1. Staring “The Bridgeport Mill”
Child’s Toy Maze
Staring
“The Bridgeport Mill”

2. The Maze Each student will be creating a child’s toy maze using..
4x6x.5 Acrylic Plastic Base
4x6x Acrylic Plastic Cover
One BB
This is a 5 step Project
Analysist of a BB
Milling Machine Safety and operations
Design
Manufacturing
Final Assembly

3. Analysis of a BB Students will do the predesign work.
Determine BB size
Size of the Groves
Determine cutter
Calculations
Explain in this slide that student will calculate the mean of the BB
Then using that will determine how wide and deep the groves must be.
Based on groove size, this will determine the size of the cutter. Remember to let them know that the grove must be bigger then the BB so they have to choose a cutter larger then the BB. I have always used a 3/16 Ball endmill. But the project would work equaly as well with a ¼ Endmill
Also hint that the shape of the cutter is also a factor. Endmill ( Flat) Ball endmill, face mill, or drill also is part of the cutter decision.
Lastly, after the cutter is chosen, they will calculate the proper speed of the cutter, given the restriction of cutter material, size and material to be machined.

4. Safety
Before working with any new machine in the Machine Shop students must…
Learn Machine Safety
Understand It’s operations
Students will take a 3 part safety lesson
Safety Worksheet –must be filled out by student then have the instructor sign it off
Safety Test- Student must take and pass with 100% the safety test, student can take the test as many times as they need for 100%
Safety/ Operation Demo and/or a video.

5. Design Students will design a toy maze and draw it on grid paper
It must contain a minimum of 20 segments.
No two parallel segments can be within .1 of each other
Student must produce two copies of their maze design
(Copy, Scan, Photo)

6. Machining Using a Vertical Milling Machine, Student will layout design
Students will setup the mill
Machine the part
Breaking down
Cleaning up
Vertical Milling Machine also known as a Mill, Bridgeport, or Manual Mill
Layout means to cut out and glue one copy of their design on the protective paper that is attached to the plastic.
Set up includes, loading part in Vice, selecting and installing proper tool.
Machining the part includes setting the depth controls as well as moving the handles to follow their design. It is understood that this is their first mill project, so some error’s will result The goal is to see improvement from segment 1 to segment 20.
Break down and remove the cutter and the material
Cleaning up, is getting the machine clean of chip, whip down metal surface, general cleaning.

7. Final Assembly Check that the BB roles in all the segments.
Place a top and check that the groves are deep enough
Clear all groves of debris
Attach the top
Finish Saw cut edges
While grove is wide enough, often depth and chips get stuck in the groves.
2. Students often do not secure the clamp on the quill, so often you get ramming in some of the groves.
3. If gluing the top on, make sure the BB is as fair for the glue as possible.
4. Finish saw cuts is sanding, to 220 grid, polishing on buffer then flaming over a propane troch. ( this is optional )