vince pitelka on fri 31 mar 00
------------------
As some of you may have heard, I brought 1000 copies of my handout and ran
out. For those who didn't get one, and for those who were not there, here
it is in full. I hope it fits into one Clayart message. If not, I can post
more installments. Best wishes -
- Vince
Appalachian Center for Crafts - Tennessee Tech University - 1560 Craft
Center Drive, Smithville, TN 37166. 615/597-6801
Tool Doctors Presentation - NCECA 2000
Vince Pitelka - wpitelka=40tntech.edu
Finding, Making, and Improvising Clay Studio Tools and Fixtures
It is always a joy to use good tools, and invariably the work we make
is greatly affected by the tools we use. Most tools are extensions of the
human hand. Our hands are all physically similar, but the way we train them
and use them is very different. Consider that every commercially-made clay
tool was designed for someone else's way of working, with
their particular needs in mind. As such, each has certain advantages, but
also built-in limitations. Some may be well-adapted to your needs, while
others will be awkward or even useless. When you design and make a tool
yourself, you determine the possibilities and limitations.
Tooling Up: The Tools to Make the Tools
For any serious studio artisan, a good familiarity with general
hand-tools and simple construction/fabrication processes is a great
advantage. You don't have to be a journeyman carpenter or welder, but at
the same time, don't avoid these skills. As you become proficient in clay,
you can also be learning the rudimentaries of working wood and metal. Over
time, build your inventory of hand tools and power tools. When buying hand
tools, always seek those that feature a life-time guarantee. Tooling up is
a mind set, almost a religion, usually continuing over a lifetime. To many
people, including myself, having and using the right tool for the job is a
great joy, and a good-quality tool, well-cared-for, is a lifetime
investment. Buy a good tool now and then, and it will not cost much over
time, and the benefits are so rewarding.
In addition to the normal pliers, screwdrivers, allen wrenches, socket
wrenches, open-end wrenches, pipe-wrenches, etc., which allow you to
maintain and repair your studio fixtures and equipment, there are additional
tools which serve special purposes in the studio, or will assist you in
making your own studio tools and equipment. An assortment of fine and
coarse-tooth files will allow you to sharpen and shape wood and metal
surfaces on ribs and trimming tools.
Punches and chisels serve a wide variety of uses in shaping and cutting
materials for studio tools, and of course the wide brick-chisel is essential
for building and repairing kilns. A good stationary vise need not cost more
than =2420 or =2430, and will allow you to hold materials that you are =
cutting,
grinding, or shaping.
The most basic portable power tool in the studio is the electric drill.
Aside from all the uses in making tools and fixtures, you can use it with a
mixing attachment like a Jiffy-mixer for blending glazes, slips, slurries,
plaster, and mortar. Everyone is seduced these days by cordless drills,
and they are excellent for construction or general studio maintenance, but
they do not develop the speed necessary for use with a drill-mounted mixer.
For about =2460 you can get a decent 110-volt 3/8=22 variable speed Makita,
DeWalt, Bosch, or Ryobi and it will last a very long time. Make sure it
develops at least 1200 RPM maximum speed. If you want to use a large
drill mixer to mix claybodies as slurry and stiffen them to plastic
consistency, you will need to spend =24150 for a good 1/2=22 drill, plus =
=2460 or
so for a large drill-mixer.
A =2475 4=22 angle-head grinder serves a multitude of grinding and
finishing tasks, including cleaning kiln shelves.
A circular saw and saber saw will allow you to build all sorts of
wooden studio fixtures. They need not be expensive models, but get the best
ones you can afford. If you have the chance to buy used ones, seek the
high-quality brands mentioned above, or a Milwaukee, Porter Cable, Skill
commercial, etc, and plug them in and turn them on to make sure that the
bearings are OK and they operate smoothly.
