Monday, April 30, 2012

Hypertufa/Papercrete Planter

 The base coat on this planter is plain old hypertufa consisting of (using 2-pound coffee cans for measurement) one can of peat moss, one of Pearlite, ½ of Portland Cement, one of water (there about), and a little lime putty. I’d made the armature using two old, sun-beaten, brittle planters that were ready for the landfill fastened together with sheet metal screws and covered with two layers of poultry wire (see photos below).
So far I’ve found that this type of Hypertufa mix is good for casting but is honestly difficult to daub onto wire without either ready mix joint compound or lime putty to make it stickier. Even then it doesn’t seem very workable. Perhaps more cement to the mix would make it stick to the armature better. I'll continue to research and experiment. As it was, I applied the hypertufa with some force to push it deep into the wire and keep it from falling off.
For the design on front I used the same mixture as above, but substituted cellulose insulation for Pearlite. I guess that makes it papercrete rather than hypertufa. Not only did that make the mix much cheaper, it made it 75% more workable.  The planter had cured overnight, so I could lay it on it’s back to work and wasn’t working on a vertical surface. I added only enough water to make the mix damp instead of wet, mixed in the lime putty, and kept a can of water nearby. I’d take a glob of the damp mix, dip my (gloved) hand in the water, and play with it a bit before applying it to the base coat. This seemed to give me a little more control over how wet the mixture got. I also used a concrete bonding agent, both on the surface of the basecoat and as I worked and modeled the papercrete, sometimes dipping my fingers in the bonding agent rather than the water. Though I still wasn’t able to get a lot of detail, I was fairly pleased with the end result and felt it was a good start. 

Friday, April 20, 2012

Hypertufa/Papercrete "clay" with lime putty

This is a nice, easy to use garden sculpture mix, using “2-pound” coffee cans for measuring and mixing by (rubber gloved) hand in a five gallon bucket.
½ can Portland cement
1 can peat moss
1 can cellulose insulation
1 can water (there abouts…damp (not wet) mix)
Substitute lime putty for ready mix joint compound. Add a big gob of  it and mix well.
Lime putty is builder’s lime mixed with water to a pasty consistency.You will probably need to go to a builder's supply to purchase builder's lime. Neither Lowe's nor Home Depot carry it. This lime putty had set for many months in a sealed five gallon bucket, and was a little “thinner” than ready mix joint compound, and not so sticky. I think that is what made this mixture feel so good. This hyper-tufa “clay” was truly "clay-like" and easy to model over a chicken wire, 1/2 gallon plastic milk jug, and PVC pipe armature. I hope this guy will become part of a scare crow for our steadily growing garden. I have no idea how it will weather.

Monday, April 16, 2012

Baby Turtle

We found this cute little guy while digging in the garden.
What a beauty!
So happy I didn't hurt him as I intruded on his domain with shovel and pickax.
That's a slice of banana in the second photo. You can see how tiny he is.

Friday, April 13, 2012

Sidewalk, Concrete Modeling Clay 2

I finished the little sidewalk leading to the gazebo structure, then created a little bed of mulch next to it to better display the good ol' papercrete hand -- one of my first efforts in papercrete and holding up very well.
Then I set my "faces stepping stones" in mortar on either side of the walkway, and finally, after adding some fence and pieces of rebar, poured the slab.
So far the difficulty with modeling in concrete (sans paper) is moisture.
Very tricky, at best. A hair too much water turns a sand and cement mixture to mush. Then I'm back to adding more sand and cement, trying to firm things up. So far, the best way to mix "concrete modeling clay" is in very small quantities by (rubber gloved) hand. Adding joint compound to the damp, crumbly mix of sand, cement and water makes a soft, sticky "clay" that is still not ideal and makes detail difficult. Even moisture left on the gloves from washing off after mixing will quickly absorb into the mix. I learned to keep a towel on hand for after rinsing. Another turning point came when I left the mixture to cure for awhile -- maybe an hour-- which firmed it up a bit.
All of this is much easier when cellulose fiber (paper insulation) is added, which I didn't want to do for the sidewalk. I'm researching it -- trying to find a better recipe.

