I am considering constructing a storage container, for thermal storage(unpressurized), similar to our hot tub. The hot tub is circular in shape, made of 2x6 western red cedar, held together with metal rings and holds approximately 650 gallons of water. There is no liner. The cove and bead edges of the wooden slates coupled with natural swelling of the wood keeps it from leaking. We have enjoyed the tub for the past 8 years and it has held up quite well. The only difference will be the water temperature. As a hot tub the water is rarely warmer that 102 degrees compared to the 180 degrees as thermal storage for the heating system. I would think it wood would be a better insulator.I am not sure if it will hold up to the temperature. Does anyone in the "room" have any thoughts? Thanks for the help.
Wooden Storage Container without a liner ?
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Singed Eyebrows
Minister of Fire
If nothing else you'd have a nice warm hot tub. Seriously though I don't believe the wood will hold together for any length of time. Randy
Gooserider
Mod Emeritus
Might work, but I'd worry about the wood breaking down at the higher temps. Also it seems that most of the home-built (and commercial) non-pressured systems put most, if not all, of the insulation on the inside of the shell, presumably because that works better - though it might be cosmetic. Seems to me like the liners are as much to keep the insulation dry as they are to keep the water in... I would also point out that while wood is a better insulator than metal, it really isn't all that good, nor is it all that water-tight...
In your hot tub, you wouldn't notice any leakage through the wood because you probably lose far more from splash-out, evaporation, and so forth, but over time it would probably be a significant amount - I know that breweries that age their product in wooden casks do loose a certain amount (known as the "Angel's share") every year from evaporation through the walls of the casks... However my understanding is that a lined tank w/ a tight fitting lid, and with a layer of parafin or oil on top of the water, will have just about zero loss to evaporation.
If you look at the R-value of wood, it is low enough that even in a fiberglass insulated wall, the studs are considered a significant heat loss path - which is why you get a big improvement by covering a wall w/ foam as it breaks up that conduction path - but you want your storage tank insulated to a much better level than any standard 2x? wall...
Gooserider
In your hot tub, you wouldn't notice any leakage through the wood because you probably lose far more from splash-out, evaporation, and so forth, but over time it would probably be a significant amount - I know that breweries that age their product in wooden casks do loose a certain amount (known as the "Angel's share") every year from evaporation through the walls of the casks... However my understanding is that a lined tank w/ a tight fitting lid, and with a layer of parafin or oil on top of the water, will have just about zero loss to evaporation.
If you look at the R-value of wood, it is low enough that even in a fiberglass insulated wall, the studs are considered a significant heat loss path - which is why you get a big improvement by covering a wall w/ foam as it breaks up that conduction path - but you want your storage tank insulated to a much better level than any standard 2x? wall...
Gooserider
Over the years during my past career with papermills, I have encountered very old wood stave tanks that had been in service for many years (40 to 50), that held very hot "white water" from papermachines. The big issue with them was to keep them wet all the time. Unless the whitewater had some preservative effects, I expect that a wooden tank would hold up for a quite a long time, although I expect that it acts as a humidifier where ever it was stored.
Fred61
Minister of Fire
I contacted a company that manufactures wooden water tanks last year and they told me that the wood would break down quite rapidly at the hot water storage temperatures. Incredibly there are still thousands of water storage tanks being used and many new installations on high rise buildings in places like NYC.
Obviously there are two opinions via what has stood the test of time and what has not. For those who say it won't last there is a need to look at those tanks that have. There is/are probably (a) certain type(s) of wood that will work since some tanks have withstood high heat for such a long time. Maybe high resinous dense wood or wood like locust that people have used for fence posts for a long time. Beech is a hard wood that has been used in water/fluid storage. I think the water treatment for ph could be an undisclosed element and the high heat would basically eliminate bacterial break down of the wood.
Wood is actually a poor insulator. Wood on average has about R1 per inch. Wet wood has little or no insulation value.
A buddy of mine is a forester, I'll ask his opinion on what would happen to the cellulose cell structure of wood at the temps we use.
A buddy of mine is a forester, I'll ask his opinion on what would happen to the cellulose cell structure of wood at the temps we use.
