It Worked !!!

My shop is a steel building similar to a quonset hut. The pipes to my bathroom sink run down inside one of the deep corrugations. The
bathroom walls are covered in drywall which in turn is covered with thin sheets of vinyl covered Masonite. I insulated the pipes before covering them with the drywall. I then put insulation down inside the corrugations to insulate the walls. But I think some rodents got into the insulation. Whatever happened when the temp drops below about 30 degrees the bathroom pipes will freeze. I am not eager to tear into the wall to find the problem. So I leave the taps slightly dripping when the weather gets too cold. I now have a little water heater under the sink so that the main water heater is off most of the time. I turn off the under sink heater when the tap is dripping. So my system works except when I forget to leave the water dripping. And I did that yesterday. Coming in to work this morning I discovered the frozen pipe problem. Besides the hassle of no water one day the pipes are going to burst and then I WILL need to tear into the wall. But maybe I have hit on a solution. The water pipes going into the main water heater are connected to each other with a heavy copper wire just before the heater connections. This is to comply with the building code. So I figured if I connected some power to the pipes right at the wall stops I could maybe get them to heat up enough to thaw them. I measured the resistance from stop to stop and it was 4 ohms. The stops are plumbed to the sink taps with plastic pipe so I know the resistance I measured was through the supply pipes. So I plugged in a Variac, plugged my battery charger into the Variac, and connected the battery charger leads to the wall stops. Then I dialed up the voltage until the charger was putting out about 18 amps. Checking about an hour later I see water is now flowing from the taps. So now I need to wire up a transformer controlled by a thermostat to keep those in wall pipes warm. No more dripping taps! Anybody want to tell me why this is a bad idea? Thanks, Eric
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On Friday, February 23, 2018 at 1:47:33 PM UTC-8, snipped-for-privacy@whidbey.com wrote:

Two potential problems: firstly, there's volts applied, and that can accelerate corrosion (of the tank, the pipes, or even buried exterior pipes). Any changes (new water heater, somewhere down the line) can change your circuit, too. Second, the toilet tank/bowl might also be freeze-able.
Me, I wrapped some heat tape around the pipes that get coldest, and I'm happy with that. Tiewraps and an oversheath of snap-on insulation are also applied. That only applies to some crawlspace in my case, but in yours a bit of heat (like an electric thermostat/fan gizmo) could make your restroom more cold-friendly.
Thanks for the reminder! I've just verified that the heat tape is working (drawing power), with a handy Kill-o-Watt. It's something of a comfort to know that the years haven't undone that precaution.
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wrote:

The bathroom doesn't get cold enough to freeze. It's cold coming from the outside that is freezing the pipes. To wrap the pipes I would need to cut open the walls, which I am loathe to do. The pipes I'm energizing don't go underground. And the hot water pipe is shorted out to the cold water pipe before the water heater. So I don't think any power is running through the water heater. Eric
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On Fri, 23 Feb 2018 13:53:08 -0800, snipped-for-privacy@whidbey.com wrote:

Thermostatically controlled pipe heaters start at under $20.
https://is.gd/6QtzdU Amazon
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wrote:

I'm looking for inconspicuous trim screws to replace the tiny ring nails that held on window and door trim I removed to upgrade the insulation. Everything I've found has a head many times larger than the nails'.
If an industrial appearance is acceptable "wafer head" screws may be the answer. http://www.allpointsfasteners.com/WaferHeadSelfDrillingScrews.html
-jsw
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On Sat, 24 Feb 2018 07:21:10 -0500, "Jim Wilkins"

Trim head deck screws might be good there, and they come in colors. Some are self-drilling, others would require a pilot hole for trim to prevent splitting. https://www.strongtie.com/collatedexteriorwoodscrews_collatedscrews/dthq_cscrew/p/trim-head-screw--type-17-point
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On Fri, 23 Feb 2018 13:53:08 -0800, snipped-for-privacy@whidbey.com wrote:

Used to be a common practice to thaw pipes on the farm with the old "buzz-box" lincoln TombStone welder. Set it to a low current ,, connect the cables, turn it on and walk away. You knew the job was done when the water found it's way out of the split pipe - - - -
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On Friday, February 23, 2018 at 9:40:41 PM UTC-5, Clare wrote:

