As we noted in the last post, the whole wallace frame came out shaky for us (we printed it out on a Makerbot Cupcake basic).
Some problems, prima facie were –
- The Z rods were open-ended (and we have to live with inaccurate rods, being in India, and wanting to keep everything ‘reasonably’ priced :P). So it was all wobbling when we moved Z up and down.
- The base blocks didn’t come out as accurate as we’d have liked, so when we actually screwed on the LM6UU bearings on them, their centres were not aligned on the same axis, so the Y rods were jamming.
- The Y idlers’ mounting arrangement was not clear from the available information online. So we printed out printrbot’s arrangement. That worked, but the timing belt was on one side, and we felt it is going to give an eccentric “tug” to the table – if you feel what I mean – and not pull the table along its centre, as we’d like.
- Then, it looked somewhat like a criss-cross structure of screws and rods. Much less so than the original Mendel or the Orca, but still, the looks didn’t quite dig for us :P. (disclaimer – the definition of beauty is subjective :P).
So we went back to the drawing board (CAD software?) and redesigned an entire exoskeleton for it, and removed quite a few pain parts, as in this pic:
You can see the X and the Z axes of the Wallace/Printrbot frame inside. But the bases are gone.
The second step was to get them laser-cut in shiny black acrylic, and assemble them:
- Dinesh and Praveen assembling the first IndiaBot prototype 🙂
And the result (with its first sketch – when we tied a pencil in place of its hot-end):
(Of course, the right panel is yet to be attached on)
The next job was calibration, for which we had it draw a Yin-Yang. Here is a video for your viewing pleasure:
(the pen is not attached securely to the base, so the wobble in the sketch… but heck its just starting to print!)