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score and slip

updated wed 18 oct 06

 

John Britt on mon 16 oct 06


Marek,

Appreciate your comments and perspective,

John Britt
www.johnbrittpottery.com

mel jacobson on mon 16 oct 06


thank you snail for that report.

to add to her fine post.

one of the elements of making
pots that hold together is `timing`.

one clay body that you know and love,
making attachments when the clay is
perfect...or, the pot and the attachment
have the same amount of water. and, the
clay body is the same. the potter can
control that.
in other words, make attachments when the
clay is ready, not when you are.

as snail points out. high clay bodies
hold together better.

try this test.
add a brown stoneware handle to a
very dry porcelain pot.
you all know: it does not work.
they shrink at different rates and
the handle peels off.

if you cut a piece of clay in two
with wire and slap them back together
they will stick forever. no slip needed.

both surfaces have identical properties.
same amount of surface water.

a gentle application of spooze for example,
will just help the two surfaces reach the
same water content...it is an aid...not glue
as snail points out.

one of the most difficult of all studio processes
is timing.
knowing when to do things...you may know the how,
but the when is what professionals bring to the
studio. i know when to do things...it does not
always fit the family life style.
`no, we have to wait til the mugs are ready for
handles before we go to a film.` and, you all
know, if you leave them for 4 hours...it creates
all kinds of handle problems.

same for turning/trimming pots...do it when the
pots are perfect.
they hug the batt, the hold to the batt, the
knife slices like magic. it takes at least half the
time to get the job done.

i do not work with slabs, i make very few attachments
to my pots...mug handles are the most often attachment.
and, they are very forgiving.
mel
and marcia is right on point...the quality of your studio
humidity plays a big role in attachments working well.
same for breezes and drafts.

from: mel/minnetonka.mn.usa
website: http://www.visi.com/~melpots/

Clayart page link: http://www.visi.com/~melpots/clayart.html

Marek & Pauline Drzazga-Donaldson on mon 16 oct 06


To each their own - without a doubt - and after 15 years of no scoring I =
will stick to that method.=20
Depends on so many variables, but I will utter again about Newspaper. =
Having built your masterpiece,
cover it in Newspaper, and in every condition I have worked in with the =
variety of clays etc. Having problems - wrap it in Newspaper. Been using =
this little gem for over 15 years - it is a winner.

Scoring has got its place - in other Studios. I disagree with snail in =
that slip does Bond, read some of Ivors messages on that one.
This all came about as I saw absolutely no reason to score and slip =
freshly thrown clay. Do you score and slip when you are coiling with =
fresh clay? No of course not.

Do what you are happy with, but please do try and push the envelope. I =
agree with Tradition, but only when I push it beyond its boundaries, =
this is how we learn, and my 15 years of no scoring has taught me I do =
not need to score period, and I would also advise others to experiment =
with all conditions of clay to suit the way you work.=20

I work fast - I do not cut corners - and effectively, and will continue =
to trrial and absdorb other ways of doing to suit my method of working.

As snail also said, both methods are right - it is down to you.


Happy potting Marek


Hand made Architectural Ceramics from No9 Studio UK www.no9uk.com
Fully Residential Pottery Courses and more at Mole Cottage =
www.moleys.com
"Tips and Time Travel from a Vernacular Potter" reviews on =
www.keramix.com
an irreverent point of view after 35 years in the game Marek =
Drzazga-Donaldson =20
Assemble a dragon finial at www.dragonfinials.co.uk
Free Works and Mole Cottage DVD's and Video content on all the sites

Jennifer Boyer on mon 16 oct 06


The reason there are so many different ways of joining clay pieces is
that there are just as many different circumstances!

