Corexy (or similar) with extened x-axis

Hi,
Would it be possible to create a belt driven xy system with base mounted (stationary) motors, and have a "long reach" x-axis.
The problem is that the x mechanics will have to extend beyond the traditional corexy frame.

Here is an example of what I mean, though this machine have its x-motor mounted on the gantry.

ppmachine

You could always make a bigger gantry to reach over the edges of your bed on any motion system. There is nothing out of the ordinary in that machine if you ask me.

If you're asking can the X axis extend past the Y axis rails, then yes, just add a few idlers to make the belt turn at the XY junction and make it track parallel to the X rails as it heads to the end of the X rail, where it resumes the standard coreXY belt path. Alternatively shift the whole belt path out so it lines up with the ends of the X axis and just have a long tab coming off the Y bearing blocks to reach out to the belt. The question is why? Why not just move the Y rails out to the ends of your "extended" X rail and you have the same work envelope with fewer idlers or cantilevered belt clamps involved.

If the machine needs one axis to be much longer than the other, make the Y axis the long axis. The way corexy machines are usually built, the Y axis rails are supported by the machine's frame and the X axis is supported by the Y axis at both ends. The moving mass will be smaller if the X axis is the shorter one.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Look at CoreXY Drawbot. Crazy Engineer's Drawing Robot
Main problem is the cantilevered load, and asymmetrical forces.


Edited 1 time(s). Last edit at 09/29/2018 07:19PM by prot0typ1cal.

Interesting mechanism, but not corexy.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

How about RamXY?

Actually I've decided to try this one. Not core anything, one motor for each axis. Two very long belts for X and a plethora of idlers. But it may still work.

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Pilot65
Actually I've decided to try this one. Not core anything, one motor for each axis. Two very long belts for X and a plethora of idlers. But it may still work.

Do you move the whole tall gantry ? If yes, even worse than moving the bed. Not to mention long belt stretching, vibration.

Edited 2 time(s). Last edit at 10/01/2018 03:40AM by MKSA.

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"A comical prototype doesn't mean a dumb idea is possible" (Thunderf00t)

I wouldn't say it's worse than moving the bed. That's a moving portal style CNC machine, nothing out of the ordinary and fairly common. I'm not too sure how the kinematics work though.

For the record, that ramXY is basically the same things as the drawbot but with extra frame pieces. And iirc the kinematics are the same as coreXY/hbot despite TDD's assertions otherwise, it's a stripped down version of a coreXY frame.

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Trakyan
I wouldn't say it's worse than moving the bed. That's a moving portal style CNC machine, nothing out of the ordinary and fairly common. I'm not too sure how the kinematics work though.

For the record, that ramXY is basically the same things as the drawbot but with extra frame pieces. And iirc the kinematics are the same as coreXY/hbot despite TDD's assertions otherwise, it's a stripped down version of a coreXY frame.

I am not speaking about a CNC, but a 3D printer. Anyway, let see how it comes out.

Edited 1 time(s). Last edit at 10/02/2018 03:53AM by MKSA.

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"A comical prototype doesn't mean a dumb idea is possible" (Thunderf00t)

This is what your description brings me to mind

[www.youtube.com]