aurora, a proper boiler flush can only be done by removing the case and disconnecting the lowest convenient fitting, which is the line to the level gauge. What this actually means in practice is that boiler flushes don't get done nearly as often as they should. I built the stainless boiler as a (nearly) drop-in replacement for the copper original. However, I don't intend to build a level gauge as I think that they are vestigial and appendix-like. This means that the ports can be used for something else - e.g. a drain!





That is an ooooold valve. I'll have to find something a little better eventually.

That, I think, is it for now for the plumbing. Here are a few shots of the finished setup.




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markmark1
Posts: 234
Joined: 9 years ago

#143: Post by markmark1 »

Really is a thing of beauty.

Devin H
Posts: 157
Joined: 10 years ago

#144: Post by Devin H »

Keep it up Thomas! Enjoying the posts very much! I can see myself doing something similar once the kids are grown.

andyone
Posts: 30
Joined: 17 years ago

#145: Post by andyone »

stunning! I'm looking forward to the progress! This machine design is worth to make it available for a brighter audience.

Andy

wsfarrell
Posts: 497
Joined: 11 years ago

#146: Post by wsfarrell »

Plumbing newbie here. Could you explain what you mean when you describe "having a coil to catch the condensation"? Thanks!

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Chert
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#147: Post by Chert »

wsfarrell wrote:Plumbing newbie here. Could you explain what you mean when you describe "having a coil to catch the condensation"? Thanks!
+1

I have not seen that in other machines. What would that coil in line to the pressure transducer at the PSTAT do?
LMWDP #198

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bidoowee (original poster)
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#148: Post by bidoowee (original poster) »

The coil in the line to the pressure gauge is something that I have seen a few times elsewhere. I thought about the 'why' for a bit and came up with this: in the original design, the manometer is positioned higher than its connection to the boiler. As the line is necessarily a fair bit cooler than the inside of the boiler the steam will condense into water and then run back down to whence it came. Here however, the gauge is well below the waterline. Once the bottom of the first coil fills with condensate, it (by my hypothesis) will act similarly to a u-bend under a sink, effectively sealing the steam side from the air side.

Why go to the trouble? Possibly because gauges are sensitive to corrosion. No water, no corrosion.

The series of coils may eventually all fill and then spill over into the gauge or it may make no difference whatsoever whether or not the gauge is continuously wetted with (nearly) pure water.

All that said, the surplus length in the coil also makes adjusting the fit much easier...

ira
Team HB
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#149: Post by ira »

bidoowee wrote:The series of coils may eventually all fill and then spill over into the gauge or it may make no difference whatsoever whether or not the gauge is continuously wetted with (nearly) pure water.
Traps are designed to keep gas out and also so they only get so full. If you made it so that when it overfills it drains back to the boiler instead of to the gauge it would do a better job of protecting the gauge. If the coil was horizontal and the bottom coil connected to and was above the boiler connection and the top coil went to the gauge it might be better at protecting the gauge from water.

Ira

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bidoowee (original poster)
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#150: Post by bidoowee (original poster) »

Yes!!! That was what I was missing.
It does assume however that all the steam will condense -before- it gets past the coil.

Any thoughts as to whether the gauge actually needs the protection?