Posted on

Slip ‘n’Surfaces, Week 1

 

Hi everyone! Welcome to Slip’n’surfaces; a four week class on surface decoration.

Since I believe that surface decoration must enhance form and form should enhance the surface decoration – in short they must work together and compliment eachother, I decided I wanted to address a couple of key areas of functional pots. I  decided to do: 

Foot-of -the -week

Lip-of-the-week 

and also a Glaze-of-the-week    

as I have fielded a lot of questions about what glazes look good over and show off various surface decorations.

For my first demonstration I did again, the Eric Jensen Method of throwing out a slab. This is show in my blog entry Handbuilding week 1.

I brought in “sketches”  which are examples of work I did in 1997. I have an ancient web page with photos of the large work on it- to see them, click here.

The Lip-of-the-week was a simply rolled over lip – I don’t have a picture but in handbuilding or throwing you can take a thin lip and roll it over to give an extra thickness and a nice curve to the rim without adding weight to the pot.

The Foot-of -the -week was 3 “pods” – added feet to give some stability and height to an otherwise round bottomed drop dish.mayan-pot-ad-500-pinchpot-tripod-legs-animal-headThis tiny  Mayan pot shows the basic idea.

Glaze-of-the-week was actually  my favorite two glazes for over delicately carved slip and that was Shaner Clear and  Shino water.

 

Shaner Clear:

For porcelain* I give the pot a good wiping with a  very wet clean sponge so that it soaks up less glaze. I use a sponge so I have more control as to where the water goes (as opposed to just holding it under a faucet) I don’t want to soak a thin rim or it won’t have the ability to absorb any glaze.

Shaner Clear is a very forgiving glaze. Drips, dabs, patches all disappear and smooth out in the firing.

(all the rest of the photos on this blog entry are pots made by me)

Shaner clear thin over black slip
Shaner clear thin over black slip

The reason I thin it is that if it is on too thick it looks milky and makes the slips lighter in color- for example the black looks more like a blue-gray.

*Porcelain tends to absorb glaze more quickly and therefore more glaze than stoneware.

I prefer the shino water instead of Shaner clear over stoneware as clear leaves the stoneware a kind of dead-looking gray. Below you see that gray only in the lines cut through the white slip down to the stoneware underneath. It’s the only photo I could find with clear over stoneware as I dislike it so much.

small-birch-tray-clear-glaze

Shino Water:

 

Shino water often turns bare stoneware orange. The water leaves no thicker coating and so the texture of slip carving is highly visible. 

okay, right now I can’t find a photo of shino water over slip on stoneware but I have plenty of:

Shino over porcelain 

dsc00019Above is shino water over porcelain with black slip.

or porcelain slip  over stoneware can also go orange :stoneware drop plate with white layer of porcelain slip under black slip oak leaf -shino glazeThat is all for this week!

Posted on

Birches

Birch work  -Slip resist with sgraffito’d details..

Because porcelain tends to slump when it is so horizontal, I use stoneware in a slump mold. (I’ve found various delightful molds at the junk store.)painted-stoneware-in-slump-molds

As soon as I put the slab in the mold, I cover the surface with white slip.

freshly-slipped-slump-mold

Because I am working with two different clays- stoneware in the mold and porcelain slip- there is a slightly different shrinkage and I want the two clays to bond as much as possible when they are the wettest.

corner-detail

After the piece gets near leather hard, I tear up a bunch of newspaper strips and wet them and the surface of the tray. Wetting them helps them to stick down to the piece. The “frondy” edges of the torn paper also tend to stick more than a cut edge.

After they are down I apply a contrasting slip- in this case blue-

piece-with-newspaper-strips-under-applied-slip

and after letting it set up until it is no longer shiny but long before it dries, I pull up the strips.

removing-the-strips-of-newspaper

Here it is with all the strips pulled up. 

 after-strips-are-pulled

you can see places where the blue slip “snuck” under the paper- I will either draw over it or carefully scrape it off the white.

After that, I go back in with a drawing stick and define at least one edge of the tree  (thanks to Stephanie M. for that suggestion)and make all those little marks that are so distinctive to birches.

after-lines-are-added

This one (above)  is not even dry-certainly not fired or glazed. 

Glazing- I thought I would try a clear glaze on one

(here it is- some small  piece of the kiln stuck to it)

small-birch-tray-clear-glazeand on another, some soda ash water for a matte finish with possible orange flashing. 

long-birch-tray-shino-waterI have tried quite a few finishes on these trays. 

I’m trying to find something that enhances it by turning the carved lines brown (as opposed to the gray of the clear glaze above) but without changing the white of the birches. I’ve not been completely successful.

Here’s what I’ve got so far:

Under Celadon- glossy finish…y’know, I think I painted red iron oxide into the lines on this one and wiped it off.

birch-under-celadonUnder shino and wiped off lightly- matte finishbirch-under-shino-wiped-offunder Rutile Blue and (badly?) wiped off- matte finishbirch-under-rutile-blue-wiped-off

 

This next one below, took too long and I worried too much. This is shino wiped off and then clear painted on. If those two meet, they look awful together, bubbling, etc. NOTE* upper left corner, you can see where the slip did not bond to the stoneware- it can be a problem- and flaked off. Darn!

birch-shino-wiped-off-and-clear-painted-onbut of all the finishes (and this is just a little too matte) this is probably what I was shooting for.