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Culture-historical workshop at Knudsgaard Oleflemming – firing black clay pots. Firing your own pots. In Jutland were black pots originally fired with heather peat. You placed more and more at the fire - until you were able to see the pots glow.
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Culture-historical workshop at Knudsgaard Oleflemming – firing black clay pots
Firing your own pots • In Jutland were black pots originally fired with heather peat. • You placed more and more at the fire - until you were able to see the pots glow. • In order to obtain the black color (reducing combustion) in the end all were covered with sand and ash from previous firings.
Firing your own pots • Potty wives found out that an iron pot that totally covered the black pots ensured a consistent result. • Use such big iron pot and it's really black pots you get. • Firing pot this way is however a tough way to fire! • The burning process takes approx. 6-7 hours hours! • Any kind of sloppiness punished!
Firing your own pots • Why do the pots turn into black? • The clay contains from natural iron oxide (rust) and is in a regular ceramic oven they will be red. • Under the big iron pot the pots are wrapped in straw, which by the 8-900 degrees consum all the oxygen. • The last oxygen is coming from the red iron oxide, which then turn into black iron oxide.
Firing your own pots • It is essential that the pots are allowed to dry slowly. • 2 weeks is not too much! • Loosely covered with plastic.
Firing your own pots • The pots are now dry enough. • Check by putting your cheek to the pot. • Is it cold, let it dry a little longer!
Firing your own pots • The pots are preheated to 150-200 degrees. • In the old days the open chimney was used, here the pots stood on some planks for some days. • Or they had a “firehouse”. (see photo)
Firing your own pots • Now it's easy with an electric ceramic kiln or the oven in the kitchen. • The heating to 150-200 degrees must go slowly 2 - 3 hours. • Before it took 2 - 3 days!
Firing your own pots • You will need: • 1-2 old big iron pots • 1 wheelbarrow • 1 pair of blacksmithsgloves • 1-2 bales of straw • 1m3 dry wood • 1 wax taper • 1 broom • 1 long rake
Firing your own pots • Wax taper “Fidibus” = iron fence post on which a cloth is secured with wire. • With a little diesel fuel added it is a nice little torch to light the fire with.
Firing your own pots • 4 – 5 large wheelbarrow full of wood. (spruce - pine - larch, and the like) • It depends on the calorific value. • Hardwood - a little less volume, but everything can in theory be used.
Firing your own pots • You can do this with smaller amounts of the different stuff. • You just have to find a smaller castings pot at a garage sale.
Firing your own pots • You will also need: • Plenty of space. (At least 5 m free to all sides of your fireplace.) • Fine weather = (dry and calm - wind under 4 m / s) • It is best to start in the evening, when the wind usually settles a bit.
Firing your own pots • Do not take chances with the weather! Use the local weather forecast • Do not start the firing, if there is a risk of rain / thunderstorms. • The gusts before such would give so an imbalanced heating, that the pots burst.
Firing your own pots • The big iron pot is put into the wheelbarrow supported by straw. • Then start by putting straw in the bottom of the pot. • At least 5 cm thick layer formed as a nest.
Firing your own pots • The clay pots should be wrapped securely in straw - both outside and inside. • Do not let them touch the iron pot inside!
Firing your own pots • The wood and straw are ready. • The cast iron pot is placed with the opening down. • There is covered with a 5-10 cm wide buffer strip sand and ash along the rim of the big pot. • This is important to get it airtight.
Firing your own pots • The wood is placed around the ironpot • The thickest pieces inside. • Place short pieces at the top.
Firing your own pots • The layer of wood around the iron pot must be at least 40-50 cm thick. • Over the pot smaller pieces of wood in an equally thick layer.
Firing your own pots • Place straw around the entire stake. • It is important that the fire catches from all sides at the same time. • Help possibly with diesel fuel. • The even heating is EVERYTHING.
Firing your own pots • In order to have fire all around you using your wax taper. • Wetted with diesel • You must be as swift as possible, ignite the straw with 30 centimeters intervals.
Firing your own pots • Use sand to put it out again.
Firing your own pots • The flames turn now high. • Look carefully to see all sides burns alike.
Firing your own pots • WARNING • Starting the firing using diesel fuel is dangerous – use as little as possible. • And keep children and animals in safe distance!!
Firing your own pots • To think of: • When the fire really flames, it emits a very strong radiant heat. • It's a very good idea to have water nearby! • But don’t hit the ironpot with cold water, it’ll break.
Firing your own pots • The iron pot is exposed and are not glowing. • Do you see this - within the first 45 minutes - more wood should be added on the spot. • It's a always a good idea to have some extra wood lying nearby.
Firing your own pots • Use a rake or other to get the pieces of wood put right where they should be. • Walk side wards when you approach the fire, then you feel the heat less.
Firing your own pots • The first time you see the iron kettle exposed, it should glow cherry red! • The temperature is then from 800 to 900 degrees.
Firing your own pots • After a time the iron pots are again to be seen. • One must still be wary of getting the cooling regularly. • With the batten / rake can push around with the wood.
Firing your own pots • The flames die out, and there are only embers. • It takes approx. 3 hours. • So you just have to wait 3-4 hours more before everything cools down. • You should be able to keep your hand on the iron pot (50 degrees) before removing it. • Open to see the nice black pots too soon might ruin them!
Firing your own pots • Dew or a small rain shower make no harm. • You can just wait until the next morning. • However if your impatience is too big, you can also wait up (Until 2 a.m.or 3 a.m.)...... • It just needs to be cooled so much, that you can tuch the big ironpot!!
Firing your own pots • Then it's time to see the result.
Firing your own pots • Are they now completely black? • If they are not, you've saved too much on the wood! • They can be fired once more, but you MUST get temperature higher up the 2nd time.
Firing your own pots • We polish the pots after firing with a paste of beeswax • Should they not be used for food, one can simply dissolve the wax with turpentine.
Firing your own pots • A more "green" paste can be obtained by melting the bee wax in cooking oil in a water bath. • Mix 1 part wax with 6-7 parts of cooking oil. • Warm up slowly and cool, stirring constantly. • If the paste is gritty cooling happened too fast. Start all over again! • The consistency should be like gruel. • Is it too thick, it can be primed up a bit with cooking oil.
Firing your own pots • The wax solution is applied with a soft brush. • Then polish with a stiff brush. • Eventually the "refined" with a cloth. Do you store the pots in a cold place, the wax may crystallize, and the pot will be gray and dull to look at. • It is then necessary to polish them again.
Firing your own pots • Here you can see the difference on the front pot. • Patterns and glossy surfaces more clearly after beeing polished.
Firing your own pots • Many prefer not to polish their pots. • Pots not polished, clearly shows how the straws have left their marks. • Personally, I prefer unpolished pots.
Firing your own pots • Should you encounter problems, or have unanswered questions, please feel free to contact me. • Mail: oleflemming@yahoo.dk • Skype Name: oleflemming1 • Facebook Ole Flemming Nielsen • Please tell me, should you desire other presentations.
Firing your own pots • Would you like visit Knudsgaard? • The address is: Tim Kirkevej 30, 6980 Tim, Denmark (15 km north of Ringkøbing) • To be sure I’m at home mail me rather in advance. • oleflemming@yahoo.dk • More information to be found on my site: http://www.jydepotter.dk
Firing your own pots • This is a description of how I do, but .... • I do not know the local fire statutes, where you live. • You are solely responsible for everything going legally.