ART
BEAUTY & WELLNESS
CRAFT
CULTURE & HISTORY
ENTERTAINMENT
ENVIRONMENT
FOOD & DRINKS
REVERSE ENGINEERING
SCIENCES
SPORTS
TECHNOLOGY
WEARABLES
Plumbago Crucibles: Fire Clay, Coke and Graphite, Ure 1839
Crucibles must stand sudden heating and cooling without cracking. Andrew Ure (1839) gives the best as pure fire clay with ground old crucibles, black lead (graphite) and some coke: a Berlin mix of 8 parts clay and cement, 5 of coke and 4 of graphite stood 23 meltings of 76 lb of iron each. Mix it like a pottery body, press it into crucibles, dry them slowly and fire them.
The picture: used graphite crucibles.
Advanced
A week with drying
Instructions
1
1
Grind and sift
Grind and sift
Pound the coke and the plumbago fine and sift them; sift the grog.
Materials for this step:
Metallurgical Coke1 kg
Plumbago (Natural Graphite)1 kg
Grog (Crushed Fired Pottery)0.5 kgTools needed:
Mortar and Pestle
Fine Mesh Sieve
Dust Mask2
2
Mix the body
Mix the body
Measure by bulk 8 parts fire clay with grog, 5 parts coke and 4 parts graphite (Ure's Berlin mix). Mix dry, then add water and knead to a stiff dough as for pottery.
Materials for this step:
Refractory Clay2 kg
Water1 literTools needed:
Balance Scale
Bucket3
3
Form the crucibles
Form the crucibles
Press the dough hard into a mould round a wooden former, or over a tapered former, keeping the walls even and not too thick; ease each crucible off and trim the rim.
Tools needed:
Wooden Mallet
Utility Knife4
4
Dry slowly
Dry slowly
Dry them slowly in a warm room for several days, turning them now and then, until no moisture is left.
Tools needed:
Drying Rack5
5
Fire
Fire
Bake them in the kiln, raising the heat slowly. Store them dry and warm each before first use.
Tools needed:
High-fire Kiln6
6
Ure's Berlin mix
Ure's Berlin mix
Loading Jupyter Notebook...
Materials
5- Placeholder
- Placeholder
- Placeholder
- 2 kgPlaceholder
- 1 literPlaceholder
Tools Required
9- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
- Placeholder
This blueprint makes
Related Blueprints
These blueprints share knowledge with this one — techniques, materials, or principles that connect them in the learning graph.
CC0 Public Domain
This blueprint is released under CC0. You are free to copy, modify, distribute, and use this work for any purpose, without asking permission.
Support the Maker by purchasing products through their Blueprint where they earn a Maker Commission set by Vendors, or create a new iteration of this Blueprint and include it as a connection in your own Blueprint to share revenue.