To:		Manufacturing Design Teams
Date:		2006-03-28
From:		Ralph Stirling
Subject:	Puzzle piece manufacturing system specifications

Summary

The 2006 model burr puzzle piece production system must meet specific criteria for entry and exit of blocks, part quality, dust collection, and safety.

Criteria

1.	Raw material: hardwood blocks (species including walnut, maple, cherry, and possibly others) of nominal dimension 0.75 x 0.75 x 2.25 inch, +/- 0.003 (95%)

2.	Machine must cut zero, one, two, three, or four notches 0.375 inches in width and depth on one face of each block, and zero, one, or two notches on the second face, according to a standard digital coding scheme to be specified by week 4.  Notch position, width, and depth must be accurate enough that 95% of puzzles assembled with the blocks manufactured by the machine can be assembled with no more than 2 pounds of force on any block.  Blocks should be interchangeable between different puzzles (of the same design).  Pay special attention to eliminating the need for any secondary operations, such as shaving off “feathers” or sanding.

3.	Blocks are to enter and exit the machine by belt conveyor, traveling in the long direction.

4.	The machine is to be designed such that the overhead 4 inch dust collection port will efficiently extract the wood dust and shavings from the cutting operation.

5.	The machine is to be designed such that jams are minimized and that clearing a jam is a safe and easy operation.

6.	Design noise-reduction measures into your machine.  The current machine produces a noise level of 89dBA with the router running and 93dBA while cutting, at a 1 meter distance.  My target goal is no more than 72dBA at 1 meter.

Please study these criteria in preparation for team meetings at lab time Tuesday April 4.  Come with well-thought-out ideas on slot cutting machine architecture.

Observations you might wish to make:

1.	How long does it take to produce six blocks?

2.	Are there any obvious ways to improve the production time?

3.	What are the likely places for jams to occur?

4.	What defects do you observe in the blocks?

5.	How easy or hard is it to align the machine (initially and when changing router bits)?

East Machine		West Machine			South Machine