Step 1 - Fabricating the Base Plate Pattern.

The BASE PLATE is an irregular shape that is based on a rectangular footprint measuring 5 3/8"x 11 1/2" and 1/2" thick.  On top of the base plate is the angular pad to which is fastened the rubber sweep.  On the bottom of the pad are two rows of reinforcing ribs and a 3/4" mounting block which fastens the casting to the motor car.

The wooden pattern for the base plate is made from 1/2" Baltic birch.  Using the table saw, cut a rectangular piece of 1/2" Baltic Birch measuring 5 3/8"x 11 1/2". 

Using the existing aluminum casting, trace the pattern of the base plate onto a piece of stiff card stock.  Retrace the lines on the card stock using a straight edge to make sure that all straight lines are parallel.  Make a copy of the drawing and add the key measurements to the copy.

An additional pad will have to be included in the base plate underneath the upper part of the wing.  This pad will serve as a platform to mount the core prints. The base plate pattern should look like this. 

Cut out the copy of the card stock, leaving all lines in.

The base pattern is cut out of the birch plywood using the band saw.  Use the band saw fence to make sure that straight lines are cut.  Free-hand cut the inside curves.  DO NOT CUT THE OUTSIDE CURVES!  These will be cut after the ribs and mounting block have been glued and fastened to the base plate.

Sand the inside curves to produce a smooth finish.