Continue working with clay at home... How to choose what materials to buy?
For those of you would like to continue working with clay at home during the lock down, and would like to know what options are available, this blog will give you some ideas of how to choose the right materials to buy.
First decision you need to make is, do you want your pots fired? If you attended any of my workshops or courses, you would know that we use Stoneware clay in the studio which requires two firings (bisque firing and glaze firing). There are clay out there does not require firing, and they are generally known as air-dry clay. There are limitations of using air-dry clay, such as not food safe, and remaining fragile etc, but it allows you to have a go making nonfunctional pieces, and also allows you to decorate it with acrylic colour, which is wildly available and doesn't cost a fortune.
Once you have decided if you want to use proper clay or air-dry clay, you can then move onto the next step: getting hold of some clay. There are many suppliers that sell air-dry clay, you can even order some from Amazon. Since I have no experience working with air-dry clay, I recommend you to do some research and maybe try a few brands to find the one you prefer to work with. If you prefer to work with proper clay, there are a few more things to look into before buying any.
To work with clay that requires firing, you need to find somewhere to fire your work eventually. Look for pottery studios near you that offer firing service. Most private studios are happy to fire your work for a fee, even if it is not advertised, you should always email to ask. Council run studios may also offer firing service, and you may need to speak to the correct person, for example, the kiln technician, to find out more information. Clay Craft magazine has a pottery courses listing which may help finding a studio near you: https://www.claycraft.co.uk/pottery-courses/
Once you find a studio that can fire you work, the next step is to find out what temperature that studio fires to. Clay can be divided into two groups by the firing temperature: Stoneware and Earthenware. Usually Earthenware clay can be fired up to 1180°C, and Stoneware clay usually requires to be fired to at least 1200°C in glaze firing, till up to 1260°C or even higher for some specialise clay bodies. The clay body determines the range of decoration materials you should use too. You can ask for recommendations for clay body and decoration materials from the studio that will fire your work before you look into buying any of them.
Moving onto decoration materials, it gets more complicated because there are more options and more methods to apply them, and more knowledge required to fire them correctly. You need to match the decoration materials to the correct firing range: earthenware or stoneware. A lot of things can go wrong with glaze firing. It is quite comment that studio technician may hesitate firing work that are glazed with a brand or a range of glazes they are not familiar with. I wouldn't recommend raw glazing either (applying glazes on a piece of work before it was bisque fired), and I will not fire raw glazed work in my kiln in general. When things go wrong, it could be as little as ruining that single piece, to ruining the whole kiln of other work, and to the worst extend, damage the kiln permanently. It is simply a risk to much to take for me. My recommendation is to stick to underglaze. Underglaze is a bit like pottery version of acrylic paint, which contains colour pigment that can withheld high firing temperature and brush on medium that stick to your pots. Unlike glazes that show movement in glaze firing, underglaze pretty much stay where they are. The colours are usually straight forward too, what you see is very close to what you get, which enable you to create new colours by mixing a few colours together. The application is also simple, you can use a brush to paint details or abstract, just like how you would use acrylic paint. The name underglaze also suggests that it's a material to put under the glazes. You can use it either at greenware stage (or even bone dry stage if you clay body allows), and at bisque-ware stage. You just need a layer of transparent glaze on top to make it food safe. This will may it easier and a lot less risk for the studio technician to fire and glaze your pots.
To give you an example, if you would bring your work to my studio to fire, below is my recommendation:
Make your work less than 30cm in diameter and under 65cm in height, otherwise it won't fit into the kiln. The firing fee is charged by shelf and usually at £25 per shelf per firing. Each shelf is 38cm wide times 20cm height (you shouldn't make a single piece of work wider than 30cm, otherwise it leaves no space for props), and can fit as many pieces as the space allows.
Use a stoneware clay body that can be fired to 1240°C as that's the top temperature we fire in our kiln. (The exact clay body we use in the studio is KGM body from Valentine's Clay: https://www.valentineclays.co.uk/product/kgm-body ) You can collect and pay for a bag from our studio once lock down has lift, or order home delivery directly from the manufacturer. Please note I do not fire paper clay due to the smoke that comes out from the kiln when the paper fiber is burning away
Use underglaze to decorate your pot. The exact brand of underglaze we use in the studio is Contem Underglaze, but I don't think it matter much from brands to brands, any underglazes that can fire to 1240°C will be good. If you already decorated your pots with underglaze when you bring them in for firing, I most likely will offer to glaze your pots in transparent to save you a return trip to collect the bisque ware, glaze it at home, then bring it back. It also speed up the firing as we can load your pieces in the next available firing instead of having to wait for you to bring them back glazed.
If you are using glazes to decorate your pots (after they were bisque fired), I recommend using brush on glazes, and leave at least 1cm from the base and the base unglazed. Glazes you used must be able to fire to 1240°C (Cone 7), and NOT all stoneware glazes are recommended to fire to this temperature, make sure you check the product description. If any glazes run down to damage kiln shelf, you maybe liable for the fee for a replacement shelf.
Finally, we are ready for some shopping!! Below are some suppliers I use regularly:
Clay Cellar: https://www.claycellar.co.uk/
CTM suppliers: https://www.ctmpotterssupplies.co.uk/
Pot Clay: https://www.potclays.co.uk/
Bath Potters: https://www.bathpotters.co.uk/
Tiranti (London base) https://tiranti.co.uk/
Blue Match Box (Reading) https://www.bluematchbox.co.uk/
I heard some studios offer a "take away box" with materials and tools to work with from home. I am very jealous for those potters who can still access their studio (mainly because they are work in isolation unlike in my studio, or they have a home studio set up)! Sadly as much as I would love to offer this to all of you, I am unable to access the studio due to the lock down. Nevertheless I am more than happy to answer any questions you may have! Feel free to drop me an email: firstname.lastname@example.org
In the meantime, enjoy spring and keep healthy!