Test Your Fate: Spring Issues / Ball Tests

In order to finish the production of the pinball machine the plunger needed to be fitted before adding the perspex to finish the machine. However a few issues arose as it was difficult to sources a spring that would be powerful enough to shoot the ball up the board and big enough to fit on the dowling. Initially the spring's sourced either fit the dowling but was not powerful enough to move the ball or seemed powerful enough but where slightly too small for the dowling (see figures 1-4). Therefore I tried stretching the sprint using tools in metal work however it was very difficult to fit the dowling and once on had lost its power due to being stretched (see figure 3).  Therefore more springs were ordered to see if they would fit the diameter of the dowling (12mm). This was difficult as the website selling the springs had limited descriptions therefore I only knew exactly how big each spring (see figures 5-6). Springs with higher tension and more coils were ordered as the higher the tension the more powerful, meaning if they needed to be stretched there was a greater chance the spring would still be powerful enough. Out of the springs ordered two were potentially usable but not the correct diameter, therefore stretch was attempted again. However due to the high tension within the spring this was too difficult, as not the whole spring would stretch only sections (see figure 4). Therefore I decided to remove the original dowling from the plunger and use a thinner piece that would fit the spear spring perfectly. As the hole in the plunger block as fit for 12mm dowling epoxy resin was used to secure the thinner piece so avoid recreating the whole plunger again. Once this had dried the spring was tested however the spring was too powerful and the plunger would travel up the board too. Therefore a buffer spring was fixed to the outside of the pinball machine to limited the back coil once the plunger was released (see figure 7).

Furthermore multiple balls were tested to see which would work best within the machine. Initially ping-pong balls were used however due to there light nature and bounciness they tended to not fall into the holes. Therefore traditional pinballs where purchased (see figure 6) however these were very heavy and smaller than expected so tended to get stuck between obstacles at the top of the board. Therefore bouncy balls were tested as they act in a similar way to ping-pong balls but are a bit heavier. They worked very well, bouncing off the obstacles and flippers whilst still falling down the holes.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7