Inqism-05: The Throne Room

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Jimmyt
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Re: MX-5: The Throne Room

Post by Jimmyt »

Inquisitor wrote: Wed Jan 13, 2021 3:07 pm
Thanks JimmyT for the keyword. I YouTube'd a few and tried it out. Turns out I need 6" radius. With the veneer grain going vertical, it was too stiff, but probably could be bent with some water soaking. With the veneer grain going around the circumference, it was almost too limp. Easily makes a 5" radius without having to tie it down, but with a maximum of 4' tall, I'll have to do two pieces for the door. Maybe some kind of accent strip between them.

Word for the day! - Kerfing! 8)
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Nice!
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Re: Inqism-05: In HOT Water

Post by Inquisitor »

Jimmyt wrote: Wed Jan 13, 2021 5:12 pm Image

This is a good way to do it if you can set a temp that everyone is happy with. You'll have a single valve to deal with at the shower. Very simple. Our locker room in high school was designed that way. The water temp was whatever coach decided. We could only turn the showers on and off.

Using unpressurized sources, one problem may be the pressure drop of the mixing valve. You normally need to have enough elevation (head) to overcome the valve pressure drop at the required flow for both hot and cold sources to stay out of NPSH issues. However, if you use a positive displacement pump, you may have a better chance to suck the water through the valve, up to a point. If you have to pull it too hard, the water will vaporize at the valve, and the pump suction. It shouldn't be a problem unless you mount the tanks very low and the pump high. Since I don't know the characteristics of your valve, or your proposed configuration, I'm only able to give you a "this is a potential problem" heads up. May not be an issue.

It would be better to pump the hot and cold into the mixing valve (requires two pumps). But, you can try it and see how it goes. You can put a pressure gauge at the pump suction and see what you've got.
I'm glad I asked. :?: I've seen them in the shower in cruise ships, but don't really know much about them. All that mechanism must cause a pressure drop and I wanted to put it in the shower about waist high which is another pressure drop. Don't know how much these RV water pumps can tolerate. :(
Last edited by Inquisitor on Fri Jan 22, 2021 6:51 am, edited 2 times in total.
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Re: MX-5: The Throne Room

Post by Jimmyt »

Inquisitor wrote: Fri Jan 15, 2021 5:34 am
I'm glad I asked. :?: I've seen them in the shower in cruise ships, but don't really know much about them. All that mechanism must cause a pressure drop and I wanted to put it in the shower about waist high which is another pressure drop. Don't know how much these RV water pumps can tolerate. :(
If you put the tanks low, and install the mixing valve at waist height, then put the pump low; you will have a hard time getting it primed when new, or anytime the system gets dry. But, if you put a pump/accumulator at each tank, it should work just like the cruise ship.

Also, if you use flex tubing, it wouldn't be difficult to mock up the system and check it. You'd just need to test the configuration on the suction side. The pressure side should be fine. I'll look today and see if the pump info has any useful performance data.
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Re: MX-5: The Throne Room

Post by Jimmyt »

Is this what you're thinking?

Image

My pump info had zero useful performance data... :?
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Re: Inqism-05: The Throne Room

Post by Inquisitor »

Jimmyt wrote: Fri Jan 15, 2021 9:22 am Is this what you're thinking?

Image

My pump info had zero useful performance data... :?
Schematically perfect! 8)

I imagine heights and run lengths might be significant. So for key locations:
  1. Cold Water Tanks - I'm liking the idea of multiple collapsible 5 gallon containers like the original "Mac tank". They'd be at a little higher point on top of the ballast tank.
  2. The Galley sink (TBD published) will be forward of the head. This way all the water users are right next to each other. Something like this at the standard kitchen cabinet height of 36".
    Image
  3. Mixing Valve would be on the common wall with the dial on the inside of the head.
  4. Pump will be low in the cabinet under the galley sink. Basically on the floor under the M's table. Plenty of room around it to work on it and sound insulate it.
  5. Hot Water Tank - In the head built-in using fiberglass and sheet foam for insulation/forming. It'd be on the hull wall since you can't stand there anyway. It'd be easy to fill with the cold water shower head and drain directly into the mixer valve.
Last edited by Inquisitor on Mon Feb 01, 2021 5:11 am, edited 3 times in total.
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Re: Inqism-05: The Throne Room

