Best print bed design for Prusa

Dear All,

I would really appreciate some input on print bed design:

I am currently building a Prusa for students to use and would like to improve the
mechanics of the bed

Currently the bed moves on draw sliders (see pic) which work really well,
but the part I'm not happy with is the plate and springs underneath.
The bed is difficult to level well



I had used a fixed bed previously but having broken several pieces of glass
due to Z plunge I would prefer to have some flexibility

The UP! plus and the MakerBot use three sprung hand screws for leveling
but the underside of the bed is more accessible than the Prusa
The mendel max I had used a central IGUS rail which would have easier
to access underneath

Currently the bed plate is a 2mm aluminium sheet with a MK2 heater but
I think using thicker aluminum would be better? or a different design of heater

I really would any input or ideas on this

Many Thanks
Simon

You may consider printing some thumbwheels to turn the nuts under your bed, like these: [www.thingiverse.com]. The best solution would be to eliminate the springs entirely, and find a way to implement automatic bed leveling. Not only has it made a huge improvement in my print quality, but the improvement in quality of life is well worth it. You can literally just push print and walk away. No more hovering over the printer to make sure that the first layer comes out right, and no more pause/scrape/restart/repeat when it doesn't. All you will need is one 9g R/C servo and the latest version of the Marlin firmware.

Three point support/leveling is good. If you like your screw mechanisms, I'd move one of the front ones towards the middle and then you could use it for back-front leveling, and do the side-to-side leveling by adjusting the ends of the x-axis.

What's the problem with the Al bead or heater? I'd add a bunch of cardboard filler as insulation.