Refining Plaster Prototype

Altering turned shape made on the plaster lethe; trying multitude of tools.


20161202_171040
As my intention to create 4 different feet as a base for the cup, inspired by the 4 legs of the Penguin Donkey couldn’t be realised through the lathe turning stage, I had to work onto the turned form further, and carve the feet away.

Drawing a technical sketch of the base in my sketchbook, and carefully calculating the legs’ positions, I could place my turned form onto it to accurately mark the legs’ positions.

I started carving away bigger chunks with range of small hoop or cutting tools. However, that proved too brutal and I was scared I would accidentally damage the prototype.
Therefore, I went to small metals workshop and used Dremel tool to precisely carve the feet away with much more control in my hands.

This proved as a great, precise and fast way to alter a prototype. Using multitude of attachments and different speed settings I could carve away bigger chunks, take small quantity of plaster closer to the feet and get into the more awkward angles, 20161203_125357as well as smooth the surface level.

To smooth all the edges precisely, I had to switch to using wet-and-dry sand paper of various grades, to safely file away the small quantities of plaster.


I again rather enjoyed doing small, precise and planned manual alteration of form.

However, I’m not entirely happy with the prototype. I feel the legs and bottom curve should be even more pronounced, to better represent the original Penguin Donkey and its long feet and profound curves. I’m afraid the shrinkage of the clay after glaze firing will make the features rather insignificant.

At the end, it is only a test piece to challenge my skills further. I hope I’ll be able to
produce even better and more prototypes with more confidence20161203_131240.

Tea for Two – Progress/Process

Progress of the 4 weeks, working on the Tea for Two project, illustrated through photographs.


 

Stitching number of pieces of fabric to create moulds for the parts of tea set.
Tea for 2
Filling the fabric moulds with plaster to create number of plaster prototypes.
These then can be used to create plaster moulds for casting with slip.Tea for 2

 

 

 

More plaster shapes and components.Tea for 2

 

 

 

 

 

Plaster saucers.

Tea for 2

 

Used fabric moulds dipped in black slip and fired.
This method is actually much faster and simpler than making plaster moulds, with better, undisturbed detail. More experimental shapes are possible, just less functional.
Tea for 2

 

Slip-casted and fired cups.Tea for 2

 

Fired slipware, some of them glazed, with oxide wash and transparent glaze, or other.
Tea for 2 Tea for 2

Tea for Two – Plaster workshop

Working continuously for over a week in the plaster room to create plaster prototypes from my textile stitched cups and then plaster moulds for slipware.


Textile cupAs I wanted to explore the holding and containing abilities of a tea set, and possible absence of it, I looked at shape created by the act of accommodating.
I chose textiles and stitch as it’s another object associated with home and domestic environment. Available at my house too, I spend few late evenings cutting shapes and stitching them together to govern the final shape to some extend, to at least appear like a cup or a teapot.
Textile mould

Tea for 2

 

 

 

 

 

 

 

 

Supporting form while plaster hardens

 

 

 

Filled with plaster, even thought the textiles forms were assembled from number of parts to hold the shape, the plaster was much heavier and overpowered the stitches.
In some cases I had to hold the shape until the plaster hardened, or supported them with boards, strings or in a container.

Teacups from 1 textile mould Teacups from 1 textile mould

At the end I ended up with fairly large amounts of prototypes, as the teacup moulds were open, allowing me to separate the plaster and textile without the need of ripping it, as necessary with other textile moulds. I was free to experiment with the way they stand and fold, turning them inside out, bounding them with string, etc.

Teapot spout?

Attempting for a smaller components such as spouts and handles, which are trickier.
The only worry is how much they will shrink in the kiln as a slip cast, and being able to pour.
Plaster mould
The hardest and most time consuming part was creating the 3 plaster moulds for slip casting.
With highly irregular shape, I had to look for many undercuts and divide the shape into 4 to 8 part moulds.

However, taking every opportunity to work in the plaster room, I managed to produce the 3 fairly complicated moulds in about a week + extra day or two; getting essential skills at more detailed plaster mould making. Of course through many mistakes too.

Progress on throwing & turning skills

Throwing on and off for about 2 years, I really want to extend and perfect my skills in throwing and turning vessels in this first year project.


throwing with 1kg ball of cal

These are my latest trials in throwing with a larger, 1kg ball of clay of White St Thomas.

By this point, I found centring and pulling up the walls relatively easy, as well as centring and turning leather hard vessels.
Being so scared turning my pots before and always thinking how impossibly hard it is; by now I must say I am looking forward to turn every single vessel I throw on the wheel.
However, there was significant collapsing and failing when adapting the shape of a larger cylinder, showing me that I need plenty more practice.


trying to throw identical cups
That was after setting a small challenge of producing number of identical cups
from 400g of Ash White. Drawing the design and then using a ruler to measure the width and hight while throwing, I managed to produce 9 reasonably same cups.

 

turningturning
This exercise was great to limit myself into a one, slightly inward curved shape, and repeat it over and over; focusing my skill to develop in areas important when throwing: controlling the hight, width, thickness of the walls, curvature, etc.

However, I still feel that I don’t have full control in ensuring the shape and size is identical, therefore I shall repeat this challenge again to be more consistent in my work.

I also turned each cup to finally learn it, therefore the result was always slightly different, not really limiting myself but rather just play and get practice in the pure timing of the leather hard stage and centring and not cutting through the walls or bases.



extruded handle
I pulled handlealso tried to apply handles onto the cups. First pulling a handle, which proved to be rather tricky, but after a few attempts the result was acceptable.

Extrusion
Nevertheless, I wasn’t completely satisfied with the result; so I touched the extruder for the first time.
The result was even less satisfying, with the extruder disk providing too thick handles for my cups.
However, the immediacy and industrial, like a pipe or cable look was desirable, so I’ll have to look at producing my own extruder plates later.

Here are my earliest thrown object from 500g balls of Ash White and Terracotta at the beginning of this year. Always going for as thin and light walls as possible, but still rather modern, industrial and rather minimalistic look.

In the very near future I have to look more on functionality of my vessels. In their shapes as well as features such as handles, spouts and lids.
earlier throwing practice earlier throwing pieces