May 31 2013

Accreditation Program for Hadar’s Clay™ Teachers – Group of Summer 2014

Applications are now being accepted via email for the second group of Hadar’s Clay™ accredited teachers, which is about to begin its activity in August 2013.

The goal of this program is to establish a team of high-level, professional teachers, who know the ins and outs of base metal clay and who received their training directly from me. They will not be authorized to accredit other teachers. Hopefully, they will form a non-competitive, supporting group that will stay active after the program is over.

Once trained and accredited, Accredited Hadar’s Clay™ Teachers will be listed on the Hadar’s Clay Accredited Teachers’ Registry on my website, along with their contact information and links to their websites. Accredited teachers will receive my ongoing support.

One part of the program is a 5-day hands-on workshop. However, the activity of each group starts online several months before the class, in the form of questions and assignments.

Each round of accreditation will have its own dedicated Facebook group. The first round of accreditation started in March 2013 and will end in January 2014. The second round will start in August 2013 and end in summer 2014.

How do people get into the Accredited Hadar’s Clay Teachers program?

Please contact me via email if you wish to join the second round of accreditation. The requirements are:

1. Having taken a workshop or with me. Workshop or classes taken during the training period (except for the final 5-day workshop) also count. Please follow my travel-teaching schedule.

2. Familiarity with my books, the Instruction Manual for Hadar’s Clay, and related files published on my blog.

3. Experience with Hadar’s Clay.

4. Experience with the firing and finishing process.

5. Willingness to dedicate the time and effort required to complete the program.

Please email me your information with photos of your work with Hadar’s Clay. If your application is approved, you will receive an invitation to join a Facebook Group.

May 27 2013

Drying Low-Shrinkage Steel XT

Low-Shrinkage Steel XT does most of its shrinking while it is drying, not so much during the firing process. This shrinkage can cause the steel to distort significantly while it’s drying. How do we prevent it? People have come up with all kinds of potential solutions, including air-drying, or drying under heavy objects. However, because of friction between the back of the piece and the drying surface, the flat piece may crack while trying to shrink (even if you oil the surface). This can happen even if you dry it very slowly or in the air. Placing a heavy object on top of it is likely to interfere with the shrinkage and cause cracking.

The best way to dry a flat square is to watch it and flip it over once it starts curving upwards. Then flip it again when it starts curving again. By flipping it each time it curves, you allow it to curve back in the opposite direction until it is flat, while also avoiding friction with the drying surface. The process is short and safe.

Here is a short video clip demonstrating the process:

May 15 2013

Instruction Manual and Pre-firing

The Instruction Manual for Hadar’s clay is now updated and marked May 15, 2013.

Besides adding instructions for firing Smart Bronze, changes have been introduced throughout the Instruction Manual. I recommend reading it through when you get a chance, since it may shed some light on your personal experience.

I would like to share with you my experimentation with pre-firing.

First, not all clays require pre-firing. White Bronze, Smart Bronze (up to a certain thickness) and Low-shrinkage Steel XT do not require pre-firing. Steel, decorated with copper and/or Bronze XT, also does not require pre-firing.


White Bronze

Smart Bronze with Aquamarine

Smart Bronze


Low-Shrinkage Steel XT

LS Steel XT + copper/Bronze XT Overlays

Low-Shrinkage Steel XT with overlays of copper and Bronze XT

Copper and the rest of the bronzes do require pre-firing. Firing longer hours and/or ramping slower has never worked for me. Recently I have done some more experiments with pre-firing in the kiln instead of on the stove-top. Here is what I did:

Brick top-loader kiln

I placed a bowl inside the kiln with copper and bronze pieces resting on top of carbon. Set the kiln to mid-fire schedule.

In the kiln

In the kiln, set to mid-fire schedule

As the kiln reached 500°F I opened the lid to check on the pieces. I kept checking every 100°F. At 800°F pieces started to smoke and turn black.



Getting black

Getting black

At 1000°F the smoke was gone and the pieces were all black. I carefully turned the pieces over with a spoon to see if they are black on the other side.

Turning over

Turning over with a spoon

The other side still not black

The other side still not black

This one too

This one too

They were not, but they turned black within seconds. I covered them with carbon, closed the door, and let the kiln complete its cycle. Worked great. 2:45 minutes from beginning to end. If the pre-firing is done on a stove-top, this is the time it takes for the second phase alone. So firing this way is shorter and easier than on a stove top.

