Differences

[Nicky S]

If someone could please help me by simplifying  the differences for me  between “ slip ,  engobes and underglazes  “ I use both  porcelain and stoneware . And fire in an electric kiln

1) Slip is used mixing same clay body with stain and water . And applied to leatherhard  only .  (what other are ingredients could  be used in stains  for different surface effects ?)

2) Engobes are used only on leatherhard (?)

3)Underglazes can be used both on leatherhard  and bisque (?) .

Thank you so much Nicky 

[Bill Kielb]

Slips and engobes are generally very similar however many potters view slips as thinner and decorative for trailing and surface decoration. Engobes traditionally  form a barrier between a colored claybody to change the color. Colored slips and engobes usually use stains and oxides for color.
Stains are often oxides encapsulated or chemically bound in some fashion to preserve them during the firing process and to make them less soluble and less able to leach out of the final fired product. Underglazes are generally stains mixed with clay and perhaps fritt  as well as possibly something to improve brushability and drying. Underglazes perhaps can be thought of as ink for ceramics, most often colored by stains and are often painted on or applied by brush, stamp etc......

I think that came out right - Hope that helps, there is a bit of synergy in these items and in the case of stains, often used to color underglazes, engobes, and slips but generally can’t be painted on by themselves as they need to be mixed with a binder of sorts to stick to the ware.

Hope that is a start, there will probably be many insights here in short order. Oops, forgot rest of your question

slips and engobes generally are used during leather hard stage and must fit the body in drying shrinkage and firing shrinkage. They might be useable over bisque but often this compatibility Is difficult to achieve. Most often they contain some of, or  similar clay as that of the main claybody.

Underglazes contain a small amount of clay so they generally perform well on greenware as well as bisqued wares, they sinter in a bisque firing to become reasonably sturdy to handle and can be easily decorated over again or added to at this stage with little risk of rewetting  and smearing then overglazed.

Some folks rebisque and apply many layers of underglaze to get intricate multi layer designs before overglazing the final ware.
 

[Nicky S]

@Bill KielbHi Bill thank you so much for your  “expansive “ and detailed input ..... Really appreciate .
Tho clear I hope I understand ( have a slight learning disability )But at least now have something to refer too . 
Kind regards  Nicky

[neilestrick]

4 hours ago, Nicky S said:

@Bill KielbHi Bill thank you so much for your  “expansive “ and detailed input ..... Really appreciate .
Tho clear I hope I understand ( have a slight learning disability )But at least now have something to refer too . 
Kind regards  Nicky

Let us know what you're trying to accomplish and we can recommend the best material for that purpose.

[LeeU]

I just applied some black ^6  engobe to a ^5 bisque of a ^10 body that will be fired to ^5, w/a light glaze over it.  We'll see what emerges-may just get nuthin' .

[Nicky S]

4 hours ago, LeeU said:

I just applied some black ^6  engobe to a ^5 bisque of a ^10 body that will be fired to ^5, w/a light glaze over it.  We'll see what emerges-may just get nuthin' .

@LeeUHope it works out 

[LeeU]

Got nuthin'--all matte black. The c10 body was bisqued for a wood fire that will now never happen, so I went ahead and addressed the pieces for non-functional purposes just around my own yard/house. Did some experimenting w/the engobe, wax & glaze-nothing interesting happened.