A stationary bench-grinder, costing less than =24100, will allow you to
sharpen your trimming tools (and all sorts of other household tools) and to
re-shape your wood modeling tools. An abrasive flap-wheel on one end of the
bench-grinder is an excellent tool for shaping and smoothing wood or metal
tools, and is also a superior tool for smoothing the bottoms of
fired pots.
If you want to get serious about fashioning your own wooden tools, you
may wish to invest about =24100 in a small stationary disk/belt sander, and
around =24300 for a band saw. The disk/belt sander has both flat and curved
surfaces needed for shaping wooden tools. The band saw allows you to cut
out basic shapes for all sorts of purposes, and will also allow you to make
your own throwing bats.
To drill accurate mounting holes in your bats you will need access to a
drill press, which is a very handy stationary power tool for many
applications. A good small table-top drill press will cost you about =
=24100.
A simple drum-sander attachment will also allow you to shape wooden modeling
tools on your drill press.
It is not at all difficult to acquire basic welding and fabricating
skills. With as few lesson and some practice, virtually anyone with a
steady hand can become a good welder. With these skills you can build your
own ware carts, welded kiln frame, hinged kiln door, and a multitude of
special fixtures, brackets and tools around the studio. A small 220 volt
A.C. arc welder capable of at least 150 amps welding current will cost you
about =24250. If the idea of welding and fabrication appeals to you, and =
you
envision using these skills frequently, it will be worth your while to spend
another =24250 on an oxy-acetylene welding set with welding and cutting =
tips.
Don't settle for anything except a name brand, such as Victor or Airco. A
power abrasive cut-off saw, costing about =24150, is very handy for steel
fabrication projects, but it should not be viewed as a substitution for the
oxy-acetylene cutting-torch, because the cutoff saw will only make certain
kinds of straight and angle cuts. For finishing your welded and
fabricated work, the small angle-head grinder mentioned above is ideal.
A decent air compressor will allow you to spray glazes, and to use a
wide range of pneumatic grinders, sanders, etc. Avoid direct-drive
compressors, because the cylinder is made from aluminum or pot-metal in
order to dissipate heat more quickly, and they do not last as long.
Instead, purchase a compressor with a cast iron cylinder sleeve. These
compressors always have separate motor and a belt drive. Take a magnet with
you when shopping for compressors, and check the compressor cylinder to make
sure it is cast iron. If the magnet sticks, the cylinder is iron and will
last forever.
Of the many spray guns offered through ceramics suppliers, there are
only a few which are practical and effective. The external mix guns are the
best, such as the =22Critter,=22 the Bailey, or the more expensive Paasche
unit. These are all identifiable by the vertical tube extending up from the
glaze reservoir in front of the air nozzle. The =22Critter=22 has the =
advantage
of accepting ordinary mason jars. Avoid the internal mix guns sold by some
ceramic suppliers, as they tend to clog very badly.
For a cheap and serviceable spray gun, consider the standard cheapo
guns available from budget tool dealers and discount stores for around =
=2430.
They are external-mix guns, but the glaze passes into the head of the gun
and emerges from a small orifice in the center of the airstream. This
simply demands that the gun be very well cleaned after each use.
Many people like the HVLP (high volume low pressure) spray guns, which
are a little more expensive, but over-spray is greatly reduced, which will
save you money in the long run.
For thickly-sprayed or spattered glaze and slip effects, and for
spraying refractory coatings on kilns, small sandblasting guns work very
well. These are available inexpensively from discount tool catalogs and
auto supply stores.
Avoid airless spraying systems, like the popular Wagner guns, as the
abrasiveness of glazes and slips will almost immediately kill the pumping
mechanism.
Hand Tools
Bats for Throwing: For making quantities of perfect throwing bats very
cheaply you will need access to a skill-saw or table-saw to cut full sheets
of material into squares, a bandsaw to cut the squares into circles, and a
drill-press to drill the bat-pin-holes. You can make bats from tempered
Masonite, plexiglass, PVC sheeting, or marine plywood, but the best ones
are made from Medex waterproof particle board. If you want to do this,
E-mail me and I will send you instructions.
