tgit-tech / rpieces-tabletopxyz Goto Github PK

The grbl firmware for this project needs to be modified so that the motors will released after a certain amount of time

See issue details at
TGit-Tech/GRBL-28byj-48#1

Ideally, Support for the Marlin firmware and Arduino Mega will need to be implemented.

Perhaps, the easiest and best way to produce limit switches is within the plastic racks themselves. Leaving a bendable sliver of plastic where two wires can be inserted. When the gantry presses the bendable plastic sleeve the wires touch. Below is a quick sketch of this idea.

I've added base-left, base-right, base-front members to solidify the frame after witnessing the Y-Axis movement twisting on an un-braced frame. When one Y-Axis motor gets stuck the moving side will actually twist the entire frame causing the front legs to move on the table and pinch the X-rack even further.

It was easy enough to add a few parts to stabilize the base of the frame; so they've been added but have yet to be tested.

Ran into a problem with the motors not being able to overcome the spike lift when the motor gear turns. Not to mention the jitter gotten from it which makes precision obsolete. As shown in the picture; when the gear turns each "point" of each gear will offset its standard position during rotation. When enough pressure is put on the gear it locks the rotation since it cannot over come the "lift".

I've also tried to print a herringbone gear as shown below; but this did not resolve the "lift" issue and also didn't print well. Tried to use sketch-up to round the herringbone gears more in a circle but it made quite a mess of the model. So the next approach will be to just add a circular ring on the outer edge to create a "bushing" type effect mesh between the rack and pinion.