WHen I lived in Huntsville, we lived at the base of Monte Santo Mountain an d the house was sitting on limestone. Unfortunately the water line ran und er the car port and was not insulated. BUt it was metal pipe. So when it was really cold it froze under the cement. And I did pretty much the same thing. Except for using a welder instead of a battery charger. It did not freeze every year so I never made anything more compact. I expect it does not freeze every year where you are, so hardly worth the effort to make so mething dedicated .
Dan
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On Sat, 24 Feb 2018 07:06:48 -0800 (PST), " snipped-for-privacy@krl.org"

It does freeze here every year. Less so on average each year though... Eric
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On Sat, 24 Feb 2018 08:41:50 -0800, snipped-for-privacy@whidbey.com wrote:

We used a welder every day for preheating the discharge pipe on the mag pump. The pipes had welded on tabs just to provide a place to clamp the leads. This was to pump molten magnesium from the collection well in the experimental electrolytic cell into the crucible car below.
I redesigned that pump. The original used air motors, angle iron frame, about a 6' shaft to the impeller with graphite bearings every couple feet. I went with a shaft tapered from 2" to 1/2", no bearings, and a belt drive to eliminate an in-line connection to the motor. Eliminated most of the maintenance.
That's the first time I ever saw a taper attachment. I had designed the shaft with a series of steps, and the shop guys called me over and asked if a taper would do, since it was a lot easier to cut with the taper attachment. Designing stuff, then getting to spend time with the machinists in the shop was where I really got the bug.
Pete Keillor
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On Sun, 25 Feb 2018 20:24:12 -0800, Larry Jaques
snip

He's lucky he checked his water bill - - - -

Too cool to mold - and drycore and the carpet tile he used are mildew resistant. A bit of mildew/mold on one piece of "termite spit" shelving.

Shrink the oratex fabric on the plane.
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wrote:

Again, very lucky.

Oh, so that's how the fabric airplane wings are fashioned. I've often wondered.
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Before metal construction took over full-sized planes and balsa models were built about the same way. http://hawkerrestorations.co.uk/
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On Tue, 27 Feb 2018 13:22:10 -0500, "Jim Wilkins"

I'd seen the old kits with fabric and dope back in the '60s, but never shrinking fabric, at least for kits.

Wow!
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On Tue, 27 Feb 2018 08:58:01 -0800, Larry Jaques

Even the old type of classic fabric covering like Stitts etc uses heat - but google oratex and get an education on the NEW way to fabric cover a plane!!!. No dope, no sealer, no aluminum to sheild against ultra-violet. No stink and no overspray - no explosion or fire danger while installing.
About twice the price, and worth every nickle!!!
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wrote:

Yeah, a whole lot less work, too, I'd imagine.
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wrote:

The old unshrunk cotton fabric was replaced with polyesterf fabric - again unshrunk - which was heated to do the initial shrink, then shrunk further by applying nitrocellulous dope - terribly nasty and flammable stuff - then usually covered with a butyrate dope for durability and protection - with several coats of aluminum filled dope to fill the weave and protect against ultraviolet. before the final color coats.
Youcould make the fabric glass smooth.
The oratex is a single step covering - precolored - no extra coating required - but does not give the mirrorlike show finish of a doped fabric.
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wrote:

Oh, the dope shrunk it? I'll have to file that, too. Friends' dads did larger models and doped them. Stee-inky. "Get out of here, kids. This stuff will make you lightheaded."

To me, dat's mo betta, 'cuz the less glare, the better.
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On Thu, 01 Mar 2018 22:01:53 -0800, Larry Jaques
snippp

But your "hangar queen " HAS to glow!!!!
On a bush plane as long as it keeps the wind and blackflies out, you're gold!
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wrote:

So wax your ego, already. <g>

Perzactly. Well, that and land on a dime and take off on a quarter. I'd love to get my hands on a well prepped SuperCub with the B17esque tires and flexi landing gear, etc. But I'd hate to traverse any long distances at a cruise speed of 60mph.
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