Maze Laboratory

Design and machine a maze that uses either a 1/8” or 3/16” ball bearing. See previous examples of work found in the Manufacturing Center.

The part will be graded on the following criteria:

· Timeliness: completed by due date. (Mid-Term)

· Each student in the group will fabricate a part. All members of the lab group should assist.

· Machining surfaces: neat and clean, no witness marks, no sanding or scotch-brite. The machining marks must be left on the part.

· Part thickness and consistency of thickness as well as finish and machine marks. I’ll specifically be looking for chatter.

· The cover should be fabricated using 0.060” thick polycarbonate, and have an interference fit. All exposed edges should be deburred.

ProtoTRAK Mill: cutting speeds, feed rates and depth of cut table

Tool #	Description	Cutting Speed (V) sfpm	Feed Rate In/tooth	Depth of Cut (DOC) inches
1	2.25” face mill	700	0.003	0.050”
2	½”” end mill	200	0.004	20% Æ (0.1”)
3	¼” end mill (3 flute)	170	0.002	30% Æ (0.075)
4	3/16” end mill	100	0.003	40% Æ (0.075”)
5	Chamfer engraving tool	150 150	0.002 0.002	length0.015” - clear0.025” 0.0015” max DOC
6	spot drill	100	0.004	0.03” DOC
7	3/16” drill	100	0.004	0.1” variable peck
8	½” drill	200	0.004	0.15” variable peck
9	1/8” ball mill WAX ONLY	2500 rpm	40in/min	2.5% stepover

NOTE: Before cutting the remaining ¼” stock off the back side of the part be sure to use the band saw to cut as close as possible to the part. This will minimize the overhang on the part. The lab will be a lot quieter on the final passes of the part.

Be sure to track each tool to part height 0.0 before hitting go. Please use a touch of cutting fluid for each operation. It makes cleanup a bit more difficult, but you get a better cut.

Always calculate your spacer height before starting.