Round Disks
(disks are actual size; number in center are number of disks / sheet)
32
Diameter = 2.9"
15
Diameter = 4"
28
Diameter = 3.0"
18
24
Diameter = 3¼"
Diameter = 3½"
Octagons
(disks are actual size; number in center are number of disks / sheet;
octagons (& other shapes) have a short and long dimension)
3.03
in
n
i
0
3.9
32
18
2.81 in
3.35
in
3.60 in
n
i
4
6
.
3
28
20
3.10 in
Note: a disk 3¼” wide
will yield 26 disks / sheet.
3.37 in
Rounded Triangles
(disks are actual size; number in center are number of disks / sheet)
3.84 in
3.96 in
18
26
2.79 in
38
2.70 in
28
3.26 in
3.16 in
2.95 in
3.05 in
Various Other Requested Shapes
(disks are actual size; number in center are number of disks / sheet;
again, these can be made any shape on acrylic plastic)
24
2.8" x 3.8"
Oval
18
3¾” square
w/ rounded vertices
Octagon
Smooth Vertices
28
Heptagon-pointed
3.1" x 3.1"
28
Hexagon
Vertical: 2.8"
Horizontal: 3.25
21
28
3¼” square w/
rounded vertices
Heptagon-pointed
~3" x 3"
Other Options…
(disks are actual size; number in center are number of disks / sheet;
again, I can cut any shape or size on acrylic plastic)
24
24
Icosahenagon
Medallion-pointed
21 sides; 3¼” diameter
Icosahenagon
Medallion-smooth
21 sides; 3¼”
24
Star-pointed
5 points; 3¼”
24
Triacontatrigon
Medallion-pointed
32 sides; 3¼” diameter
24
Star-smooth
5 points; 3¼”
~28
Pentagon (pointed)
3¼”
Common examples of graphics engraved on both sides of disks.
S ASSOCI
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2012
Richard Gebhart
Reno Nevada
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Number of disks per sheet & cost calculation examples
I cut disks from stock that is 12" x 24. If you want 96 round disks that are 3¼" in diameter, I would
need to cut these from 4 sheets of acrylic plastic (96 disks ÷ 24 disks per sheet = 4 sheets). If I reduce the
disk diameter by ⅓" the disks would be 2.9," I can get 32 disks per sheet of acrylic. Thus, I would cut these
from 3 sheets (96 disks ÷ 32 disks per sheets = 3 acrylic sheets).
Engraving also affects cost per disk. If you want engraving on both sides of the flip disk, a sheet of
acrylic disks costs $70 / sheet. If you want 2.9" round disks, I would use 3 sheets, so the cost per disk would
be $2.19 (3 x $70 = $210; $210 ÷ 96 disks = $2.19 / disk). If you want 3¼" round disks, I would use 4 sheets,
so the cost per disk would be $2.92 (4 x $70 = $280; $280 ÷ 96 disks = $2.92 / disk).
Use this calculation logic regardless of what shape disk you request. The shapes and sizes in the
previous pages give you an idea how a small size difference can affect your overall price. I can cut any
shape and size you want from plastic or laminate. For other shapes, I will calculate how many disks I can
get on a sheet of acrylic. Calculate your overall price based on how many disks I can fit on a sheet and how
many disks you want. I round up to the nearest half sheet. If I calculate you need 3.3 sheets for your order,
I will charge you for 3½ sheets; if you need 3.65 sheets, I will charge you for 4 sheets. You keep any
“overages” except I generally keep one disk (if I use more than two sheets on your order) so I can show
others and have a template if / when you want more disks.
And now a word about flipping disks…
Many believe that only round disks roll on the mat. Fact is, ALL disks will roll when they hit the mat just
right. While round disks can / will roll farther than a disk with a non-round polygon shape, all disks will still
roll, with very few exceptions. It is better to work on preventing a rolling situation from happening,
regardless of a flip disk’s shape. The key is to flip the disk fast, i.e., provide sufficient kinetic energy, so that
the angular rotational momentum is great enough to cause an “uneven” flip disk landing and preclude
rolling conditions from being met: the faster the flipped disk spins, the less likely generated potential
energy will “allow” a disk to land on its edge and roll. In order to roll, a disk has to land slightly off vertical
(the Y axis), which allows a direction to roll, but not so far off (the Z) axis to create a wobble, which would
quickly limit any rolling energy. A slower flipping rotation will allow more temporal opportunity for
potential rolling conditions to be met. Symmetrical polygons shapes, such as octagons (8 sides) (or
hexagons, 6 sides), will roll more frequently and farther than non-symmetrical disks, such as pentagons (5
sides) or heptagons (7 sides), etc. When a non-symmetrical disk rolls, its uneven polygon shape will cause
the disk to be more off balance as it rolls (Y axis), so it would loose directional momentum more quickly and
fall over. “Rounding” vertices of polygons can also increase the rolling distance, compared to its obtuse
angled parent shape. OR, you can catch the disk in the air (& not expend energy bending over to pick it up)!