Friday, April 6, 2012

Concrete "Modeling Clay", Sidewalk, & Aquaponics

These stepping stones are primarily made of mortar -- one part Portland cement, two parts sand, water to a pasty consistency. The faces are modeled with the same mixture, only with less water -- the mortar was only damp and was clumping a bit -- and a fair amount of ready mix joint compound.
A fair amount meaning...a big gob.
A handful.
I'm hoping these pieces will become part of one section the sidewalk I've been working on. They will be set at either side of a walkway.
This was my first effort at modeling with cement sans cellulose fiber (i.e. papercrete). The "concrete clay" handled pretty well, so I think it's something I can build on regarding my efforts at outdoor sculpture. I have no idea how well this "soft" concrete that is so inundated with joint compound will fare in the elements.
Friday I finally got to work on the sidewalk leading to the gazebo, pouring 12 80-pounds bags of concrete mix.
On the Aquaponics front, we ran the pump five hours on a 12 volt battery -- testing one aspect of a "backup" system in case the power goes out. We probably could have gone longer, but were satisfied that we could run the pump awhile using the battery and a small inverter. We still need a smaller, second pump to use as a spare. We also ordered our Ammonia test strips. Our plants are setting ontop the fish tank in our little Aquaponics house-- two tomatoes, two peppers, a zuchini, and an eggplant --all waiting approximately two weeks for our 12 Tilapia fingerlings from the local supplier.

Sunday, April 1, 2012

Aquaponics 3: Working Out The Bugs

This is an "ebb and flow" aquaponics system, and I originally thought a timer would be the simplest way to go. Most resources recommend 15 minute intervals. The way I understood that, the pump would fill the grow bed to the proper level over 15 minutes (while the bed was simultaneously draining), then the timer would turn it off, and bed would finish draining, and then the timer would turn the pump back on so the bed would fill again. It sounds so simple. The timer I had on hand offered 30 minute intervals. I tried to time things out so that the pump filled the grow bed to an appropriate level while the grow bed drained slowly enough.
There was some trial and error. By the end of the day the Bell Siphon was looking good. In a Bell Siphon system the pump runs continuously. It fills the grow bed to a certain level, at which time the siphon kicks in and drains the bed. The height of the "stand pipe" in the Bell Siphon (generally an inch or two below the level of the grow medium) determines how full the bed gets.
During my initial research, the Bell Siphon had seemed complicated. Maybe I just didn't understand it.
The truth is, you can make a Bell Siphon in about 15 minutes, though perfecting it's operation in your particular aquaponics system may take some time for trial and error testing.
The old bathtubs I'm using as my grow bed and fish tank have 1.5" drains. So I made the first Bell Siphon from 1.5" pipe (so that it fit right into the drain hole of the tub -- that is, a 1.5" piece of PVC for the stand pipe and 3" piece for the bell pipe. That was too big for the little system I'm working with. In the end, I bought an 1.5" to 3/4" PVC adapter for the tub drain and made a 3/4" standpipe and 1.5" bell pipe. This system is perfect. The grow bed fills in...I don't know...about ten minutes (with the pump turned to it's minimum flow), at which time the Bell Siphon kicks in and drains the bed, then stops to allow the bed to refill.
Typically of yours truly, I didn't document building the Bell Siphon, so I have no photos of it's construction. I used this website for instructions. I didn't follow them exactly, but close.
My grow bed is approximately 130 gallons. My standpipe is a 5" piece of 3/4" PVC pipe. My bell pipe is 6.5" 1-1/2" PVC. The four "teeth" I cut at the bottom end ( using a Dremil cutting tool) are about 1" tall. I used a 3/8" piece of clear vinyl tubing as the snorkel tube, and a product called Liquid Tape to seal around it.
My grow medium consists of some large gravel left on our property when we moved here and some "river pebbles" purchased at Lowes. The river pebbles are really too small in that they could clog the Bell Siphon system. To combat that, I made a gravel guard of harware cloth wrapped in nylon window screen.
We're leaving the pump on a few days to make sure we've got it all together enough to buy some fingerlings for the fish tank and plants for the grow bed.