Many years ago( 1980?) I attended a workshop given by Byron Temple,
who was quite a character. He went on and on about the new fangled
and HIGHLY suspect idea of covering pots with plastic dry cleaner
bags, which had been brought up by some of the attendees. He thought
it was bogus..... Later he talked about his studio in Pennsylvania, a
mossy old stone building with foot thick walls: Jeez, the guy was
working in one big damp box! No wonder he thought plastic was
irrelevant. ....at that point I was working in a basement studio next
to the wood furnace, heated by forced hot air ducts. Noone messed
with my box of plastic dry cleaner bags!

Jennifer, whose current studio is quite draft free....but I still
have my plastic at hand. Helps with the timing.


On Oct 16, 2006, at 7:59 AM, mel jacobson wrote:

> thank you snail for that report.
>
> to add to her fine post.
>
> one of the elements of making
> pots that hold together is `timing`.
> water.
>

*****************************
Jennifer Boyer
Thistle Hill Pottery
Montpelier, VT
http://thistlehillpottery.com
*****************************

John Britt on mon 16 oct 06


Marek,

I am with you on the newspaper. It has helped me with drying plates
properly.

I applaud your methods and certainly would never attempt to convince you
otherwise.

But as for the details of not scoring, I realize that there are many ways
and variables that are often left out when people talk about their ways of
working. If you do work fast with freshly thrown pieces then it is often
unnecessary to score. But what if you work slowly? What if you work
leather hard? Or if you work with very thick pieces that are in varying
states of dryness? What if you work in a group studio with a heater that
is out of your control causing uneven dryness? In these cases I think even
you would score the piece before using newspaper.

I appreciate your ability to work quickly and eliminate scoring but for a
lot of people that is simply not feasible.

Just my opinion, as I have seen many attachments fall off in my lifetime
by students taken in by overarching generalizations that fail to mention
the key facts, like in your case, working fast and wet.

Trying to relax,

John Britt
www.johnbrittpottery.com

Vince Pitelka on mon 16 oct 06


Marek wrote:
"Scoring has got its place - in other Studios. I disagree with snail in that
slip does Bond, read some of Ivors messages on that one.
This all came about as I saw absolutely no reason to score and slip freshly
thrown clay. Do you score and slip when you are coiling with fresh clay? No
of course not."

Marek -
The above is misleading. In coil construction you do not need to score and
slurry if you smear the coils together, as any tribal potter does, because
that efficiently intermingles the platelates and produces a very strong bond
(as strong as any thrown pot). If you push two pieces of clay straight
together, there is no intermingling of platelates unless the clay is very
wet, and you just create a perfect fracture plane. If the clay is wet, it
sometimes works, especially with a little movement or twisting motion to
encourage the intermingling of platelates. As I mentioned in another
message, the whole point is to get the platelets to interlock.

Remember that many of us are assembling leather hard components, or
attaching soft clay handles to leather hard pots. With most claybodies,
this doesn't work without thorough scoring and application of slurry before
joining.

Of course slip can create a strong bond, regardless of what Ivor has
written. If there are two scored surfaces, and slip is used as a joining
medium, it provides the intermingling of platelets needed for a strong
joint. I can take a series of beveled stiff slab pieces and assemble them
into a box form with thorough scoring and slurry but very little pressure,
and the form will never come apart in drying or firing. The slip bonds the
adjacent pieces very efficiently.

I think we can agree that some wet plastic claybodies join particularly
aggressively without scoring and almost any soft plastic clays will join
securely without scoring if twisted or smeared together, but if the clay
has stiffened at all, as in much slab construction or other processes where
pre-made, stiffened modules are assembling, then scoring and slurry is
necessary to get a strong joint.

Hope that clarifies things -
- Vince

Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/

Allyson May on tue 17 oct 06


I'm so glad someone finally mentioned Lana Wilson's Magic Water. I do a =
lot of stiff slab construction and Magic water has really solved my =
joint crack problem. I do score both edges with a serrated metal rib, =
paint both with Magic Water, slide/wiggle together and then paddle. On =
functional ware I use porcelain and the handle attachments were a =
problem until I started using Magic Water. I usually don't score here, =
just Magic Water and a little wiggle. No cracks!
Peace,
Allyson May
Stoney Creek Pottery
Bloomington, IN

Snail Scott on tue 17 oct 06


On Oct 16, 2006, at 9:10 AM, Marek Drzazga wrote:

> I disagree with snail in that slip does Bond, read some of Ivors
> messages on that one.
> This all came about as I saw absolutely no reason to score and slip
> freshly thrown clay.