Canvas as an Alternative to Bats: When throwing wide low forms such as large
bowls and plates, rigid bats are the best system. Many other forms,
especially those which are cylinder-based, may be thrown on canvas squares,
allowing easy removal from the wheel without touching the pot. Use any
heavy canvas. Coat new canvas squares with a thin skim coat of
gritless slurry, and let them dry. In use the residual slurry from the
previous pot will be adequate, but they must be dried completely each time.
Smear a little gritless slurry over the wheelhead, and squeegee the canvas
in place with a rubber rib. When you finish the pot, run the cutoff wire
under the canvas, grasp one corner and pull the piece onto a triangular
concrete-finishing trowel, and onto a wareboard.
Bisque Stamps and Roulettes: For bisque stamps, I like to throw knob-shapes
off the hump, let them get leather-hard or bone-dry, and then carve patterns
or textures into the contact surface. They can be carved dry with files,
hacksaw blades, or a Dremel tool.
For making roulettes, raise up a column of clay of the desired diameter
on the wheel, cut the top off square, poke a bamboo cocktail skewer
vertically into the center of the column, and cut in from the side with your
needle tool until it touches the skewer. Lift needle tool and skewer, and
deposit the resulting disk on a board. Repeat, varying the thickness of
the cut disk for different roulettes. When the disks are leather-hard or
bone dry, carve a pattern or texture in the outer surface. Drill an
appropriate hole through the center for an axle or handle, and bisque-fire
them.
For an excellent roulette handle, purchase cheap caster wheels from the
hardware store. Grind the swaged end off the center axle, and remove and
discard axle and wheel. Purchase a small screw and nut to fit the axle
hole, mount the roulette in place of the wheel, spaced with washers if
necessary, and attach with the screw. Mount on an appropriate wooden
handle.
Japanese Cut-Off String: When throwing off the hump, Japanese potters use a
loose-end cut-off string with a single handle. For best performance it must
be made in a specific way. Take a short length of dowel, drill a hole
through one end, and tie on a 12=22-length of upholstery thread, so that you
have two 6=22 lengths hanging free. Place the handle in a vise, or poke it
into a large lump of stiff clay, so that the threads hang loose. Examine
the threads closely, with a magnifier if necessary, to determine the
direction they are twisted, and twist them separately further in the
direction they are already twisted. After twisting them as much as you can,
combine them at the ends and twist them in the opposite direction together.
Without releasing them, tie a small knot in at the free end, and trim off
any uneven length beyond the knot. If done properly, you will have a string
composed of two permanently twisted threads, which when pulled through the
clay will leave a surface which is slightly =22corrugated,=22 admitting air =
into
the
joint and allowing the thrown form to easily be lifted off the hump. It
also leaves a very pleasing pattern on the bottom of the vessel.
To use, make a shallow groove in the thrown form where you wish to make
the cut. Stretch the string out straight away from the tool in the
direction the wheel is turning. Bring the base of the string (close to the
handle) up against the groove in the turning form, and let go of the loose
end. The turning clay form will draw the string around in the groove.
As soon as this happens, pull the handle towards you without raising or
lowering it, and the string will cut off the form perfectly level every
time.
Cut-Off Wires: Great cut off wires can be made from stainless steel fishing
leader, available from good sporting-goods stores, from =22Tiger-tail=22 =
wire
used for stringing beads, available from jewelry suppliers, or from
stainless steel flying lines for control-line model airplanes, available
from Sigg Manufacturing in Montezuma, Iowa, 515/623-5154, or
=3Cwww.sigmfg.com=3E. The latter is multi-strand braided stainless-steel
aircraft cable in a range of thicknesses. The .021=22 is appropriate for
normal cutoff wires. I use wire as thin as .012=22 for cutting thin slices
off of patterned colored clay loaves for my clay marquetry work. Making
your own cut-off wires allows you to choose the length. Tie the wire
securely
between two short pieces of dowel or two bisque-fired beads, or use the
handles from broken cutoff wires.
