Scaling Mendel to provide larger build envelope

What problems will I face scaling the mendel design to provide a larger Build Envelope.

My ideal envelope would be 400mm x 500mm x 1400

What are the implications for the electronic control system?

Thanks in advance

David

Electronics: Nothing that I can think of.
Firmware: May need some changes, but maybe not...
Mechanics: Here is the big problem. You will need a heated bed in this size and the frame must be stable. You will need M10 or more likely M12 threaded rod to provide the needed stability at this size (or a mechanic redesign). You do know that it will take forever to print out an object that fills this build envelope don't you?

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Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
BLOG - PHOTOS - Thingiverse

I'm thinking a 1400 mm tall print may fall over during Y axis moves, coming unstuck from the build platform. I'd suggest scaling a design more like the Ultimaker, in which the built platform only moves in the Z axis. Ultimaker's configuration has also run at speeds much faster than the Mendels, which you'll want for a build that large. Another benefit will be a smaller footprint, since you won't need room for the platform to move in the Y axis.

Another consideration is that heating a build platform that large will require a lot of power. It will need it's own power supply, switched from the control electronics by a relay. You may also need to consider a heated build chamber for prints that large.

Start here:
http://reprap.org/wiki/MegaMendel
http://reprap.org/wiki/1X2_Tallcat


I'd suggest scaling a design more like the Ultimaker, in which the built platform only moves in the Z axis.
I'd make the long axis horizontal. Forrest is doing up a double-wide Darwin-like machine which should be fun.

Edited 1 time(s). Last edit at 04/08/2011 06:01PM by SebastienBailard.

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-Sebastien, RepRap.org library gnome.

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Bearing in mind increased loads I have been looking at the specs for the STP-MTR-23079 using the AVR-Based stepper motor Driver.

Has anyone any experience of this combination?

Thanks in advance

david

You may want to follow Prusa's progress on the monster.

http://www.flickr.com/photos/prusajr/5607512102/in/photostream

Thanks will do.

I am also looking at using aluminium extrusions for a rigid frame rather than a triangulated structure.