Most wet clay will join without scoring, because
it is soft enough to interlock with just the friction
between the two parts. Some clay bodies won't
allow for this even when fresh, and need special
effort always. If your clay doesn't need scoring,
though, then it doesn't - that's exactly what I meant
by knowing your clay.

Simply putting soft clay together won't make a
joint, as you know. When you lute or squish the
clay, though, you ARE essentially scoring it, as
the particles scrape against each other and
intermingle.

Most of my work is coiled, and I seldom score
between rows. The only time I score is between
one day's work and the next, or after an extended
break, when I can't rely on equal moisture content.

Scoring can become critical when joining leather-
hard sections, or when moisture levels are not
quite equal. Slab work in particular requires
excellent joining techniques, including scoring,
since luting is often not feasible with stiffer clay.

When I previously said that 'slip is not glue', I was
oversimplifying for the sake of making the point -
that just applying the stuff does not make a joint.
Further, more slip does not produce a better joint.
'Just enough' slip produces a better joint. (It IS like
glue in that way.) And a 'shimmy' as parts are put
into place does wonders for strength, as it forces
out the excess slip and air bubbles, leaving a good
tight bond of mostly clay.

Slip may have molecular-level bonding capability;
I'm not qualified to say, but water is amazing stuff.
Ivor may well be right on the microscopic level.
Slip does have physical properties on the macro-
level, too, though, which are not negated by any
other properties it might possess. Its water-lubricated
particles can slide right up against the clay and fill
any waiting interstices. (Smooth clay is kinda rough
already; scored clay just improves on that - and
remember, scoring is a surface process, not an
excavation. Even shallow scoring involves zillions
of clay particles.)

This goes for all the 'souped-up' slips
like spooze, too. Vinegar, sodium silicate, sugar
syrup, and such all contribute useful properties,
but the slip still contains clay. 'Magic water'
is not a miracle cure, either, if you don't pay
attention to the properties of your materials.

No, not all joints require scoring, or slipping, and
that's exactly my point - to consider your process
as a thinking being, not an automaton, repeating
the score-and-slip ritual.

-Snail

p.s. I second Marek's advocacy of paper as a
cover during controlled drying. No condensation,
gradual evaporation, improved evenness of drying
and good protection from drafts. I do believe that
the plastic bag is the single greatest new ceramics
tool of the last millennium, but it's not always
the right tool for the job.

-S.

Marek & Pauline Drzazga-Donaldson on tue 17 oct 06


Dear John,

thank you for your comments. I work fast, I also work with leather hard =
clay - no scoring and no cracking. If drying too quickly is a problem =
then the Newspaper trick is invaluable, it really is a life saver. When =
I join the clay together I do move the clay about, I do not stand on =
ceremony.
I also appreciate that my methods are not for everybody, they certainly =
are for me, and I wil always help others to find their methodology - it =
is part of my character to Pot by the seat of my Pants, and I find that =
I make mistakes when I get out of character - so always be true to =
yourselves is a mnemonic on my lips.
There are as many methods of doing as there are Potters, just find your =
flow.


Happy potting Marek


Hand made Architectural Ceramics from No9 Studio UK www.no9uk.com
Fully Residential Pottery Courses and more at Mole Cottage =
www.moleys.com
"Tips and Time Travel from a Vernacular Potter" reviews on =
www.keramix.com
an irreverent point of view after 35 years in the game Marek =
Drzazga-Donaldson =20
Assemble a dragon finial at www.dragonfinials.co.uk
Free Works and Mole Cottage DVD's and Video content on all the sites