Wire Frame for Cutting/Blending Clay: Many ceramic artists have a stretched
wire permanently installed on their wedging table, to cut and combine clay
in the wedging process, and to cut the wedged lumps into smaller pieces.
But this wire is often in the way when you want to use the table for other
purposes, and it is often an advantage to use such a
stretched wire elsewhere in the studio. It is a simple matter to build a
portable wooden frame with a stretched wire across the top, which may be
clamped down anywhere in the studio. Always use multi-strand stainless
steel wire, as described above in the section on making your own cutoff
wires.
Fluting Tool: A very effective fluting cutter can be made from 1 =BD=22 by =
6=22
strips of 18 to 22-gauge sheet metal. In the center of the strip one inch
from one end, drill a hole of a size corresponding to the width of flute you
want to cut. With sturdy C-clamps, clamp two strips of hardwood, or two
lengths of steel flat-bar along each edge of the sheet metal strip, so that
section exposed down the middle along the length of the strip is just barely
wider than the drilled hole. Better yet, clamp one edge in a vise, and
clamp strips along the other edge. Take the drill-bit out of the drill and
insert the blunt end in the hole. By forcible tilting the drill-bit as far
as you can towards the end of the strip you will distort the hole, raising
one edge of the hole and lowering the other edge, forming a cutting edge
very much like a cheese-grater with only one hole. For larger drill sizes,
or for thicker sheet-metal you may have to use a piece of pipe or steel
tubing as an extension handle over the end of the drill-bit for increased
leverage. The strips clamped along the sides are absolutely essential,
because without
them, when you try to tilt the drill-bit and distort the hole, the entire
strip will simply bend. The wood or flat-bar strips and/or vise clamped in
place keep the sheet-metal strip flat.
Clamp the strip flat in a vise, and with a round file sharpen the
cutting edge inside the hole. With a flat file, remove any burr left on the
outside surface of the cutting edge. Be sure that you sharpen the edge that
will cut as the tool is pulled towards you. Sand the outer edges of the
strip to remove any sharp burrs.
To use the fluting tool, drag the raised edge of the hole along a
leather-hard clay surface, cutting out a smooth even flute. The flat areas
around the hole will control the depth of cut.
Glaze Mixing Whisk: A large wire whisk for hand-mixing glazes or slips can
be easily made from a piece of heavy wooden dowel or tree-branch 1 =BD=22 in
diameter, four 36=22 lengths of 1/8=22 brass or stainless-steel welding rod,=
and
a 1 =BD=22 stainless steel hose-clamp (available from any auto parts store).
Cut a length of dowel or branch at least 10=22-long for a handle. With a
pencil, lay out four lines across one end of the dowel, dividing it into
eight pie-slices. Along each of these lines, with a hacksaw cut four slots
2=22-deep straight into the end of handle. Along each of these slots, on =
the
end-face of the handle, drill an 1/8=22 hole 2=22-deep, 1/4=22 from the =
outer edge
(total of eight holes). Bend one of the welding rods over a 4=22-diameter
form (a piece of pipe, a can, etc.) to create a U- shape with equal-length
legs. Insert the legs of this U-shape into a pair of opposite holes in the
end of the handle. Repeat with the other three pieces of welding-rod. Slip
the hose-clamp over the handle and tighten securely over the slotted end of
the handle =BD=22 from it's end to securely lock the rods in place. For =
general
glaze mixing, this whisk works much better than a stick, and is especially
useful for mixing glaze in a wide shallow pan, such as one might use for
glazing plates and bowls.
Drill Mixer: Most of you have used the standard commercially available
mixing attachments for electric drills, useful for mixing slips and glazes.
If you are on a tight budget, go to your local home improvement superstore,
and examine the range of mixing attachments they have. These will range
from very small ones for mixing paints, to huge ones for mixing drywall
mud. All but the largest ones are useful in ceramics. Examine any possible
mixing attachment closely to make sure it has no abrasive surfaces which
might erode through the plastic bucket.
