So in our previous video,
we tested the launcher. And we noticed that,
several times, the launcher threw the ball towards
the left, and we wanted to see if we could
straighten that out. So we took a look at some
different key components. You can see those in red. We have our 5/16
stop pin or bolt and our PVC cradle
that holds the ball. Now currently, what happens
is you pull the bar back, and then the ball goes
back with the bar. And then you release
the bar, and the ball travels forward with the bar. And then the bar hits the stop,
but the ball continues on. So what we wanted to
see if we could do is remove the pin
and the cradle. And one of the reasons is
that the pin can potentially be a pinch point, and
it also has the effect of building up stress in a very
specific point on the aluminum bar there. And that stress can work
harden the aluminum. It actually changes the
crystalline structure of the metal over time and
causes it to be more brittle and can eventually
cause it to crack. And so we were going to see if
we could launch the ball using the same kind of technique that
a football kicker would use. So there would be a guy holding
the tip of the ball in place, and the kicker would wind
up and then kick the ball. And instead of the ball
travelling with his foot, he would instantaneously contact
the ball that's being held in a certain point, and
then the ball would release. So we thought it might
be interesting to design a device that could
hold the ball in place, like the guy that holds the
ball in place for a kicker. So we thought maybe we
could take a paper clip and bend it to create a
device, shown in purple here, to hold the ball in place. And then we could remove
the cradle and the stop pin and maybe improve the
accuracy and longevity of wear and maybe even the
safety of the device. So we started with the ball. We put it in its location. Then we took a needle-nose
pliers and a paper clip and started bending
the paper clip to create a larger loop at
the top and a smaller loop at the bottom. The overall paper clip
shape is a C shape when you look at it from
the front of the device. And so it took a little
while to figure out exactly where to
position it, and we drilled a hole in
the side of the wood and put a panhead
wood screw in there to hold the paper clip in place. And then we put a little
loop at the bottom and put another screw
there to just ensure that the paperclip would
be nice and secure. And so once we had the
paper clip in place and it was connected,
we put the ball in and tried to make sure
it was lined up correctly so that the launcher
would hit it. And at this point in time, we
still have the PVC on there. We're still looking at
experimenting with the PVC. We will eventually remove that
because it, with the paper clip, ended up causing the
ball to launch to the side. So we'll do a quick launch
here and just check it out. So we decided to do
some field tests, and we recorded the
distances and the height and the different
angles and positions that we launched the ball at. And we did this a
number of times. We had a little sand
trap set up so we could see exactly where
the ball had landed, and then we recorded
that and tried to figure out if
we could improve the launcher in any other ways. And we noticed that there
were a couple of opportunities for improvement, so we
went back to our drawing and made some adaptations. Finally, we were
looking at our design, and we discovered
that, as we launched at steeper and steeper angles,
like right here, when we're setting the device at steeper
angles-- at 50 and 60 and 70 and 80 degrees-- the top
section of the device tended to fall backwards
or lean backwards. And so when we were
launching the ping-pong ball, it was hard to
reliably launch it without that top part moving. The other thing we
noticed is that we wanted to grab the
launcher to stabilize it, and we tended to want to
grab it right here, which is great except for the
fact that when the aluminum bar swings back, it can
smack your hand on this part right here. So we wanted to make sure
that that wasn't going to be a possibility,
and we wanted to find a way to keep
this top piece down. So what we decided to do was
to create these features. So we have a bolt that we've
cut a little bit short. It goes right here. It's a 5/16 bolt. And we have a nylon sleeve
that goes around it, and that keeps the launching
apparatus or the top piece from coming back or leaning
back when it's at a steep angle. And then we used 1/2-inch
plywood to create a cover for the spring assembly area. And we cut a hole out
in it so you can still access that bolt if you need
to loosen or tighten it, and cut a half a hole here to
do the same with this bolt. But this way, you can
pull the launcher back, and there's no chance of any
kind of being pinched or caught in any way. And so those are the main
innovations on the launcher there. So now I'm going
to spin it around so you can take a look
at it from a number of different angles. You can see there are one, two,
