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Started by grouch, April 30, 2017, 01:07:10 PM

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grouch

Hmph. She'll more likely give me lunch meats and chips until she has a greenhouse that looks like this. She had my son and I running out into the boonies 40 miles away to bring home a dinky HF greenhouse she found on craigslist for $25 (about a tenth what they sell for new). I told her that was too much, but she had to have it. It was almost intact and complete, but even she agrees it wasn't worth the time or gas. She just stores flower pots in it now.

If this doesn't get hot enough for a kiln, I'll just rip the black plastic off the inside and move it where ever she wants it.

If it does work, I'll still have to build one for her. ;)

Quote from: Darrel on May 17, 2017, 04:23:59 PM
All I can say is that you had better get your drone forwarder fired up and sticker stacking lumber in there before your wife comes back loaded down with flower pots and the like.  :D D D D D

Troublemaker! It's all your fault.
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grouch

I couldn't stand it. There was sunlight hiding behind the corner of the barn in the morning and behind a cedar tree late in the afternoon. So I loaded up my trap and I moved to sunny fields.



Cedar tree had to give the sun trap a little goodbye hug:




Hmm. Maybe I should put my mill in that, put canvas over it and go mobile. Think the D.O.T. would be thrilled to see me?

Guess it would need either Conestoga wagon wheels or Michigan Logging Wheels instead of those dinky 12s.



It will be hotter to put the plastic on there, but the whole idea is to capture heat. There was too much getting away where it was before.
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Darrel

For your sake (and mine too), I hope it is far enough away and hot enough so that your wife will leave it alone. Then my jinxing will be counteracted and I will once again be able to sleep at night.
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

grouch

It should be hot enough where it's at. But you don't get off that easy. She saw where I parked it and said, "Is that for me?"
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Darrel

1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

grouch

Between thunder showers and thunder storms passing through today, I managed to block the contraption up at the 4 corners and get the trailer out. The lowest corner is sitting on a dry stack of concrete blocks 3 layers high. That's 22-1/2 inches. I measured the height of the engine on a push mower and it's 17 inches. I should be able to keep the grass under the platform mowed so that if this thing is a complete flop, I can take it down and not have a big bare spot in the field.

Looking at it, I'm wondering if maybe a better design would be to have semi-circular arches oriented north-south. The north end of the half cylinder would be elevated to an angle matching the latitude. The platform on which the lumber is stacked would remain level. The inner wall of the half cylinder would be black and the outer wall transparent. From sunrise to sunset, the sun's rays would be nearly perpendicular to that inner wall -- passive tracking.
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grouch

Oh, almost forgot.

Quote from: Darrel on May 18, 2017, 05:59:27 PM
For your sake (and mine too), I hope it is far enough away and hot enough so that your wife will leave it alone. Then my jinxing will be counteracted and I will once again be able to sleep at night.

Sleep easy, Darrel. I'm sitting here eating a t-bone steak. If she's gonna try to butter me up to get that kiln for a greenhouse, I may owe you.  ;D
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Darrel

Quote from: grouch on May 19, 2017, 04:30:45 PM
Oh, almost forgot.

Quote from: Darrel on May 18, 2017, 05:59:27 PM
For your sake (and mine too), I hope it is far enough away and hot enough so that your wife will leave it alone. Then my jinxing will be counteracted and I will once again be able to sleep at night.

Sleep easy, Darrel. I'm sitting here eating a t-bone steak. If she's gonna try to butter me up to get that kiln for a greenhouse, I may owe you.  ;D

Now I can enjoy my BBQ chicken and sleep. Thanks.
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

grouch

The sun trap has settled into its new nest in the field.

Up on blocks and the little trailer out from under it:


Got so hot while I was working on it that I decided to add some shade:


See those clouds in the background? Knew it was too hot. Had to go release that big blue sail because nothing anchors that contraption to the ground.

Following the wind came the rain:

There are squirrels who travel across my garage, through a redbud tree to the right, into and then down the walnut tree just left of center, and across the ground to a bird feeder hanging in a grapevine at the left edge of that photo. The little black dog thinks it is his duty to get the squirrels. He outran 1 so far and is determined to get the rest.

