Flash flood takes out my bridge!

Monday afternoon a huge line of thunderstorms tore through Indiana. Lots of wind, a few possible tornados, and massive quantities of rain. In a few hours, several inches of rain added to weeks of previous rainfall. It was too much for my old improvised steel frame bridge. The water spilled over the creek banks and swept up logs and debris. I had relied on this bridge for over ten years to cross this creek to get to my workshop trailer. Now I will be looking to push ahead with my plans to construct a larger bridge. One that a full sized truck can go over. I will keep all of you posted as I progress with it.

Progress at the boilerhouse.

Heres a new photo for all of you. As you can see Its comming along now. I still have alot of work to do on the north and east walls. Then its a door and a window along with finishing the roof.

Firing temps and brickmaking

The finished color and hardness of a clay brick has alot to do with the highest temp achieved and length of time held there before cool down. There doesn't seem to be as much effect on outcome if the ramp up time to peak temperatre is varied shorter or longer. Obviously the type of clay will have a profound influence on the finished product as well. But here I will focus on firing temp of a single type of clay.

Below are tiles and bricks of the exact same source of clay, prepaired the same way before firing.

They are identical except for the one brick on the lower left. The three of the same color were fired to 1900 deg F over an 8 hr period in my electric kiln. The darker brick made at the same time as the others, was fired to 2000 deg F over 9.5 hrs in the same kiln. All settings on the kiln were identical.

The surface of the darker brick is closer to that of a paver or clinker. It has a reflective quality to it that the others do not. All the bricks and tiles are fired fully and have a strong 'ring' when tapped together. The darker brick has a higher ptched ring to it.

If I were to ever try to make pavers or outdoor tile, they would be fired much like the darker brick. I believe the water proof qualities should be higher.

Notice the small paw prints on the one tile. My kittens were having fun after I made up the tiles.

Graphic example of clay shrinkage from firing.

I hadn't ever really gave much thought to clay shrinkage from the firing process. I had read about how it is a normal thing to happen. After making a few more pressed clay bricks for a later firing, I put a finshed brick next to them to compare the colors. What caught my eye though was the size difference of before and after. Pretty amazing when you get a side by side like this.

Bricks in three days

Saturday I came up with a bold idea. To see how quickly I could make a dozen bricks from start to finish. From digging up natural clay all the way to a finshed ready to use good product. It took me two days. Thats it. Three if you want to count cooldown and inspection.

Here are the steps involved and the outcome.

1. Dug up a wheelbarrow load of Flora clay straight out of the ground behind my barn. The clay was already damp from a previous days rainfall. No water will be added.

1:00 pm Saturday

2. Removed all obvious twigs, rocks, and non clay looking dirt material from the load to be formed into bricks. Flora clay at my location is nearly free of roots, rocks or sand. Unusually clean and ready to use for this area of Indiana farmland.

2:00 pm

3. Load brick press and press out 12 bricks. Used all three of my frog logos just for the heck of it.

3:30 pm

4. Load into the electric kiln to begin the drying out. This is really tricky. Too fast and they crack. Too slow and the wont dry for a month!

4:00pm to 9:00pm Saturday.

5. Fire in the electric kiln to at least 2000'F.

7:30am to 9:00pm Sunday

6. Cooldown , unload and inspection.

4:00pm Monday

Success!!!!

Test run of my first water wheel.

I placed the water wheel I built into the streambed to test it out. Work out very well with only a little head pressure to turn it. I will need to make a proper raceway for it to achieve usefull power. But its fun to watch it turn endlessly.

Here is a short video of it in motion. Quality is poor, from my cell phone. I will get better vids soon.

My electric kiln works great!

I have used my electric kiln today for the first time. Everything went smoothly. About 8 hrs to make 2000'F. The clays have much more reds to them, save the one creek clay brick I fired. That one may need to go to a higher temp. My first experience with electric kilns. This one has a humm or buzz sound when the elements are being electrified. Guess thats normal. Pulls about 12 amps when one coil is on, 24 amps when they both are up and running at 240v AC.

Whats easy about this, comming from wood firing, no wood stoking!!!! Dont get me wrong, I like the connection with the earth and wood firing. But sometimes its nice to just plug it in and let it buzz for 8 hrs with less effort. Lets see how good I feel when I get my electric bill! lol

I am next gonna fire a bunch of clay tiles for a house project. I will let you know how it goes.

Green energy from my creek.

