Building
All parts that needed to be machined were done so in the machine shop in room 98C on NAU's campus. Many of the parts were machined by hand by one of the teammates, but some of the more complicated pieces were completed by the machine shop personnel. Work orders were submitted in February and they finished all our order by March 31st.
Tools and machines used include horizontal and vertical band saws, belt sanders, drill press, mill, lathe, and various wrenches and screw drivers.
Problems Encountered
During the building of this machine, the team ran into obstacles at every corner. As a team we were able to brain storm on possible solutions and quickly implement them so that we did not fall behind schedule.
A few of our most difficult problems included:
- Lid Removal
- We had trouble consistently lifting the lid of the Petri dishes. After almost every adjustment to any part of the machine, the lid removal components needed to be fine tuned. These components are now securely fastened to prevent readjustments in the future.
- Flask Installation
- Because the flask must be inverted to begin the filling process, we often had spills. This problem was resolved by choosing the correct length steel tube for achieving pressure equilibrium.
- Filling at the wrong time
- If a Petri dish failed to be brought down the conveyor belt, or the machine was done running, the fluid transfer process would still continue. We were left with a puddle of fluid not in any Petri dishes. This problem was fixed by adding a switch that only allows the fluid to be transferred if a dish is present.
Switch to activate the fluid transfer process only in the presence of a dish.