Austin Healey 3000 Alloy Block Project
Pattern Making Process
The images below represent over 1500 hours of work by David Woodhouse in producing pattern equipment for the Austin Healey 3000 alloy block. For those not familiar will foundry principles, a mould (a mixture of sand and resin that sets hard) is produced from the pattern . This mould will be a large block of this hard sand with the shape of the pattern shown below "moulded" into it.. The spigots seen protruding from the shape of the block are "core prints". These core prints are the locators for the "cores" which locate in the prints and form the hollowed out areas such as water galleries and the crankcase space etc. The end result of all this is a large block of hard sand with interlocking blocks of sand (cores), that contain a cavity that is the internal and external shape of the engine block. Into this cavity is poured molten Aluminium alloy.
Right hand side of the pattern for the block, note the extra ribs. Core prints on top, bottom, front and back are the locators for the cores produced from the core boxes shown below.
Left side of the block pattern, with (in foreground) the core box for the cavity in the rear of the block, note the box frame around the core box is the same shape as the block on the right side of the block pattern. The sand block (core) produced from this core box forms the rear of the block casting.
The three core boxes that produce the inside of the crankcase
Left is the core box for the cam follower cavity, right lower is the core box for the standard bore engine, cylinder water jacket. The core box pictured at top is for a 3.8 litre version of the engine.
Note the holes in the side of the core box (bottom left ) match the core prints on the left side of the block. While serving the purpose of locating the cylinder water jacket core, they also become the welsh/core/freeze plug holes in the block.
The pattern mounted into the moulding box along with the runner and ingate system ready to produce a mould.
Home