Glaze Sieves: Scour flea-markets and local hardware dealers for fine-mesh
screen, or order it from Direct Metals Co. LLC, 1200 Chastain, Bldg. 201,
Kennesaw, GA 30144-5586, 800/711-4939, or from Perforated Metals Plus, 600
Royal Rd., Michigan City, IN 46360, 800/220-8952. If you happen to find
some very fine-mesh screen, you can always check the mesh size with a strong
magnifying glass - 80 mesh screen simply means 80 openings per inch. You
can mount the screen
on a simple wooden frame, or there is a great way to make an excellent
sieve-body from a plastic bucket. Stop by my table to see how.
For straining small amounts of glaze or slip, small fine-mesh kitchen
strainers work great.
Knives for Clayworking: All sorts of knives are handy in the clay studio. I
have found that cheap, thin steak knives work very well, and can be shaped
to your needs on a bench grinder.
For general piercing and cutting of leather-hard clay, a common
razor-knife works best - the type with the 1=22-long blade tapered to a fine
point, available in any stationary store or art supply store. With any
knife for use in clay, take a piece of stone or high-fired clay and dull the
blade. It is the thinness of the blade that counts, not the sharpness of
the edge.
Clay Saw: There are times when one must cut hard-leather-hard or bone dry
clay. The normal piercing saw made for cutting drywall works great. Any
saber-saw or Sawzall-blade can be glued in a wooden handle. These have the
advantage of cutting on the pull-stroke, which seems to work better with
clay.
Drills for Clay: Cheap drill-bits do a good job of drilling leather-hard
clay. Purchase drill bits of all the sizes you want, along with appropriate
diameters of wooden dowel for handles. Mount a drill bit in an electric
drill, and drill a hole centered in the end of an appropriate piece of
dowel. Remove the drill from the drill-chuck, and glue the blunt end into
the dowel. Repeat with all the other sizes. Don't make the handles larger
in diameter than they need to be, because the smaller sizes are easier to
spin between the fingers.
Hole Punches: For making holes in soft clay, good hole-punches can be made
from any thin-wall metal tubing. The brass tubing used in model-making
works well. In plumbing shops you can get thin-wall brass or copper tube in
a variety of sizes. Depending on how you plan to use the hole punch you can
cut either a straight or a bevel end in the tubing, and
unless the metal is extremely thin, carefully sharpen the end on a bench
grinder. Cut a piece of appropriate-sized wooden dowel to poke out the cut
slugs of clay, and keep it with the punch. If you want to mount your
punches in a wooden handle, make the tube extend all the way through the
handle, so that you can still poke out the cut slugs.
Modeling Tools: You can find or make a wide variety of wooden modeling tools
useful in throwing and hand-building. Some existing wood shapes work well,
such as popsicle sticks, tongue depressors, wooden spoons, chopsticks, and
bamboo cocktail skewers. Wooden dowels, strips of hardwood (often available
for free from furniture or cabinet shops), or strips split from a length of
bamboo can be cut and shaped to the desired contour with a saw, carving
knife, sander, grinder, file, and/or sandpaper. A length of 1/4=22 dowel
sharpened in a pencil-sharpener and sanded to a slightly dulled tip (or a
dull pencil) is especially handy for signing the bottoms of pots.
Needle Tools: Make your own needle-tools with a length of 3/8=22 wooden =
dowel
and a sturdy sewing needle. With very small needles, clamp the point-end of
the needle securely in a bench vise or hold it in vise-grip pliers, and tap
the dowel-handle onto the blunt end of the needle shaft. For larger
needles, drill a 1/16=22 hole in the end of the dowel, and glue the
needle shaft in place.
Paddles and Anvils: Both thrown and handbuilt forms may be shaped and
resolved using a paddle on the outside, sometimes with a heavy rounded
=22anvil=22 held in a corresponding place on the inside. Paddles can be cut
from any kind of wood, but hardwood has more weight.