After the off-and-on showers, nice and cool this morning:


Such artistry! People pay big money to see wrinkles like those, don't they?
The black plastic was kind of raggedy so I put it on in 3 strips, eliminating the biggest tears.


Don't know if these ~3/4 inch holes will be significant or not:


And it was clouding up as I came in for lunch, so...


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grouch

I screwed up. Got two rolls of 6 mil plastic, 10 ft (ha!) x 25 ft, but they are closer to white than clear. Don't have any confidence in them being more transparent to IR than they are to visible light, so I ordered a 54 inch x 75 ft roll of plastic that's reputed to be clear as glass. ~$60.

"Cheap" just keeps getting whittled away. I think I'm going to be close to $300 for about 500 cubic feet of enclosed space.

Well, there are other things that can be done while waiting for delivery. I'll just have to keep that tarp on until then. It got hot in there very quickly in spite of cool breezes and cloudy sky.
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grouch

Need to bring this up to date. Will post photos later.

Hit 128F by 11:11 am this morning. Had to rescue my remote temp probe because it's only rated for 120F. Was 76F in the shade at the time. The outside layer of clear plastic doesn't even come all the way down -- it's open to the outside -- so it is heating even with sucking outside air into the space between layers of plastic.

Now I need to worry about it melting the black polyethylene, which is drooping really badly right now.

More later.
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grouch

Switching from barely translucent polyethylene plastic at 10 ft wide to very clear vinyl at 54 inches wide required some changes.

The only long (about 14 ft) 2x6 I was able to salvage from my stinky oak had to be sacrificed to make tack strips for the narrower plastic.





This little critter was waiting when I pulled the tarp off:


Treefrogs don't need to be cooked in a kiln, so I moved him to an old apple tree.

Each tack strip is let in so that meant more pilot holes and screws. I cut the notches with a hacksaw to keep from dulling any teeth on a wood saw. Mark, drill x 2, screw x 2, cut, clamp, drill, screw, and repeat for 4 strips on 3 arches.




Weather made it more appropriate to work overnight.

That black plastic on the ridge is there to keep the raw edges from wearing through the clear plastic when it gets installed.



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grouch

In the light of day:


Those tack strips were too thin to be spanning 5 ft and holding plastic flapping in the breeze, so I added strongbacks to them, swiped from my too-small pile of stickers.


Ok, so it's not a real consistent cut. It made 'em stiff enough for the job.



There's a bit of figure in that oak:


Wish I could've salvaged enough to make something pretty from it.





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grouch

The roll of clear plastic was sold as "4 gauge". I have no idea what gauge they use (US Steel? Brown and Sharp? AWG? Railroad?) but it feels like about 4 mil (whatever that is).



I got it through Amazon. It arrived from:


Clear enough for me:


My tack strips are on 48 inch centers. The plastic is 54 inches. Gives me 6 inches for folding to reinforce where it gets stapled. So, fold it under 1-1/2 inches along each edge, then double it over to make it 3/4 inch wide, that makes for sandwiching the plastic with 2 layers above and 1 below for stapling.



Heavy dew:




I sprinkled the staples pretty heavily:


Putting the plastic on in the cool of night keeps from having it sag too much in the heat of day.
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grouch

Not caught up yet. :(


Folding the plastic. It was about this time I realized I could count on the lines on the green paper backing and not have to use a permanent marker to draw a 1-1/2 inch border.


2nd fold:






2 layers of heavy tape where the plastic gets stapled to the center arch:










Conestoga wagon needs wheels.




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grouch

Black plastic. Old vampire rushing to stay ahead of the sun.















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Darrel

It may be a bit unconventional but it will get hot, and you'll soon know how hot.
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

grouch

Quote from: Darrel on June 12, 2017, 03:11:33 PM
It may be a bit unconventional but it will get hot, and you'll soon know how hot.

Yep. It hit 128F by 11 am one morning. That was with the outside layer incomplete; it had and has about 6 - 8 inches open to the outside all along the bottom of each side.

I still haven't loaded it with lumber, though. Stuff keeps eating up time.
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grouch

Oops. Forgot to post the photos of closing the ends ahead of some rain. This was June 5. That was the day it hit 128F and I had to run and rescue my 120F rated remote temperature sensor. Rain rolled in shortly thereafter.












