dwblair
commented
12 years ago Used a "physics toy kit for ages 8+" (will post precise brand later) to construct the assembly shown in this video. The basic geometry seems okay. Issues:
- The elevator assembly is clearly very wobbly. Guides for the 4 supporting shafts, and a secure attachment of the shafts to the elevator platform, will help a lot -- but is there a better design? E.g. the MakerBot apparently uses a motor to turn four screws simultaneously, each of which contributes to raising / lowering the platform. Will see if I can find the design online.
- The current design involves placing the stepper motor on the bottom of the elevator platform itself, adding to the payload to be lifted. This isn't ideal, but placing it at the base of the assembly would involve having the screw come up through the platform in this geometry. Maybe this is another reason to move towards the MakerBot - like design -- or at least to have the stepper motor turn the screw via some gears, rather than having the stepper motor axis identical to that of the single lifting screw.
Background
The project here is intended to make an inexpensive, motorized lab jack for use in a laboratory setting. Initially the plan was to modify an existing lab jack by adding a motor; now we've moved on to trying to create our own, from scratch. A first attempt is shown here, but is clearly far from being practical as yet.
Software / Tutorials
Bildr tutorial (via Sparkfun)
Hardware
Dimensions / measurements
Coupler: Lab jack knob to motor shaft
Questions