Fred61
Minister of Fire
Cave2k said:
It even goes deeper than a specific species of wood. The tank manufacturer I talked with even uses only the heartwood of the species he has chosen for the application. I can't recall all of the conversation but I know he mentioned that he uses several different species. I think that one of the ones he mentioned was douglas fir. I think it all boiled down to how much you wanted to pay for the length of the working life of the vessel.
tom in maine
Minister of Fire
White Oak is an excellent wood for barrel construction.....Not sure why you want to build a storage container this way...esthetics? Awful lot of work and money and for only 6 or 7 hundred gallons.....I think foam construction block would maybe make a good container....inherent R value plus you could then super insulate it with batts.....then box it again if you want with cedar...could look like a nice little building....suitable for a dwarf......I think the big thing is to insulate...your tank...your house...keep the heat...I super insulated our hot tub....was in it 30 hours ago..in at 102 degrees for about 30 minutes then covered it... just checked temp. and it was at 95 degrees still without any heating....nighttime temp. of about 37 or so degrees ...I'm putting in boiler infrastructure soon...going to excavate an underground room...pour footings then do a pressure treated foundation...metal pan it for 5 or so inches of concrete....not sure about tank construction..maybe block but I'm leaning towards a log tank...SM styrofoam inside then a geomembrane liner....styrofoam outside it then batt insulation...want all my plumbing etc. underground..
boiler building above.....been putting in the pipe the way a friend did...5 ft. deep trench...sand base then styrofoam encased 3 in. pvc sewer pipes..then sand/soil backfill....gentle sweeps if you must make turns....that way you can fish tape it and pull your pipes through...ever a problem you can pull them out and replace.....luckily he has a 600 ft. tape...expensive but you could rent or hire someone to fish and pull your ropes through...to replace you just tie a rope to the pipe so you can pull the new through....I run my water lines to outbuildings and hydrants this way or I lay in double or triple the pipe or wire I'm running...everything eventually breaks down or wears out....Have fun..............
boiler building above.....been putting in the pipe the way a friend did...5 ft. deep trench...sand base then styrofoam encased 3 in. pvc sewer pipes..then sand/soil backfill....gentle sweeps if you must make turns....that way you can fish tape it and pull your pipes through...ever a problem you can pull them out and replace.....luckily he has a 600 ft. tape...expensive but you could rent or hire someone to fish and pull your ropes through...to replace you just tie a rope to the pipe so you can pull the new through....I run my water lines to outbuildings and hydrants this way or I lay in double or triple the pipe or wire I'm running...everything eventually breaks down or wears out....Have fun..............
Gooserider
Mod Emeritus
One trick that can be used for fishing stuff through long lengths of conduit is the suction and / or blow approach - it is often used by people needing to fish telecom cable through conduits, and can be used in all sorts of other applications...
Equipment -
1. Good shop vac (must have high volume as well as good suction), and / or high volume, moderate pressure compressed air source - really long runs or big bore tubes could use both.
2. Roll of poly or nylon "masons string", or similar. I like mason string because it's very strong for its size, and it dispenses very nicely of the spool. Must be at least as long as the pipe run.
3. A "puff" - some sort of soft, easily deformable item that will fit loosely inside the pipe, so that it will slide through easily, but block most air flow around it. On small pipes a wad of paper towels works well, I've also heard of people using chunks of soft foam (think something like a "Nerf" ball) The tighter the fit the better, but the puff MUST be free to slide, so don't get it overly tight...
4. Means of connecting the pressure / suction source in #1 to the pipe, and sealing around the end - could be as simple as your hand, or something like a bunch of rags, depends on the relative sizes.
Technique -
1. Attach puff to end of string
2. Stuff puff into one end of pipe
3. Hook vac to other end of pipe, and / or pressure to the same end, turn on...
4. Catch puff as it comes out other end... (Note, if using a vac that is bigger than the pipe, check often, as it is really easy to suck up the puff and a LOT of string before you know it... (Don't ask how I know... :red: )
5. Use string to pull the content, or if needed a heavier intermediate pull rope.
If I'm going to be making multiple pulls in the same conduit, I will often make my pull string twice the length of the run, plus a bit extra. I then tie each end to a solid anchor, and attach the pull in the center of the string - I can then just shuttle the middle of the string back and forth for each pull. When I'm done, I will just make a little bundle of the extra string and leave it in place in case I ever need it for future use.
This is MUCH cheaper and easier than dealing with long fish tapes...
Gooserider
Equipment -
1. Good shop vac (must have high volume as well as good suction), and / or high volume, moderate pressure compressed air source - really long runs or big bore tubes could use both.
2. Roll of poly or nylon "masons string", or similar. I like mason string because it's very strong for its size, and it dispenses very nicely of the spool. Must be at least as long as the pipe run.
3. A "puff" - some sort of soft, easily deformable item that will fit loosely inside the pipe, so that it will slide through easily, but block most air flow around it. On small pipes a wad of paper towels works well, I've also heard of people using chunks of soft foam (think something like a "Nerf" ball) The tighter the fit the better, but the puff MUST be free to slide, so don't get it overly tight...
4. Means of connecting the pressure / suction source in #1 to the pipe, and sealing around the end - could be as simple as your hand, or something like a bunch of rags, depends on the relative sizes.