Covering with carbon

Covering with carbon

If you happen to walk away while the kiln is ramping and come back after it reached 100°F, no problem. Pieces are probably all smoked up and ready for more carbon. Oxidation will not happen if it’s under 1:00 hour, and even if it does, it will be reversed while the pieces are fired inside carbon.

Turning the pieces over is a good idea. Also, it doesn’t matter if the vent hole is open or closed.

Muffle, front-loader kiln

I tried the same thing in a muffle kiln. Surprisingly, the pieces did not show a sign of smoke until the kiln reached 1200°F. At this point the carbon was already on fire. Since it was a front loader, I had to take the bowl out of the kiln to cover the pieces with carbon, which was awkward at this high temperature. And after the second phase, the pieces were not sintered.

I am guessing the reason is the fast ramp of this type of kiln. The chamber got hot, the outside of the pieces got warm, but the inside needed more time. So slowing the ramp may be the answer.

But then I found out something else. I know that firing twice always works, so I tried it again, but with less time. I fired the pieces in carbon at 1510°F for 1:00 hour. It took 1:20 minutes. Took the bowl out of the kiln and cooled the bowl and the kiln under 100°F. Put it back for another hour, and it worked. Another 1:20 hours, plus cooling time. A little longer, but less messy and more successful.

In fact, the easiest way for me to fire in a front loader was to fire 1:00 hour before I went to sleep. In the morning the kiln was cold so it wasn’t necessary to take the bowl out. Didn’t even open the kiln. Just fired one more hour.

May 5 2013

Free Project for Smart Bronze – Solid Ring

New media seem to bring new inspiration. I’ve always leaned toward hollow forms. It never occurred to me that I could work with solid forms, mainly because I was put off by their weight. As it turns out, Smart Bronze is very lightweight after it’s been fired (although not as light as Low-Shrinkage Steel XT), so I decided to give it a try. Once I started, the possibilities seem endless.

Here are instructions for making this ring.

Garnet and Sapphire

The ring weighs 11 grams after firing. The instructions are long, but only because they are very detailed. It’s actually pretty simple.

1. From the ring sizer, pick a ring that is 2½ sizes bigger than your desired size. Trace the inner diameter of the ring with a pencil. (Tip: if you don’t want to separate the ring from the sizer, do it on a corner of a table; this is the only way it’s going to lay flat).

Trace inner diameter

2. Find a tube whose outer diameter is the same as that of your traced circle.

Find a tube

Or: Find a circle template with the same diameter.

Find a circle template

3. Here is the template for the ring:

4. Roll a large layer of Smart Bronze 3 craft sticks thick (18 cards). Cut a circle in it using the tube or the template.
Cut a cricle

Cut a circle

5. Remove the circle. Place the template on top of the layer.

Template on layer

6. To cut the shape of the ring, it’s better to use cutters rather than a knife. Using cutters will help ensure that the cross sections are vertical. Pick a circle or oval cutter that fits the curve on the top right of the ring. Cut this section out.

Cut section out

Cut section out

7. Use a tissue blade to cut the next straight line.

Cut line with tissue blade

8. Use circle cutters to cut away the excess from the layer on the right and left side of the template.

Remove excess with circle cutters

Remove excess with circle cutters

9. Remove the template. If you used a tube to cut the shank, put it back in the hole. This will help prevent the circle from distorting while drying.

Return tube to hole

10. Dry the ring thoroughly, then sand it smooth.

Sand it smooth

11. While the ring is drying, set the stones. You can use any fireable stones. I used an oval natural sapphire and a square natural garnet. For the oval stone, press the stone into a thick patty of clay. Squeeze a drinking straw into an oval shape and cut an oval around the stone. Dry, then sand the bezel to the perfect oval shape.

Set the stones

12. Set the square stone the same way, only use the scraper to cut the bezel around it.

Setting the square stone

13. Attach the bezels to the ring with thick paste. Dry.

Attach bezels to ring

14. Place the ring in carbon, on top of thin fiber paper. Place a piece of fiber paper on top of the shank as well. Cover with carbon, and fire.

Brick kiln: ramp at 1400°F/778°C per hour to 1440°F/782°C. Hold 2 hours.
Muffle kiln: Ramp at 1400°F/778°C per hour to 1490°F/810°C. Hold 2 hours. Make sure the overall ramp time is at least 1:00 hour!

15. After firing, finish the ring following the instructions in the document entitled “Finishing Fired Metal Clay,” available on the right-hand panel of this blog. You can polish it to mirror shine.

Finished ring

Finished ring

Finished ring