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Issues

Issues will now be listed in an unordered manner.

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This pertains only to the insertion of the test tubes into the mechanism. These were a pain in the ass to put into the mechanism. And once inserted, the tubes were extremely loose, as seen in the video below. An alternative to as what is shown in the first view videos at the top was to wrap tape around the test tubes and press them flush with the rotating carriage. This was sufficient for testing purposes. In future designs it will be important to ensure the test tubes are easy to insert into the mechanism.

Top Bearings

Bearings at the top of the mechanism were all loose, did not seem to impact performance, something worth noting.

Dirt into Test Tubes

This is potentially the biggest issue for the entire mechanism. Even when pulverized dry dirt is attempted to be put into the test tube by a pouring action, no dirt will enter the tiny hole in the plastic cap. This issue will need to be corrected for in the next design.