Technique -
1. Attach puff to end of string
2. Stuff puff into one end of pipe
3. Hook vac to other end of pipe, and / or pressure to the same end, turn on...
4. Catch puff as it comes out other end... (Note, if using a vac that is bigger than the pipe, check often, as it is really easy to suck up the puff and a LOT of string before you know it... (Don't ask how I know... :red: )
5. Use string to pull the content, or if needed a heavier intermediate pull rope.
If I'm going to be making multiple pulls in the same conduit, I will often make my pull string twice the length of the run, plus a bit extra. I then tie each end to a solid anchor, and attach the pull in the center of the string - I can then just shuttle the middle of the string back and forth for each pull. When I'm done, I will just make a little bundle of the extra string and leave it in place in case I ever need it for future use.
This is MUCH cheaper and easier than dealing with long fish tapes...
Gooserider
Thanks to all of you for taking the time to share your advice and experience, it is much appreciated.
Enjoy the weekend and..........remember your mom.
Enjoy the weekend and..........remember your mom.
flyingcow
Minister of Fire
That was my fault...yes good advice. Makes me think of the vacuum/blower(?) tubes you can still see in stores or factories...tube with invoice or whatever travels through a pipe.....
Gooserider
Mod Emeritus
Btwncentres said:
Exactly the same idea, just a "one shot" use, and with a string tied to the package so you can pull with it... IMHO a lot simpler approach than trying to get a long fish tape, and really dirt cheap to do.
Gooserider
hmmmm...my friend does underground line and whatever work....His daughter works for him and was complaining of fishing 100 and something pipes..big fibreglass fish tape...in just a couple of days...he has a mobile compressor...would take a big vacuum ..no?....
This is what goose is referring to Greenlee Mouse System
You can buy the individual mice at an electrical supply store for a couple bucks each. A shop vac and a piece of cardboard makes a good seal.
Us electricians use it all the time with long conduit runs. For smaller pipes you can even use a piece of a plastic bag to make a parachute of sorts.
We have used it on as large as 4" pvc with 500 foot runs with the small masons string, then we tie mule tape on and pull that through.
You can buy the individual mice at an electrical supply store for a couple bucks each. A shop vac and a piece of cardboard makes a good seal.
Us electricians use it all the time with long conduit runs. For smaller pipes you can even use a piece of a plastic bag to make a parachute of sorts.
We have used it on as large as 4" pvc with 500 foot runs with the small masons string, then we tie mule tape on and pull that through.
rowerwet
Minister of Fire
a venturi vacuum would work with a compressor, it would use up a lot of air though, with a compressor you might do better to blow than suck.
Gooserider
Mod Emeritus
seige101 said:
Exactly - that's just the expensive commercial version... The mason string and improvised puff approach may take a little longer, but is cheaper... Maybe a buck for the string, negligible for the puff. Last time I did this, we used a small wad of paper towels (about 1/2 sheet), and a relatively low power shop vac. But it was a relatively small run ~50' or so of 3/4" NMT.
As to size and whether it is better to suck or blow, I would say that it is a question of getting the right fit on the puff, or mouse, which might get tricky, and how long the run is. Essentially the critical issue is to overcome the drag of the puff and the string... On a larger pipe the drag would tend to be greater, and so would the leakage, which reduces the useful pushing force. A longer run will obviously have more drag from the string.
Thus the bigger / longer the run, the more potential advantage there might be from using a manufactured mouse to get a tighter, more precise fit. Also there are fairly low limits on just how much force you can get with a shop vac - in theory the absolute most you can get is atmospheric pressure (14.7psi at sea level), and actual practice will be a small fraction of that. Thus for more demanding pulls, you might be better to use an air compressor as that pushes the limits up to the pressure limit of the conduit - FAR more than should be needed...
Gooserider
flyingcow
Minister of Fire
flyingcow said:Gooserider said:
Hey Goose... you ok? I think you misposted.....But its good advice
didn't read the whole post, skimming.........whoops. I've done a little bit of pulling strings with a shop vac. Works really slick, don't over think it.
rowerwet
Minister of Fire
I have used a shop vac to test the leaks in a pressurized airplane, pretty amazing how much pressure a regular old shop vac can put out and how much the fuselage "grows" under pressure, and then to think that we didn't hit the max differential pressure for the fuselage despite how much it grew. The growth up at 12-20k feet where the air is thinner, must be incredible! (average cruise height for pressurized piston aircraft)
Wallyworld
Member
Btwncentres said:
Electricians blow mice through pipes also. you can buy foam plugs(called a mouse) for most pipe sizes. I use a piece of a plastic bag tied to a nylon string often. if there is water in
the pipe it won't work to well. Leave the vac on the pipe for awhile to get rid of the water before trying
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