Major Burn…

I’ve wanted to get a new burner for our little propane kiln, because one of ours doesn’t work properly.  It puts out a reduced flame, meaning a very sluggish flame that puts out more smoke than heat.  So the other day I was going to order some fire blanket and a pair of raku tongs for a project Keturah thought of.  So I thought I would go ahead and buy a burner at the same time, figuring it would help the kiln fire faster and more evenly.  So I picked up a small venturi burner designed for burning liquid propane.  When I finally got the package, here’s a picture of what we received:

 

I wanted to test out the new burner so I put what I had in the kiln and started a bisque firing.  I started by placing a small propane torch on a five foot cord in the kiln and turned it on low for about an hour to preheat the work.  Then I add one of the venturi burners on low and remove the small torch, I leave it this way for a half hour and then I usually add the second burner.  When I went to add the second (new) burner it was doing the same thing the old burner was, a slow, reduced flame, after much nashing of teeth I started to think of what the problem could be.  I figured that there might be a clog in the line reducing the flow of gas, so I went to buy a new hose.  If it wasn’t the hose my next guess would have been the pressure regulator, but when I hooked up the new hose and lit the burner it burst to life with a satisfying growl.  So now I believe I have three working venturi burners, I still need to test the old burner, but I think that it will work just fine now that the hose has been replaced.  Once I added the second burner to the kiln it finished in record time.  It usually takes about 6 hours to fire this little kiln to bisque temperature (1850f/1010c) which is a respectable time and one I’m used to with electric kilns.  But this time with both burners working properly it only took about four hours!  So that’s pretty cool, I’m really excited to have a properly working kiln, now to make some new work to  put into it…

A Working Body

Last month I was finishing a body of work that I had been thinking about for a couple of months.  I’ve been trying to think of a way to make work with the limitations of not being able to glaze my work, our current kilns are not trustworthy enough to do anything but glaze in.  In my last body of work I used markers to touch up and add to the scenes on the pots, I really like how this looks and had wanted to use it again.  So with this new work (and not being able to glaze anything) I decided to go full out and use marker to decorate all the vessels in this series.  I expanded a little bit to include different colored India inks, these I used mostly for the banding lines and for larger areas that needed to be filled.  I made this new work out of a commercial clay body called B-Mix (cone 10), it is a mixture of porcelain and a white stoneware.  This gave me a smooth white surface for the stories I wanted to convey, it also allowed the markers and inks to “pop” off of the surface of the vessels. 

                The actual content of this body started with doodles I used to do when I was in primary school.  I would draw a cave or dungeon type scene with traps and treasures hidden within them.  I would then draw a little stick adventure man to climb, swing, and jump his way through the drawing discovering all the hidden things I had placed.  I had shown Keturah (my wife) how I would draw these when I was a kid and she loved them, she thought they were the funniest thing she had ever seen, and said that it would be a good transition from my last body of work to a new one if I could put them on to some pots.  So I sat down and sketched out some ideas in my (hand-i-dandy) sketch book of what kind of stories I wanted to convey, and then I moved into the studio and threw some forms that I thought would look good if seen from a distant.  I then bisque fired them in our converted gas kilns, and then after some hesitation (I always get nervous before committing pen to paper or in this case pen to vessel) I started drawing onto the forms I had made.  Here are some of the finished pieces:

The drawings evolved from the adventure man traversing caves to Greek style stick figure pieces.  I have always been a huge fan of Greek pottery; I really enjoy the variety of shapes and the wide range of subject matter they portray.  So I made some Greek inspired vessels and gave them some Greek styled stick figure scenes.  Here are a few pictures:

I really enjoy using humor in my work, and the idea of bait and switch.  By that I mean I enjoy giving the viewer something beautiful to look at from afar, while putting enough detail in the scenes to draw the viewer closer to the work.  At which point they realize that that beautiful vessel is decorated with stick figures and scenes from a child’s over active imagination.

An Enso Crown Affair

Here is a picture of the crown that Keturah was working on.  It has since been fired, and will soon be on its way to a new home.

 

 In other news, we were not able to get all that work glazed and fired so no new pictures of finished work.  They messed up my schedule at work and my weekend was taken away.  But in better news I now have a weekend off and will be glazing and firing the kiln this coming weekend.  So be looking for new work on our Etsy site starting next week, and some posts of how the firing went and pictures of the finished work.

A Kiln is Born (well reborn really)

So today I started work on converting my electric kiln into a gas kiln. It went pretty well if I do say so myself. I haven’t had a chance to fire it yet but I’m very optimistic about it reaching at least a bisque temperature (which is about 1850F/1010C or 1283.15 Kelvin). I started this project by cutting a way a circle of the thin metal that surrounds the kiln near the bottom. I was hoping to be near the floor of the kiln without cutting into the actual bottom. I was not successful in avoiding the floor, but I realized this before I cut into the floor. So I had to move my hole up about two inches which was fine, although now it looks a little goofy. I used a hammer and chisel to cut through the metal and the soft brick, I was originally going to use a drill but I didn’t have one big enough and the smaller one I did have was having trouble getting through the metal. Here is a picture of the resulting hole for the burner.



After running amuck on the burner port I moved onto the flue. Which in this case is a hole roughly the same size as the burner port. This hole was also created using the hammer and chisel method, although it turned out better because I didn’t have to worry about cutting into anything that I wasn’t supposed to. I beveled the edges (inside and out) to give the flue a more finished look, I didn’t want it looking unfinished you know.



I will be using a kiln shelf to open and close the flue to help regulate the temperature inside the kiln. Also this will help when I attempt my first high fire reduction, which I have never done with an updraft kiln (which is what this type of kiln is now, basically the heat/exhaust goes from the bottom through the kiln and out the top).



Here is a picture of the kiln with the lid up, so you can see both the flue (at the top) and the burner port (at the bottom).



I have two venturi burners that I acquired through my journeys as a graduate student. I plan on using one of them for this kiln, I believe it is small enough that one will be enough, but if I need it I have the other one waiting in the bullpen. I did need to find some pieces so that I could connect the burner to a propane tank (I’m using a small tank similar to the one used for barbeques).



This is the first piece it’s a 90 degree 3/8 flared nipple, I wanted a straight one but lowes didn’t have any and that’s where I work so I didn’t go anywhere else.



The next piece I needed was the regulator that attaches to a barbeque propane tank.



This was attached to the burner via the nipple, and here is the finished burner all assembled and working. I fired it up just to make sure it works, and managed to burn some of the hair off of my forearm in the process.



I’m hoping that it rains here for the next few days because I know we need the rain. But at the same time I’m hoping it doesn’t because I would really like to see if this setup works. I was going to fire it today but I might as well have it filled and ready for a bisque load when I do, so I don’t waste the fuel. I wish I would have had the fore thought to make some cone packs before today, but I didn’t so now they are drying out so they don’t explode in the kiln. The cone packs are used to determine the temperature in the kiln. Each cone is design to melt at a specific temperature. I use four of them so that I have an idea of how much longer the kiln will need before it’s finished.