One of my many 'other' projects is this water wheel ive been building. My plan is to put it into a water chute I will build in my creek along with a dam. If I can get this to work reasonably well, it should have enough power to spin a small generator. Depends on several things how well it will function for me.
If I can build enough head pressure at my dam to move the water down the chute forcefully.
What kind of speed will the wheel turn at and with how much torque?
Will it do as well once under load from a generator under load as well?

Specifics:

36" dia wheel

28" wide

1.5" output shaft dia.

More clay tiles fired. Keeping away from reduction in wood firing.

I fired some more homemade clay tiles a few weeks ago in my wood kiln. Just hadn't gotten around to posting anything about it till this morning. Pretty uneventfull firing and results were ok.

As you can see the colors vary depending on where they were in the kiln and the paths the flames took. I was hoping for a bit more reds from the clay in the tiles. No salt glazing here. Looking more for a dark terra cotta red. The attempt was to keep away from strong reduction so as not to darken them and pull to much oxygen out of the iron oxides. It kinda worked, but I think it will require a trade in order to get more deep reds. By keeping reduction in the kiln down I also cripple some of my peak temperature by stoking less fuel. So in order to get enough 'heat work' done to the clay I must lengthen the firing time in the neutral and oxidizing enviroment I create inside the kiln.

You can compare the tiles to 'real' red brick directly behind them.

Got myself an electric kiln!

Hey I found a great deal on an old Duncan electric kiln off of craigslist. So now I have this to play with too. Yippie!!!!!

Making some more clay tiles.

Im still always on the lookout for common objects that can be used to make cool patterns on my tiles.

This old water valve handle was a throw away item now reborn as a clay tile stamp.

Compressed earth bricks, back to the drawing board.

Its been almost a year since I constructed the chimney of the aluminum furnace out of CEBs. Indiana has a harsh winter season with more than a few freeze/thaw cycles. This is the result of exposure to that bitter winter moisture!

Spalling of many of the faces of the bricks due to freezing after moisture intrusion.

Notice how the mortar has held up better than the clay body of the bricks.

My initial hypothesis is that I skimped too much on the cement content of the clay mix for the bricks. The higher level of cement would likely add to the moisture resistance of the bricks by lowering their water absobtion rate. That is critical in outdoor enviroments where water and freezing are combined threats.

Not sure what I will do about this yet. I do know that any unfired CEBs that I make in the future will have a higher cement quantity in the clay mix. Or I may skip the cement and just fire my CEBs in a clamp kiln to vitrify them and gain the waterproofing needed for my Indiana climate.

The aluminum furnace chimney may be torn down and rebuilt, not sure yet about that either.

Playing around with low fire glaze.

I bought some used glazes off of Ebay awhile back and have been trying them out to see how they effect my clays. Some glazes turn out very clear, while others add some interesting colors to the result. All of them are in the low fire range at cone 04 to 05 by the instructions on the bottles.

This platter has a nice glossy wet look.

This rough bowl ended up blue with some reds in spots. I am gonna play some more with this one.

This is a combo glaze job on the candlestick holder. Blue down the flutes and throat with a bit of red on the raised parts.

This one has some redish spots on it that the photo dosn't give justice too.

Dont know why the picture flipped like this. The little square bottle is something new im trying.

New stuff for the kiln.

My new pyrometer thermocouples came in yesterday! Thanks once again for Ebay. Ive been fighting using crappy old thermocouples and even went as far as making my own. Funny think was I learned alot about how they are made and work. Having these should make my kiln temp monitoring a bit easier now.

8mm type K thermocouples

Ive also made up some new clay mix. Just waiting for warmer temperatures and motivation to make some new pottery. I have some new ideas I want to try. Thinking about small clay bottles.

4 parts field clay, 1 part glass dust

Fire and snow.

Heavy snowfall tuesday. Spent the day on another 6.5 hour quickfire of the kiln. Salt glazed the last hour and half. Very good day watching the snow fall while gathering firewood and stoking the kiln.

I am very excited about the heat this firebox can generate in the small chamber.

I actually have to hold back on stoking speed sometimes. Thats still a new one for me.

And it can make alot of really black smoke if I put to much in to fast.

When I start in the morning, I use a kerosene heater in the barn for warmth. But after about an hour, the heat off the kiln becomes plenty in itself. So I turn off the heater for the rest of the day.

There were two pots on the left from the last firing that I refired to get a better glaze effect. I put in a few tiles too. They came out nice.

I liked this pot and plate.