Monday, September 04, 2006
Quick Briar Patch design charrette...
I've made the working surface gear much larger than it would likely be in reality.
Adrian offers these two critiques of the concept...
You can't easily use it for outlining at the fast speed, as that ideally needs
to be continuous round the shape.
When you're infilling you don't just run back and forth. You have to plot quite a complicated joined-up zig-zag (see my blog of August 13) to avoid turning the extrude head on and off all the time.
For the first, I can't see how for outlining that it will be much slower than an ordinary cartesian machine.
The second, however, is much more serious in my mind. The meat of the critique is that you'd have to turn the extruder head on and off a lot. That's absolutely true. Also, given Vik's experience, the Mk II has a tendency to dribble which can make a bit of a mess of the end product.
Adrian has developed quite an efficient ploughshare method of doing infill. Taking this approach can't take advantage of it.
I had thought that it might be better to just do the infil for a layer first and then trace the outline afterwards.
I've been considering reversing the polymer pump just a touch as a way of turning the Mk II off in a way that doesn't dribble. You can't do that with the existing Mk II controller board. That's all untried at this point, though.
Anyhow, that's where I'm at with the idea at the moment.
Need some gears? bolt on the gear platform and make 'em.
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