The anvil is normally a rounded river stone, but a rounded hardwood
block works well, or even some stiff clay wrapped in canvas. If you do not
have access to rounded river stones, make your own with clay, poke holes
deeply in them with a needle tool (so they do not blow up in the firing),
sand them smooth when dry, and bisque-fire them.
Patterned Paddles: A layer of string, cord, or rope wrapped around a paddle
will produces interesting pattern effects. Sawed groves or holes drilled in
the surface of the paddle also create interesting patterns. Or, make a
textured tile, bisque fire it, and cement it to the surface of a wooden
paddle. A dry corn-cob makes a very good small texturing paddle.
Ribs: A wide selection of rigid and flexible ribs are useful in both
throwing and handbuilding. Flexible ribs can be made from old credit cards,
CDs, plastic food containers, plastic bucket lids, thin sheet metal,
sidewall from a tire, Teflon sheeting, canvas or rubber machine belting, or
any other slightly flexible material. The thinner, softer materials may be
cut with ordinary scissors, while the thicker, harder materials may require
a pair of sheet-metal shears or a bandsaw or scroll saw. Plastic
applicators used for automotive body putty, available in auto-supply stores,
make very good semi-flexible ribs, and are easily cut to smaller sizes.
You can make rigid ribs out of Formica scraps, Masonite, Plexiglas,
plastic sheeting, thin slices of hardwood, coconut shell, or dried gourds.
All of these will require at least a coping saw or hacksaw, and for best
results a bandsaw or scroll saw.
Profile Ribs: Any rib may be altered by carving, cutting, sawing, or
grinding a profile on one edge. When pressed against the outside wall of a
well-lubricated spinning thrown form (with corresponding gentle sponge
pressure on the inside), or when dragged over any well-lubricated clay
surface, the profile will create a contour band, similar to ornamental
molding.
Combing/Texturing/Scoring Tools: For applying a combed texture, use pieces
cut from ordinary combs, a fork, a triangular pastry-texturing tool, an
applicator trowel for tile adhesive, or sections cut from band-saw or
saber-saw blades. For combing or scoring clay surfaces, the stainless steel
version of a pastry-texturing tool or sections of saw-blades work very well.
Rollers and Rolling Pins: It is not practical to make your own rolling pin,
but there are some considerations when selecting one. Get the best
available, and don't settle for one with fixed handles, where the entire
unit is made from a single piece of wood. Purchase a good heavy rolling pin
with plastic bearings or ball bearings. The larger the diameter of the
roller, the more clearance for your fingers when they are wrapped around the
handles. You will find the best prices at restaurant supply and kitchen
stores.
Smaller rollers are very handy for a variety of tasks in the studio.
The standard wallpaper seam-roller, available from decorating and building
stores is an inexpensive and useful tool. Get one with a wooden roller if
possible, because it may be shaped on a bench grinder when necessary. Small
printmaking brayers, such as are sold for linoleum block work,
make excellent small rollers for general studio use. All sorts of other
rollers, available at flea markets, second-hand shops and kitchen stores,
may prove very useful, depending on what kind of work you do. A very handy
small roller can be made from a caster wheel mounted in a wooden handle.
Scraping and Abrading Tools: We are all familiar with the standard stainless
steel rib, which works well for scraping leather-hard clay. A broad range
of tools and supplies work very well for scraping or abrading the clay
surface. With any scraping tool, frequent sharpening will help. Do not
sharpen clay scrapers at an angle like a knife blade, because they will
just dull very quickly. Hold the scraper at 90 degrees to the surface of a
sharpening stone or a piece of silicon carbide kiln shelf, and rub
vigorously.
One of the most common abrading tools in contemporary ceramics is the
Surform file or plane, a woodworking tool from the Stanley Tool Company. It
has a blade like a cheese-grater, and is available form most good hardware
stores. Some suppliers carry imitations, which seem to work just fine.