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Anyone have any direct recommendations for a showerhead? I'd like one that has:
  • Low volume < 1.5 gal/min.
  • Still sprays decently even with low pressure (30 psi)
  • Shut-off/on valve on the head. I would prefer it to be a press and hold to run. Don't want to waste water. Unfortunately any one I've every used the valve was a joke and dribbles. Besides... they also stay on.
So far, I'm looking into something like:
https://www.ebay.com/itm/Stainless-Stee ... 1438.l2649
Image
Last edited by Inquisitor on Fri Jan 22, 2021 6:50 am, edited 2 times in total.
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Re: MX-5: The Throne Room

Post by Jimmyt »

Inquisitor wrote: Fri Jan 15, 2021 12:30 pm So for key locations:
  1. Cold Water Tanks - I'm liking the idea of multiple collapsible 5 gallon containers like the original "Mac tank". They'd be at a little higher point on top of the ballast tank.
  2. The Galley sink (TBD publish in MX-6) will be forward of the head. This way all the water users are right next to each other. Something like this at the standard kitchen cabinet height of 36".
    Image
  3. Mixing Valve would be on the common wall with the dial on the inside of the head.
  4. Pump will be low in the cabinet under the galley sink. Basically on the floor under the M's table. Plenty of room around it to work on it and sound insulate it.
  5. Hot Water Tank - In the head built-in using fiberglass and sheet foam for insulation/forming. It'd be on the hull wall since you can't stand there anyway. It'd be easy to fill with the cold water shower head and drain directly into the mixer valve.
So, if I get your meaning, the arrangement is more like this:

Image

I like the fact that it keeps the hot line short, minimizing heat loss in the piping.

Now, the gravity flow into the valve from the hot tank, and a long suction line to the cold tank, which is mounted about 3 feet below the valve, is not an optimal arrangement for good control. It will be interesting to see how it works.

I looked up several of the thermostatic valves, but couldn't find any real data on them.

I have only worked with a couple of systems that had very different pressures entering ports on a symmetrical mixing valve. Tends to make control a bit interesting. The mixing valve will have to almost close the hot water port to get flow from the cold tank. It should work, theoretically, even if not ideal. That is, if you can keep the pressure drop reasonable in the cold line, and if you can get the cold line to prime... You definitely have some interesting projects in the works! :D

The good thing about tubing and clamps is, if it doesn't work well, it's easy to reconfigure.
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Re: Inqism-05: The Throne Room

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Jimmyt wrote: Fri Jan 15, 2021 4:50 pm So, if I get your meaning, the arrangement is more like this:

Image
I'd say... very accurate. :o

Image

Here, I've just added the approximate numbers. The "plus" numbers next to items are the heights above the pump. The color numbers are lengths between the two connected items.

I'm guessing this mixer valve is the biggest unknown. I've one ordered... ETA 2/1. Details say it works with water pressures between 0.1Mpa-0.5Mpa (15 and 70 psi). It also says something about "Dynamic Pressure" = 0.3 ± 0.02 Mpa (40 - 46 psi). Don't have a clue what that is. :? Hope that doesn't mean I'm out of luck with my pump only delivering 30 psi.
Last edited by Inquisitor on Fri Jan 22, 2021 6:49 am, edited 2 times in total.
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Re: MX-5: The Throne Room

Post by Jimmyt »

Looked up a "real" TMV just to have some flow characteristics to work with. This company was my go-to solution in my former life... At any rate, gravity flow, or suction line (cold) location may not give you the necessary pressures to work with, unless the pump can pull a 0.5 bar vacuum. Since you are using a positive displacement pump, it may happen. But, don't permanently mount the pump until you test it.

