Introduction: Baseball Soft Toss Machine
A baseball, two pound weight, and a wooden plank were used for my first prototype. I conducted a test run of my prototype through creating a simple design with a first class lever, where I put a wooden plaque on a two pound weight, which served as the fulcrum. I then put a baseball at the end, which served as the load, while my foot serving as the effort, when I stepped on the wood from the other end.
After performing a few trials with this lever, I thought about the design of this project, and decided that its performance could be improved by using a longer metal pole for more mechanical leverage, with a hand scoop at the end to hold the baseball. Ultimately, I used springs to help put more force into the mechanism to get the baseball to the height that I wanted.
1 - Steel perforated square tube (3 feet)
1 - Steel round tube (3 feet)
1 - Hand scoop 2 - U-bolts (1.5 inches wide)
2 - ⅜ inch threaded rod (3 feet)
1 - 3/16 threaded eye bolt (3 inches)
1 - poplar project board 2 - 2x4 lumber (3 feet)
1 - box of ⅜ inch washers
1 - box of ⅜ inch nuts
2 - ⅜ inch metal bolts (3 inch)
1 - bag of utility springs (various lengths)
1 - bag of ⅛ inch quick links
2 - rubber grommets (¾ inch inner diameter)
1 - plastic lid
Start by screwing the eyebolt in the center hole of the steel square tube. Use nuts and tighten so the opening of the eyebolt is parallel to the square tube. It is important to note that nuts should be used at both the top and bottom of the steel tube in order to ensure that they would both tighten with the wrench. Slide the steel round tube through the eyebolt opening and use the two rubber grommets to keep the tube in place. The longer end of the tube is where the hand scoop will be attached.
Connect the hand scoop to the end of the round tube so it is parallel to the tube using the two u-bolts. Use a wrench to tighten so the hand scoop is securely attached to the tube. This is where the baseball will be placed. Cut the plastic lid to the shape of the end of the hand shovel and hot glue it in place. This will hold the baseball in place while it being tossed.
Secure the ends of the square metal tube to two pieces of wood to create a stable platform. First drill holes into the wood so the bolts to go through using a drill bit that is slightly larger than the bolt diameter. Also cut around the hole at the bottom so the top of the bolt will go into the wood, to keep the base stable. Use the two bolts and attach washer and nuts, and tighten with a wrench.
Using a large drill bit, drill a whole into the project board with a diameter of ¾ of an inch. This is where the other end of the round metal tube will go into to create a lever mechanism. Cut the board so the height of the board is long enough so that the other end of the tube is on the ground.
Now that the lever mechanism and the base of the system has been built, it is time to build the spring system to provide the energy to toss the baseball. Use two nuts and two washers to secure the end of one of the threaded rods to the square tube, close to wood base. Do the same on the other side. Also use two nuts and washers with a quick link in between to provide a hook for the springs. Repeat on the other threaded rod. Also use one nut, one washer and one quick link on each side of the first u-bolt on the handle scoop. This is used to attach the other side of the spring.
Experiment with different springs to get the right amount of force to toss the baseball to the right hitting height. FInally use any type of weights on the end of the wood base to make sure the mechanism doesn’t lift up when using. Finally, put the trigger in place with the springs extended, place the baseball in the scoop, get your bat and trip the trigger with your front foot and hit a homerun!