All sorts of scrapers and knives found in building-supply stores and
second-hand shops may work for scraping and abrading clay surfaces. Cheap
plastic or metal putty knives and scrapers are very useful.
Slip-Trailing Vessels: Standard fine-pointed hair-tint bottles, available
from the cosmetics counter in your drug store, work quite well as
slip-trailing vessels, but the tip is rather short, and better results may
be achieved by using nose-ear syringes (rubber bulbs), available from your
local drugstore. For fairly thick trailed lines, these bulbs may be used
as-is,
but for finer lines and effects you must come up with a finer tip. The
simplest and most effective solution involves the use of standard
ball-inflating needles, available at any sporting-goods store. Cut off the
very tip of the needle (it has a hole opening to the side, which would be
inappropriate for slip use) and carefully grind the end smooth on a bench
grinder or with a piece of emery paper. Force a small piece of wire or a
nail into the hole to make sure there are no internal burrs. Cut back the
tip of the rubber bulb a little at a time until the broad end of the
inflating needle is a tight fit in the bulb. In use, the tip is easily
cleaned with a fine, stiff wire.
The primary disadvantage of this kind of tip is that it cannot be
dragged against the clay surface, because it digs in badly. To eliminate
this problem, purchase some small-diameter I.V. tubing from a medical supply
house, or have someone in the medical professions get you some. There are
no needles included, so it should not be a problem to get this item. Cut
a 1=22 length of this tubing, and press it about 1/4=22 over the end of the
ball-inflating needle. This will give you a nice flexible tip. As an
alternative, go to an electronics supply store like Radio Shack and purchase
some small heat-shrink-tubing. Place a short length over the end of the
metal tip on the slip-trailing bulb, so that it extends off the tip at least
one inch, and
shrink down the entire length by gentle application of heat above the flame
of a propane lighter.
Gravity slip-trailing produces very even, consistent lines with thinner
slip. An appropriate vessel is a small pinched or thrown egg-shaped vessel,
with a foot so that it will stand up vertically. Cut a half-inch thumb hole
in the upper shoulder, and a spout hole in the opposite shoulder. Glaze-fire
the container, and glue in an appropriate spout at least 1/8=22
I.D., pointing upwards at a 45-degree angle. Fill the slip trailer with
thin, screened slip. Hold your thumb over the large hole, and tilt the
spout downwards. When you remove your thumb, the slip will flow.
Sponges: No, you can't make sponges, but at decorating and building stores
you can buy high-quality poly sponges that work great. They are durable and
last very well, and can be cut with scissors to make custom throwing sponges
and sponge-stamps. Some potters like the thin soft-foam carpet padding -
not the dense hard stuff. A small amount of this gives a lifetime supply.
Sponge Stamps: Random pieces of sponge, or patterned stamps cut from sponge,
can be used to apply colored slips, engobes, oxide washes, or glazes. A
finish similar to that on traditional granite-ware kitchen utensils may be
achieved by using a piece of coarse scrap sponge to dab white slip over
leather-hard dark gray, dark blue, or black slip.
Sponge Stick: Don't waste your time on those ridiculous commercially-made
sponge-sticks with the full-size poly throwing sponge fastened onto the end.
The manufacturer should be ashamed of themselves=21 Just get a length of =
3/8=22
dowel, and fasten a piece of sponge of the desired size to the end with
several wraps of upholstery thread or thin wire, so that the sponge
protrudes off the end of the dowel. Make several sizes for different
applications.
Throwing Stick: When throwing tall narrow forms, such as the neck on a
bottle, it may be advantageous to use a throwing stick. This is just a
straight stick with a slight bulge on one end. It is grasped in one hand
and lowered into the form, and with corresponding normal finger pressure on
the outside, the form is lifted and shaped. Cut the profile from 3/4=22 =
wood,
and sand all the edges round. You can also find tree branches ideally
shaped for throwing sticks. Small throwing sticks for making teapot spouts
and other small tubes can be made with lengths of wooden dowel. Grind a
portion of the shaft to a smaller diameter on the bench grinder, and round
off a ball on the end of the shaft.
