It's a full-size Play-Doh Fun Factory. The BonL plant was an aluminum extrusion facility housed in a large non-descript building north of Toronto. Thanks to a friend, I was able to photograph the plant in late 2004 — a few months before it closed.
Thanks Donna and John!
In principle, the extrusion process is fairly easy to understand. A material is pressed against an opening. It exits on the other side in the shape of the opening.
With Play Doh that's a fairly easy endeavour. With more solid materials — e.g., aluminum — it's a bit more complex.
The aluminum is pre-heated and pressed (crushed!) against the die. The die is the hole which defines the shape of the extrusion. What emerges on the other side of the hole is the extrusion.
After cooling, the extrusion undergoes a series of finishing treatments. It's stretched, cut to size and hardened with artificial aging ovens.
As for the end result? Machinery, equipment, tuna towers on boats, hinges for glass doors, display cases, refrigeration parts, and the list goes on and on.
The extrusion process generally creates parts that are used in the assembly of larger items. You'll find extruded aluminum pieces in everything from golf carts to heatsinks to televisions.