Baseball Device for Batting Practice - a 30-foot pendulum
Early in 2004, I created an interesting device to enable kids to
(1) get exercise; (2) have fun; and (3) improve their baseball hitting
skills. The neighborhood kids included the three girls shown in these
movies. Megan (in red shirt) was 7 and Terri (in pink) was 8. Both of them
had only hit T-ball before that day, the method where the softball is
placed on top of a column so the kids can hit a non-moving ball. Terri
is amazing in doing such things, as she has only ever had one arm.
Marissa (in blue) was 9, and had hit a pitched softball, but she had never
had interest in softball because she was not very good, mostly hacking at
the ball. However, their father had certainly taught them how to
hold the bat high while waiting for a pitch!
I took a standard 12" softball and drilled a 5/16" diameter
hole through the center of it. I then bought a roll of 100 feet of
1/4" yellow polypropylene plastic rope (for a few dollars) and
used some adhesive to stiffen up around 6" of the end of it, which
I used as a needle to get the rope to go through the hole in the ball.
I then cut off the needle part and tied three half hitch knots in
the rope (to make sure the ball could never come loose!).
Over the street next to my house is a strong horizontal branch of a large
tree. The branch is around 27 feet above the ground. I threw a
different softball over that branch, through which I had drilled a hole
and put a kite string (fishing line is equally fine). The lighter
string did not affect the direction the ball flew when I threw
it as much as it would with the heavier rope. I then used the string
line to pull the poly rope up over the branch.
This resulted in the softball hanging on the rope from the rope
over that large branch. The rest of the rope had gone over the
branch and came back down, where I tied a steel washer to it at a
point where it would be several feet above the ground at the trunk
of the tree (toward the right in the photo and movie). I drove several
nails (temporarily) in the tree. By hooking the washer around a
specific nail, the baseball could then be a selected height above
the ground. I placed the nails so that I could have the ball about
at knee-height (the lowest pitch which is a strike) and each 6"
higher up to armpit height (the highest pitch which is a strike).
Therefore, adjustment of the height of the pitches is simple and
easy to do. There are no other variables to consider!
Since these girls had only done the stationary T-ball before,
I suggested to them to first have the ball standing stationary,
but hanging from above rather than being supported from below.
After a few swings each, they were solidly hitting the ball.
The oldest girl, Marissa, was severely chopping downward at the
ball, which was very obvious and a brief suggestion solved that.
Within 5 minutes of them starting with this device, there was massive
improvement in all three. It also was immensely popular, as they had
great fun with it! Every day afterward, there were knocks on my
door where they asked to use it again!
Since these girls had never really had much interest in softball
before, none of them had an aluminum softball bat. Therefore,
they had a great additional complication in these first-day
movies in having to use my adult oak baseball bat which is very
heavy. The smallest of the girls often went all the way around
when she swung due to the heavy bat! ALL of them wanted to
WAIL on the ball, and they often did, and loved it!
The 27 foot height of the branch caused even ME to try really hard to
put so much smoke on the ball to try to get it to go so high as to come
down OVER the branch. I could certainly cause the ball to regularly go
much higher than the branch, and it sometimes came close to coming down
over the branch, but I never accomplished it. A relative of a neighbor
came by, having played in AA baseball (very high level play) and he
certainly also came very close to having the ball go over the branch,
and he certainly tried many dozens of times, but he never did either.
We each got a couple hits where the ball came down and HIT the branch
but then bounced short! That probably was just as well, because if either
of us had gotten the ball to go over, then the rope would no longer
be over the branch and I would have to re-load it! He agreed
that this practice device is an extremely useful training device,
and it provides many challenges to any level of player. He said
that it would have been great during the first week of Spring
Training, where hitters could practice hitting knee-high pitches
and numbers-high pitches and everywhere between, where there is a
randomness of where the ball will be to hit. And the fact that
there is such an obvious and immediate display of how well you hit the
ball, it is wonderful feedback! He thought that all PRO teams
should make one of these things, and so certainly Colleges and High
Schools should certainly make themselves one to use!
This presentation was first placed on the Internet in November 2007.
The movies shown were taken in April 2005, and it was invented
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C Johnson, Theoretical Physicist, Physics Degree from Univ of Chicago