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Half a mendel with explicit over-reach?

Posted by jgilmore 
Half a mendel with explicit over-reach?
February 03, 2011 03:49PM
I don't have a mendel of my very own (yet) so the all of this post is gleaned from reading. Also it's possible that I'm solving problems which aren't problems because of my lack of direct experience in this area.

The bed hangs over it's frame on both sides in the Y direction when printing. Nophead's box had to be made bigger than the actual mendel because of this.

The Z axis can't go all the way to the top without banging the extruder gears into the top bars.

The extruder is harder to mount and unmount than it could be, and access to the extruder while it's printing could be better.

So I had a thought that went kind like this: If we mounted the X axis sideways and moved it to one extreme side of the mendel (such that the frame is now a right triangle instead of equilateral) it'd be really easy to get to in order to service, take pictures, etc.

OK, that's technically two fairly major structural changes: X axis being mounted vertically with the extruder mounted on the side, and changing to a right triangle. And then a third one in implied:

The bed would have to be much more cantilevered which would make it somewhat heavier or wobblier.

The bed would only stick out on ONE side instead of both. It'd functionally fit into a narrower space. Any desk you can set it on, it can print on. No worries about the bed hitting the wall behind the desk, because it'd stick out the front instead. You'd have to avoid walking into it (which could make getting up to use the restroom an adventure in timing in some places I've been in) but other than that it'd be fine.

The electronics could be mounted across the top right behind the extruder so they'd be easy to get to as well. Everything but the Y bearings would be right there. Even the Y bearings would be easier to access, because the bed wouldn't be mounted directly on top of them. You'd just have to turn it around.

It'd be kind of cool to have it print, and present the part so far out. You could access the whole bed, to remove it and replace it for the next part, or simply to service it.

You could also print two, one upside down, and make a box smiling smiley which would be kind of silly, but it does pack together better than the standard mendel if you want to do that kind of thing.

That space behind it could probably also be used for other things, like a spool of plastic?

I suppose that a really heavy print might tip it over. If you *did* use the back of it for your spool of plastic that wouldn't be a concern though. And with the Y bearings etc back there I don't think there would really be much danger of tipping.

Tipping the X axis sidways would lose some vertical travel as well. I think it'd be more than regained by having the extruder mounted on the side.

I'm building it with Baling Wire
Re: Half a mendel with explicit over-reach?
February 03, 2011 08:37PM
by turning it to the side you have reinvented the typical cnc.

I also had trouble getting enough z height for the repstrap I've been designing for the past year and 5 or 6 iterations.

Start making a mendel and end up with something else:
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Drop Box
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