I have built several 3D printers 2 prusas and 2 mendel90 I like the Mendel90 the best it was designed by a guy on the reprap forum under then name of nophead he also sells (and they are very good) all the plastic parts for both types.

Wify The M90 frame is mdf I have a spare one if you want it and can collect you can have it free... Clive

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