Fidget Spinner
1.
Introduction
5.
Assembly
This
document is intended to explain the manufacturing sequence for a Fidget Spinner
Important
Notes [RETURN TO TOP]
1.
Material Selection: Use
the square plates in the cardboard boxes behind the lathes for the Fidget
Spinner body
2.
This part requires many advanced operations
on various machines. If you do
not have advanced training on any operation, consult Mike or an older TA for
help
3.
Make sure to check tool center
height EVERYTIME you change tools. Failing to do this will result in broken
tooling.
Fidget
Spinner Body [RETURN TO TOP]
1.
If the stock
is large enough to manufacture 2 spinner bodies from, cut it in half on the
bandsaw, and place the drop stock back into the cardboard box
2.
Use calipers
to measure the width of each stock to ensure the sides are parallel and able to
be clamped on
a.
If
the stock is not parallel (ends within 0.003” of one another), take light
depths of cut on either side to make lengths parallel
3.
Face and
finish each side of stock so that the thickness is between 0.275”-0.280”
4.
Use the
cylindrical edge finder and the centerline function on the DRO to zero/find the
center of the spinner on both the X & Y axes
5.
Use the ¾”
annular cutter (~700 rpm) to remove bulk material from the 7 hole locations (4
internal, 3 external)
6.
Load a
27/32” drill (~250 rpm) and drill out all 7 hole locations
7.
Use the
boring head on the milling machine to finish the 7 holes (500 rpm-600rpm)
a. CAUTION: Do not attempt to do this
without Mike or an experienced TA. This is a VERY dangerous tool and the
process is not trivial.
b.
Finish the 3
external holes first to dial in the boring head for hitting the hole tolerance.
Remove 0.022” on the diameter (roughly 0.011” radial depth of cut), and a
spring pass. Use internal micrometers to measure
c.
Finish the
remaining three internal holes (not the center hole), to within the tolerance
(0.8655-0.8660”). This is the last chance to make any adjustments to the boring
head before the center bearing hole is finished.
d.
Use the
boring head to finish the last hole (center hole). If the hole is out of the
tolerance range (0.8655-0.8660”), the bearing will not press fit in, and you
will need to start over J
8.
Print a 1:1
scale drawing of the spinner body, align it with the holes on the spinner, and
glue it to the body
a.
NOTE: ensure
you double check the printed drawing is truly 1:1
9.
Change the
blade on the Do-All bandsaw to the blade marked for the spinner
a. Ask
Mike or a senior TA for assistance in changing the bandsaw blade
10. Use the Do-All bandsaw to remove large chunks
of material, but ensure enough room is left between the edges of the spinner
for finishing
11. Take the spinner to the sander, and adjust
the speed (~30), and create the contours of the spinner. It may be easier to
remove the 1:1 drawing, and use your eye to even out the edges
a.
Ensure you
are dunking the spinner in water to ensure the part does not get too hot
12. Clamp the spinner in vice, and use array of
files to create curved/chamfered/preferred outer profile
a.
Either use
the brass jaws in the welding shop, or ensure you are not clamping on the piece
too hard with the hardened steel jaws, as you do not want to deform your
material.
13. Polish aluminum body
Fidget
Spinner Inserts [RETURN TO TOP]
1.
Measure the
three internal holes (excluding the center hole) of the spinner body with
micrometers, and record the hole size of each hole
a.
If the holes
are not within the tolerance (0.8655-0.866”), ensure you record the measurement
of that hole, so you can alter the size of the brass inserts
2.
Select the
1” diameter brass round stock for the spinner inserts
3.
Load the
brass into the lathe and take a finishing facing pass. Load the stock close to
the chuck to maximize rigidity, but ensure to leave enough clearance between
the chuck jaws to turn/part off.
4.
Turn the OD
to 0.8660-0.8665” on the diameter, to a Z depth of 0.400”
a.
If you
spinner body holes were not in tolerance, turn down the brass inserts so they
will have an interference fit of +0.0000-0.0005 with the spinner body
b.
Measure the
external surface with micrometers to ensure you hit the required tolerances
5.
File the
insert while still clamped in the chuck
6.
Drill center
hole using 0.250” and 0.297” drill
7.
Finish
center hole with 0.3125” reamer
8.
Use 110°
countersink tool to depth of 0.100” after zeroing the cutting edge of the countersink
tool on the edge of the hole
9.
Use the
part-off tool to part off the insert.
a.
Load the
part off tool such that part of the tool is in contact with the larger
diameter, and part of it will come into contact with the smaller diameter
10. Load the parted-off workpiece into the chuck
jaws.
a. CAUTION: Do not clamp the part too tightly, as the
brass insert may easily deform
b. CAUTION: As the insert will be small, you must ensure
the part is clamped correctly. Turn the spindle down all the way, and ensure the
part is not spinning off center
11. Face workpiece so the final thickness is
0.270-0.275”
12. Drill counter sink into the other side using
same method as step 8
13. File the other side of the insert
14. Repeat the above steps 2 additional times.
15. Polish brass inserts
1.
Use the vice
to press fit the brass inserts into the spinner body
2.
Use the vice
and sockets (to mitigate Hertzian contact stress) to
press fit the bearing into the center hole
3.
File/sand the
spinner if needed