Jug Finger (Potter's Finger): When throwing jugs and bottles it is often
advantageous to close in the neck before bringing out the belly or shoulder.
The form can then be resolved with a jug finger, a long straight or curved
stick with a bulbous end, which is inserted through the neck and used to
apply outward pressure against the inside walls. Traditional Early
American jug fingers often just had a wooden bulb on the working end, and
were often made from an appropriate-shaped tree branch. For a simple and
effective jug finger, wrap a chunk of scrap sponge over the end of a
16=22-piece of =BD=22 wooden dowel. Wrap a piece of chamois over the =
sponge, tie
it off tightly with upholstery thread or thin wire, and trim off the
excess chamois - it will look like the drumstick for a kettle drum. In use,
soak the bulb end in your water bucket, and it will be self-lubricating.
After necking in the form, shake off excess water, insert in the neck, and
with the wheel turning apply the necessary outward pressure against the
inside of the form to achieve the desired shape, always with corresponding
finger or sponge pressure against the outside of the form.
For a more elaborate and versatile curved jug finger, trace the desired
profile on a hardwood board, cut it out on a bandsaw, sand all edges smooth,
and make the same kind of sponge/chamois ball on the end.
Trimming Tools: You can easily make band-loop trimming tools, or make
replacement blades for existing tools. Among the best readily-available
blade-stock materials are the flat, thin steel street-sweeper bristles,
often found on city streets. They are extremely durable high-carbon steel,
a superior material for trimming blades, and yet can easily be bent to the
desirable shape. The stainless steel backbone strips found in heavy-duty
windshield wiper blades work well, especially those used in trucks and
buses. Ask for them at truck-stops or city maintenance garages. Another
excellent source of blade material are oil dipsticks from the engine or
automatic transmission of a wrecked car. A visit to a wrecking yard should
get you a lifetime supply for very cheap. Dipsticks are thin, hard springy
steel, but soft enough that they are easily cut and bent to the desired
shape. Bandsaw blades with the teeth ground off work well, but you will
have to heat them with an oxy-acetylene torch in order to bend them.
Whichever source you use, cut 4=22 lengths with wire cutters. Bend =
them
over a rigid round or square form, depending on the shape you want. For
handles, either get wooden file handles from a hardware store, re-use
handles from worn-out trimming tools, or make your own out of wooden dowel,
tree branch, etc., with a 3/16 hole drilled in one end. Press the two ends
of the trimming loop into the hole, just as in the commercially made
trimming tool. If the trimming loop doesn't fit snugly, glue it in place,
or drive in a small metal or wooden plug to lock it in place.
The steel banding often used on shipping pallets can also be used to
make larger band-loop tools, but will require a handle with a larger hole.
Old kitchen knives may be heated and bent to form Japanese-style
trimming tools. Grind off the tip to create the desired straight or angled
end, and sharpen the appropriate edges. Heat the blade in an oxy-acetylene
flame, quickly bend an inch or so of the end at a 90-degree angle, and
immediately quench it in water, before the handle starts to burn. The
heating will remove the temper from the steel, but the quenching should
restore it. The same may be done with heavy commercial bandsaw blades and
reciprocating hacksaw blades. You can also make the same kind of trimming
tool from rigid steel strapping or flat-bar, but it will not hold an edge as
well.
Vince Pitelka
Home - vpitelka=40dekalb.net
615/597-5376
Work - wpitelka=40tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
http://www.craftcenter.tntech.edu/
Kelley Webb Randel on sat 1 apr 00
hey vince,
thank you thank you thank you! i was disappointed about missing nceca, and
your talk was one of the biggest reasons why!
thanks for sharing your handout with us!
be well,
kelley webb randel
rakugddss@worldnet.att.net
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