how would i make this?

[missholly]

im trying to make a shaving bowl. glazed on the inside and an outside with a sandy texture.

is there any kind of grog i can buy and just roll a wet bowl in it so it sticks, then fire? and will it be waterproof, or should i use a matte glaze?

[Chris Campbell]

There are a lot of ways to do this but the simplest would be to roll out a thin piece of clay, let it dry, then crush it to the desired size. Then, when the bowl is almost cheese hard, paint on a thin wash of your throwing slurry or slip and quickly roll the outside of the bowl in it. Glaze the inside and the rim. If you want texture that goes into the surface, I recommend pressing in a filter pad that is used in humidifiers ... It leaves a sandy looking impression on wetter surfaces and slipped surfaces.

[weeble]

Or just CAREFULLY wipe the surface with a damp sponge when its bone dry, if your clay has any sand or grog in it, you'll remove a layer of the finest particles and leave just the groggy stuff! This takes a delicate hand, you don't want to wet the piece, just remove the surface layer. Look up 'water etching' for more info.

[Mossyrock]

I remember a workshop I attended where the instructor used a fire clay (AP Green I think) on a piece he was throwing. When he had the piece nearly thrown, he heavily coated the outside of it with the fire clay. Then he finished throwing from the inside only, not touching the outside so as not to disturb the fire clay. The result was a gorgeous 'dry creek bed' sandy effect because as the piece was pushed out from the inside, the fire clay split and cracked in all sorts of interesting ways. It was reduction fired to cone 10.....no glaze on the outside. Very interesting piece.

[missholly]

chris, that will totally work!

thank you so much!

 

and, ive never worked with a matte glaze.

the inside of the shaving bowl needs to be shiny glazed for water protection, and the outside is to be matte. but is a matte glaze waterproof too?

[missholly]

actually, a matte clear. is that even possible? or necessary?

[Idaho Potter]

Water protection is at its best when clay reaches vitrification. So if you are working with mid-fire clays, that means firing to the cone (5 or 6) for that clay. I have several cups I've purchased from other potters that are glazed inside and on the lip, but no glaze on the outside. They don't leak.

 

Shirley

[OffCenter]

chris, that will totally work!

thank you so much!

 

and, ive never worked with a matte glaze.

the inside of the shaving bowl needs to be shiny glazed for water protection, and the outside is to be matte. but is a matte glaze waterproof too?

 

 

You should never depend on the glaze to make anything waterproof. Even if the glaze fits well enough that you can't see any crackle, there is very likely some there and water will leak through. Granted, it may be a very slow leak but it will leak. The clay you use should be mature and not leak with no glaze on it at the cone you fire it to. Any time you use a new clay you should test for leakage to avoid making pots that are going to ruin grand pianos.

 

Jim

[Mart]

Gets some stoneware clay with lots of grog in it. About 40% and 0-0.2 mm grog is probably good enough.

 

 

1. Make your bowl, make it smooth inside (metal rib)
2. let it dry leather hard
3. Take your favourite scraper and scrape the outside so grog is coming out.
4. Fire
5. Glaze it inside
6. Glaze it outside and take that scraper of yours and scrape the outside once more
7. Fire

 

This bowl is really smooth inside and nice and coarse outside.

 

[missholly]

mart, very cool!

 

well, its just a shaving bowl, so there will only be water in it for a short amount of time, probably every day or so.

i guess im not really worried about it being water PROOF, i just didnt want it to fall apart on him years from now.

he wants the outside rough and sandy like so hell have a good grip on it. i havent really tested unglazed ceramic material with water to see what happens.

 

im thinking of what chris said about using a clay wash and attaching (probably raw grog) to the outside.

hopefully thatll fire and hold steady without flaking off too much.

if it works and is solid, i guess i can just underglaze the whole thing, then clear glaze the inside.