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grouch

After that bout of rain, I spent 2 (partial) days in the hot sun (off and on, between spells of panting in the shade) loading that thing with what lumber I have on hand. Then it turned cool and rained until today.





The sag was just right for unloading.



That load didn't fill it very much.



Thoughtful old Dodge kept rising to make it easy to unload.



2nd load.



Rarin' to go.







Needs about 3 more loads, but I don't have 'em.


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grouch

Somewhere around here, GeneWengert-WoodDoc pointed out that convection alone is never going to move enough air to dry a stack of lumber in a solar kiln. My original intention was to have intake flaps along the floor in that inner wall black plastic, and exhaust flaps at the ridge. The idea was to use a chimney / venturi effect to increase air flow. I don't think that would work simply because the temperature differential between floor and ridge is going to decrease as the whole thing heats up. Serendipity may have come to the rescue.

Those gaps in the outside plastic at about floor level suck in outside air, heat it up on its way up the wall, and blast it into the kiln at the ridge. If I understand correctly, the elevated moisture capacity of the heated air is the key to using it to dry the lumber. Moving that heated air through the lumber stack sucks the moisture from the wood, and then you have to get rid of it without putting it back into the wood.

I'm going to try making the lumber stack the muffler in the exhaust system. I'll drape plastic over the stack like a blanket, with the edge just even with the end of the stack nearest the closed, west end of the arches. The sides will be sort of tucked in. The other end of the plastic will be loosely draped over the foot of the lumber stack, then the edge brought up and stapled to the east end arch. A second sheet of plastic will go over that end, also. This makes the lumber stack the only way for air to exit the kiln. That's where I'll monitor the temperature.

The path then becomes: Ambient temperature air enters through that gap at the base of the outside wall, gets heated between the clear outer wall and black inner wall, passes into the kiln at the ridge, mucks and mills around inside looking for the exit, then gets crowded through the lumber stack to exhaust to the outside at the east end near the floor, if the outer end plastic there isn't closed up to force more heating.

Being a hobbyist and not depending on this lumber to pay the bills, I can experiment like this.
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Kbeitz

Check out E-bay for solar powered camper fans...

Collector and builder of many things.
Love machine shop work
and Wood work shop work
And now a saw mill work

grouch

Quote from: Kbeitz on June 24, 2017, 06:00:22 PM
Check out E-bay for solar powered camper fans...

Thanks, but that's too conventional. :)

All the wind in the world, from gentle breezes to monster hurricanes, comes from just sunlight. I want to avoid converting light to electricity to convert to rotary motion via an electro-mechanical device to make wind.
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Darrel

I've read reply number 45 several times and I'm just not going to read it anymore because every time I read it I become more clueless as to what Grouch has in mind. Then I read reply number 46, sounded good to me. Then when I read reply number 47, the grouch kinda put the kibosh on that.

Now I'm sittin here with this big grin on my face anxiously waiting to see what happens next!

:)
1992 LT40HD

If I don't pick myself up by my own bootstraps, nobody else will.

grouch

Quote from: Darrel on June 27, 2017, 02:29:37 PM
I've read reply number 45 several times and I'm just not going to read it anymore because every time I read it I become more clueless as to what Grouch has in mind. Then I read reply number 46, sounded good to me. Then when I read reply number 47, the grouch kinda put the kibosh on that.

Now I'm sittin here with this big grin on my face anxiously waiting to see what happens next!

:)

Bwahaha! My evil plan is working! Today, Darrel, tomorrow THE WORLD!!1

Let me see if I can make this more confusing. Take a big funnel. Lay it on its side and fill the throat with lumber (properly stickered, of course) such that the ends of the boards are even with the narrow end of the funnel.

Put the whole thing into a jug whose opening is the same size as the big end of the funnel. Cut some narrow slits in the side of the big jug near ground level. Air can get into the jug through those slits, but can only get out by coming out the funnel (backwards to the way a funnel is normally used).

Hang a big sheet over the big end of the funnel so you can control how fast air gets to come out. The heating of the air between jug and funnel throat is what drives air flow.
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