Bronze Pour Instructions at Pratt

Introduction

This blog contains information regarding the bronze pour activity at Pratt Fine Arts Center. It is intended to serve as a reminder of the pour process. See Pour Day Essentials if you're not responsible for pouring bronze, but have art being cast.

What follows is a mixture of process steps, cautions, and suggestions. And there may be a flow chart in here some where.

Task: Start furnace

The furnace has two intake lines supplying gas and air. At Pratt (picture right), the air is controlled by the Start/Stop buttons that also control the fans blowing into the furnace, and the gas is controlled by a valve (red handled) above the air control panel. The general logic for starting or stopping the furnace is to not have pure gas in the furnace, so air is the first on and last off. When starting the furnace:

1. Turn the Air on - or open air to full. Note that the mix of gas/air is controlled by valves below the on/off panel.
2. Proclaim in loud voice, "Fire in the hole."
3. Then slowly open the gas valve.

Adding too much gas all at once can "explode" out of the furnace opening.

Task: Crucible lift from furnace

1. Tiltman opens furnace door - slides toward deadman
2. Deadman continues opening - do not remove handle from door
3. Deadman and tiltman lift LiftTongs over crucible with lift arms rotated counter clockwise as far as possible so as to clear the furnace door.
4. To lift crucible, tong catch must be off notch.
5. Bring crucible to bricks with winch and align pour spout at center of pour field.
6. Tongs are lift off crucible by hand while still on winch chain - tong catch must be in notch to come free.
7. Hand tongs to WinchMan - who detaches them from chain
8. Close furnace door
9. Get winch hook & fasten to crucible tilt bar - tilt bar hook has an orientation that must be set down correctly before pour.
10. Raise winch until the crucible locks are above lip.
11. Keep tilt bar level at all times.
12. Lock both sides (Deadman & Tiltman)
13. Establish eye contact between all three pourers before lifting crucible from bricks. This is to serve as a safety double check for the team.

Task: Pour

1. "Dead" or "Tilt" commands from the WinchMan indicate which side of the crucible should be moved toward the center of the pour field.
2. Deadman is to stay even in x-axis with TiltMan at all times unless obstacles created by investments or ingot cups require adjustments

Task: Post pour crucible cleanup

1. TiltMan holds crucible at 30-40 degree tilt from horizontal while,
2. Deadman crapes crucible walls.
3. After scraping completed, Tiltman continues tilt to just below horizontal watching that the tongs remain engaged, while
4. Deadman pulls scrappings from crucible.

Task: Return crucible to furnace

1. Return crucible to bricks
2. Remove tiltbar (leave in place)
3. Open furnace door
4. Attach tongs by lifting over crucible, making certain catch is not in notch
5. Place wet cardboard in furnace to create carbon layer between crucible and pedistal
6. Lower crucible with tong arms rotated counter clockwise as far as possible - lower quickly as cardboard may burn before crucible is in place
7. Crucible needn't be centered
8. Lift tongs by hand from furnace - once locked in notch.
9. Close furnace door.