AusBonsai

Hi
I have been having a go at making my own pots. I have used raku clay and terracotta to make slab built pots but I was wondering if anyone has found a similar clay to the stuff that the older japanese pots were made in. Aussie Terracotta is orange and i would like to make the dark brown terracotta in my unglazed pots. I would appreciate any advice anyone could offer.
DMS

Offhand, I know Keane's stoneware 9 is a similar colour. You will need to fire it to stoneware temperatures, of course. Have a look at the clay samples in the catalogues of different clay companies. you should find something you are looking for.
Penny.

Hi Dms

If you want to stick with terracotta, you can add oxide to the clay & work it well thru to darken the colour. You may have to do a few test batches to get the colour you want.

I have also recently started making pots but am working with stoneware clays. Theres quite a good range of colours available including a dark chocolate & red brown, as well as several types which have included grog which compliments many natives as well as traditional bonsai that have a rugged bark or style to them..

Have a look at http://www.walkerceramics.com.au/ for a good range, including images of fired samples at various temperatures.

Look forward to seeing some of your pots.

Matt

Hi matt
Thank you for your reply, So are bonsai pots stoneware? not terra cotta?
DMS

It is not a good idea to start adding reactive materials to a clay body. Commercial clays are formulated to perform well under specific conditions and when you start adding to them, a lot of unexpected things can happen - a lot of them not good. As well as this, some oxides are poisonous eg. Manganese Dioxide which will give symptoms like Hodgkin's Disease and is fatal.
Bonsai pots can be made from terracotta and other low-fired clays, middle-fire clays approx.1160 - 1200 deg) or stoneware. They can be slip-cast, thrown or hand-built.

DMS wrote:Hi matt
Thank you for your reply, So are bonsai pots stoneware? not terra cotta?
DMS

As Penny has said, you can make pots from across the range of clays that are available.

Our opinions differ when it comes to the use of additives within a clay body. I have a number of pieces fired over 2 seperate tests that had various additives. Some of the results were not as expected, others were truly beautiful (to my eye).

I think most older chinese and japanese pots are usually earthenware. Over time the water absorbtion of earthenware & low fired clays will change the colour of the pots especially with paler bodies. Stoneware has a fair amount of frost & water resistance when fully fired.

Matt

Heres a good link on pots
http://www.peter-krebs.de/

If you are looking for a smooth clay that will give you a nice brown colour my answer is Bennets terracotta. I would have to look up the exact order number. It is a terracotta that can be fired high. I have fired it to 1280 (gives a beautiful chocolate brown), but it had some dunting, I have now fired it to 12oo. At 1200 it is a medium brown, not quite as nice as at the higher temperature, but still a nice colour. In the next week or two I am going to try firing to about 1220 and see what that will give.
My favorite clay is BRT (Feeneys) if you don't like the black spots you could try Buff raku with sand.
Lynette

Gday DMS, I'd love to see some of the pots you have made.. Are you part of Geelong Club?

Adam

Hi Adam,
I am a former member of Geelong, but I have found it difficult to get to meetings so I am happy to do my own thing. I will post some pictures of my pots soon.
Cheers DMS

Re

Bennets Terracotta, I have been experimenting with this clay. Have fired it to c6-7 in reduction and is a nice dark brown and is vitrified. I weighed it, soaked in water and re weighed. very little gain. Would like it to be a little smoother though. Have just finished a large rect pot,16kg clay Waiting for it to dry.
Hope this helps

16 Kg....WOW !!

I'd love to see it.

Cheers, Pat

So would I.
Penny.

The filtered terracotta is smooth, perhaps you used the unfiltered, because it is so much cheaper. I have only used the terracotta, but am going to try some of their stoneware as soon as I get my next order.
Lynette