Stains or underglaze colours

[Emma W]

Hi,

 

I've been trying to work out the difference between body & glaze stains and underglaze colours.

 

I need to colour terra sigillata for some of my work but also paint patterns on bisque for other pieces of work. Can I just buy one kind of stain to do both jobs?

 

If I get the glaze & body stain to use for the terra sigillata and just add frit for underglaze work this should be ok?

 

Will it really make that much difference?

 

Thank you

[neilestrick]

Stains are purchased as powders, and can be added to glazes, underglazes and clay bodies to color them. How much to add will depend on what you are adding them to. Test, test, test. Underglazes are purchased as liquids, and can be painted onto wet, leather hard, bone dry or bisque clay. They consist of a white base formula with stains added for color. A glaze covering, usually clear, is needed to make them food safe.

 

I prefer premixed commercial underglazes, rather than the frit/stain mix. Both work, but the commercial underglazes will stay suspended better, and brush better IMO. Plus they're super easy to buy and you don't have to mess with mixing them yourself. Some brands will fire up to cone 6, but many will not. I've had great luck with Speedball at cone 6, and they're usually the cheapest out there.

 

If you've got stain and frit, give it a try. You may like it just fine. If not, then invest in premixed underglazes.

[Chris Campbell]

The stain industry is huge and mostly caters to large manufacturers so when they call something a "body" stain it means you can pretty well mix it into clays and glazes with no adverse results. However, many of their others stains can also be used with clay and glaze but you have to test each one first and follow their guidelines for firing temps and ingredients.

 

Underglazes are the most forgiving and wonderful things! They fire from 06 to cone 10 and beyond with testable color changes. You can leave some unglazed or glaze over. If you let them thicken up you can use them as slips. They are being engineered for the 'color your pot' places so they just keep getting better and more consumer friendly.

 

You all might get sick of hearing this ...BUT ... Try it!! Test it!! There are no huge punishments for messing up. No pottery police will arrive to repo the clay. The reason we know what not to do is because we did it and failed ... Fall down seven times, get up eight times.

[TJR]

As always, I am going to be the dissenting opinion here. I prefer to mix my own stains and underglazes. Less expensive, more variety. A good recipe to start with is;

1part stain

1 to 3 parts frit.

1 part Bentonite.

The bentonite keeps the stain in suspension.

You can combine stains such as blue and green to get a light green.

As always, test,test,test on a tile, not on your masterpiece.

 

The most common Fritt for this is 3124.

TJR.