three, four main pieces of wood that hold the cover in place,
and then we have our bolt there with the sleeve. OK, so now we're
going to see what we can do to
improve the launcher and make those changes. You can already see the bolt
with the sleeve is in place there to prevent the launcher
from coming back too far. And now we're going to
measure the top part of the cover that's going to
go over the spring assembly. That'll be 6 and
1/2 inches wide, and then we've got
a 1-inch spade bit that we're going to use to drill
out the holes for the bolts. So that's the center
bolt and the spring bolt. And so now we're just
marking the positions. We're drilling those bolt holes
out and cleaning that off. And we're going to
set our fence up, and that fence will allow
us to use the circular saw to cut a nice straight edge. And we use the
piece of wood there to make sure that
the fence didn't interfere with the clamps. So now we're just trimming
it down to the right length and cleaning off the
edges with a file. And now what we've done is
we're cutting the side pieces. Those are an inch and 3/4
high, and they go all the way around the edge of that box. And we're cleaning
those pieces off. And they're 6 and
1/2 inches wide. Then there's one piece
that's 13 inches wide, and that's the piece that
runs along the long edge. And so now we're just
clamping those in place. We've already marked
them 3/8 of an inch up. We're drilling our holes
with a 1/16-inch drill bit. And now we're just putting inch
and 1/2 panhead wood screws in. And we screwed our
top piece on already, and now we're going to
put the bottom piece on. And just lining that up, using
the clamps to hold it in place, and again, 3/8 of an inch up. And we're just putting
those screws in. Now we're going to go ahead
and put the top part on. And we're, again,
pre-drilling all those holes and using our panhead wood
screws, putting them in. So we have everything lined up. The hole in the center
wasn't as clean as we like, so I'm going to take a Dremel
and go back and clean that hole up, make it a
little bit smoother so that it's sure that we're out
of the way of the bolt below. So I'm going to take
the cover back off, and we're going to assemble
the hardware inside the device again. So you've seen us
do that before, so that's not
anything really new. We're just tightening
down our bolts and making sure
everything is secure. And then we're going
to tighten down all the screws for the
new cover on the launcher and make sure that it works. Now we're shortening
the bolt that we need, which was that little green
bolt that was in the drawing, and cleaning it off with a file. So that's just
going to make sure that the major piece
doesn't fold back when it's at a steep angle, and
so that's the part right there. And there's the original
bolt down below. We've got our paper clip
that holds the ball in place and keeps everything
lined up, and again, we've got our countersunk holes. We can drop the device
completely flat. And I'll just turn it
around here for you so you can see all of
the different components and how it looks
and works together. And we'll set that
angle bolt in, and then we'll put the other
bolt and its sleeve in place. And so now we're
going to test fire it. Put a ping-pong ball in, and
we got a successful launch. So now we're going to
go test it in the field. So we've got our
projectile launcher set up, and we have our numbers
indicating the height on the back in the
black plastic there. And then we have
our tape measure, so we can measure how far
it goes, or our range. Initially, we're going to
set at position 4, which is the fourth position back
from horizontal, and angle 20-- so 20 degrees. And you can see where
the ball lands out there. We went out and
measured it in the sand. The sand lets us see
where the ball landed. So we're at 30 degrees
and the same position-- so the fourth position down. And now we're at
40 degrees-- again, seeing that the ball
is going up higher. Now we're at 50 degrees,
and again, the ball keeps going higher. And the range of the
ball is decreasing, and the height is increasing. And so now we're at 60 degrees. And as we go higher
and higher, the ball tends to veer off a little bit. Now we're at 70
degrees, same position. The ball completely
goes out of the screen, and again, it's not
quite as far away. And now we're at 80 degrees. So we're going to take a look at
precisely measuring exactly how high the ball goes. The sand measures our range,
and we can slow the film down and see that the ball
went just below 3 feet. The top of the paper
is exactly 3 feet, so the ball was about 2 feet 10
inches on that particular shot. So we're going to
try another one. And on that one, again, it
was at 20 degrees, position 4. We can see the ball
goes to about 3 feet 4 inches on that
particular shot. So that allows us
to see the height, and we can use that
in our calculations. Now we're going to see if
we can use this information to knock down a tower of cups. So we've got it all set up. This is position 4, 20 degrees. Yeah. Only three tries.