You are basically at zero inlet pressure on the hot side of the valve (tank head only), and under a vacuum on the cold side inlet.

Look at the smallest valve they offer (lowest curve). They recommend 1 bar minimum operating pressure. If your pump could produce a one bar vacuum at the valve, the water would turn to steam in the tubing (water boils at 75 deg F when the pressure drops to around 0.5 psia- if my foggy memory is in the ballpark).

Image

Maybe the knockoff version has a lower pressure differential requirement... but, I wouldn't count on it.

I would still mock it up and test it in your configuration. Since the valve is basically an unknown, it may work. Just don't do any permanent install until you try it.
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Re: Inqism-05: The Throne Room

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Jimmyt wrote: Sat Jan 16, 2021 6:01 am Looked up a "real" TMV just to have some flow characteristics to work with. This company was my go-to solution in my former life... At any rate, gravity flow, or suction line (cold) location may not give you the necessary pressures to work with, unless the pump can pull a 0.5 bar vacuum. Since you are using a positive displacement pump, it may happen. But, don't permanently mount the pump until you test it.

You are basically at zero inlet pressure on the hot side of the valve (tank head only), and under a vacuum on the cold side inlet.

Look at the smallest valve they offer (lowest curve). They recommend 1 bar minimum operating pressure. If your pump could produce a one bar vacuum at the valve, the water would turn to steam in the tubing (water boils at 75 deg F when the pressure drops to around 0.5 psia- if my foggy memory is in the ballpark).

Image

Maybe the knockoff version has a lower pressure differential requirement... but, I wouldn't count on it.

I would still mock it up and test it in your configuration. Since the valve is basically an unknown, it may work. Just don't do any permanent install until you try it.
WOW! This is a test...Right? Its been one hull of a long time since I've had to cold interpret a graph. :D Had to load that capability off a tape drive, with the tape on the cob-webbed shelf. I'm surprised that brain cell is still with us. BUT, my take aways...
  • At most, I'm only flowing 7.5 L/min, so well down in the trash area at the bottom of these curves.
  • Of course, these Valves are used to having differentials, far greater than 1 bar as their design spec.
  • An aside - We could have ruled the world if we had the Internet when growing up!
  • Just checked ShurFlo priming height - 12 feet. I find that number highly dubious, but on face value that's says the best differential this pump can create is 0.29 bar...
  • That's to the left of the lowest value these valves know how to deal.
Net-net - This idea isn't going to work.
No biggy! I'll breadboard it, just for grins, but I can always use the valve in the house. The Admiral and I have a tug-of-war on the temperature. At least this way, I can check the setting and won't get scalded.

On to Plan B...
Last edited by Inquisitor on Fri Jan 22, 2021 6:49 am, edited 2 times in total.
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Re: MX-5: The Throne Room

Post by Jimmyt »

While they recommend 1 bar differential, they show performance at 0.5 bar. The fact that Shurflo says the pump will prime at 12 ft is encouraging also. Wonder how many batteries it takes to pull a 12 ft prime? :o

A lot of time, you're probably in between 3 and 7.5 l/ min, so the numbers are close.

I wouldn't try it for a paying client. But, its close enough where I can't say it absolutely won't work. (Is that enough negatives for you?) :wink:

I knew you would mock it up. Only problem is, now I'm going to have to wait till February to find out if it will work... :cry:

Party on, Garth!
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Re: Inqism-05: French Press

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Some time ago, I started using a French Press for my coffee habit. I liked the idea that I could make it stronger than just passing it through a Mr. Coffee Maker once. It needs a little quality time in those grounds. As a side benefit... running out of filters is no longer a life threatening experience.

Image

... or is it? ...

