Jake Green / Katherine Thorsen

Ping Pong Paddles

Concept

<http://www.killerspin.com/stilo7-svr.html>

“...carbon blade for the players who demand high rebound and high speed [1]”

“Weight is relatively low...helps fast attack with hard hitting [1]”

“The blade's hard feel and great speed make it a perfect choice for the fast attacking style of play [2]”

[3]

Mold Material Selection

●Matrix: High Temp Epoxy

○Able to go to 250o F

●Reinforcement: Carbon Fiber Plain Weave

○CTE match

Mold FabricationA clamshell tooling approach was employed to give the paddle two tooled surfaces.

Material Choice● Plain Weave Carbon Fiber Prepreg

○ used on Adidas Accelum High Speed Carbon Paddle

○ lightweight

○ springy

○ available

● Balsa Wood○ used on YinHe T-9 Pro Paddle

○ lightweight

○ available

Lay-Up SequenceFirst Attempt - Clam Shell Tooling

Compression MoldingSecond Attempt - Insert Tooling

Vacuum Bagging / Oven

Lay-Up Sequence

Manufacturing Method

Attempt 1:

● Compression Molding

Attempt 2:

● Vacuum Bagging / Oven

Part Quality●Dry fibers●Handle delamination●Poor surface●Improper resin flow

Testing Method A - Optical Microscopy

Run Incoming Angle Outgoing Angle

1 90 90

2 90 91

3 89 91

4 72 58

5 66 58

6 65 59

7 65 57

8 68 59

Real World vs. Theoretical Calculations

Testing Method B - GoPro High Speed Imaging

BOM

Lessons Learned● Composite tools are better for CTE, but require excellent operators to get a better part than

metal machined on a CNC mill● Leave space to allow for compression of the part● Maximize contact with the platens in compression molding for heat transfer● Two tooled surfaces are possible in ovens/autoclaves● Using subpar prepreg leads to subpar parts● People are crazy about their ping pong paddles

[2][1]

References[1] https://www.megaspin.net/store/default.asp?pid=adidas-accelum-hs-c

[2] https://www.megaspin.net/store/default.asp?pid=b-tamca-ulc

[3] http://www.killerspin.com/stilo7-svr.html