The throne has arrived and the first thing I pull out... Did you guess?

Coffee Filters - Is this some conspiracy? Is there a connection between coffee and going Number 2? Inquiring minds want to know. 8)

Image
Last edited by Inquisitor on Fri Jan 22, 2021 6:49 am, edited 2 times in total.
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Re: MX-5: The Throne Room

Post by Jimmyt »

That surprised me at first, also. I was watching videos on toilet solutions and someone mentioned using coffee filters for anti-skid mark duty. I thought, sounds weird, but a good idea...
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Re: MX-5: Refining the Numbers

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We here in the mountains had a small reprieve the last two days. We have beautiful sunshine and highs finally get into the mid 50's by mid-afternoon giving me four or five hours of boat time. This is definitely at my lower limit to be doing boating and/or outdoor projects, but if I want to get it in the water in the spring, I'll need to toughen-up buttercup.

Demolition
Not really demolition... it was mainly removing my 2010 cabinetry on the starboard side. That didn't take that long, but a few places I needed to get out the cut-off grinder and I had forgotten how much crap that throws up in the air. I've order new Tyvek, goggles, respirator and filters to do the major surgery to come.

Level Up
Also in that time, I needed to level up the boat. At my house, I have NO level ground... the closest... hmmm... might as well be Kansas. It took most of the sunshine day. Lift one corner or another, put blocks, pieces of wood, whatever, lower the jack and measure. There is a lot of flex in the boat/trailer even in the small distances between blocks and jack. I used the hull lines on the sides with a 4' level and used the cockpit area just behind the traveler for side to side. Surprisingly, I could not get both sides perfectly level front-to-back. How does that happen? And side-to-side, I was down to using 1/4" shims... which screwed-up the front-to-back again. Point being... it took a while! Once that was done it was a simple matter of using a laser level to scribe lines around the inside for the seat and cabinetry height I want to be as level and consistent as possible around the cabin.

Scoping the Throne Room
I think, I'm really going to like this setup... better than my 2010 version and certainly better than the stock Head space. I was able to bring the AirHead into the boat and place it in the desired location and take final measurements. I was thinking it would be close, but it turns out its dead-on... While perched, my eye level is exactly mid window height. I can now contemplate the wonders of the universe and at least see the starboard quarter horizon. :)

My estimates were pretty close, but have now been confirmed with a level boat and marking finished floor height.
  • Flat, level, unobstructed floor space 23" x 26.5"
  • Hip height area, 34" x 41.5"
Image

Today, boredom has set in (Dah... right?) It's snowing again. But, I think I've found an indoor project to fill this time that I can't be on the boat.
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Re: Inqism-05: The Throne Room

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Well I have all the pieces in to test run the system. I started testing it outside, but really... at 35F playing with water is not enjoyable. Funny how the Admiral frowns on my squirting water in the house. I simply hooked up the bare minimum. I wanted to get a baseline before I put the mixer valve on the input side.
  • 12V deep cycle battery
  • Bucket filled with water.
  • 6' hose
  • Whisper King, 30 psi, 2 gal/min pump
  • Accumulator tank
  • Bidet Sprayer
Image

Image

Per JimmyT's suggestion, I set the accumulator pre-charge to 15 psi. It was set at 30 psi.

It was pitiful! :(
With all the gear on the ground and the sprayer aimed horizontal at 5 feet up, it sprayed out and hit the ground about 3' away. PITIFUL! Checking the pressure once the pump cut-out (pressurized) it read only 20 psi. The pump is old, but still whisper quiet as advertised. Its simply not going to cut it.

Can I get anyone's input of the pump you have and your experience with it? Things like pressure, flow rate, sound level... does it wake you up in the middle of the night kind of thing??? I'm thinking I'd like something closer to house pressure, but I'm not sure what common is. My last house was above 100 psi. This house is 70 psi. What's realistic for a boat water pressure system?
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