So i have over sized my copy of mendel http://reprap.org
At the time i started to build my repstrap i thought i may want to print something a bit large, so i decided to extend the print area, after looking at the design of mendel i decided to extend the bed as this would require the least amount of change, extend the drive and rails and bed to suit..
TIP: This worked out ok for me but for a repstrap, Start Small, something that prints smaller things but faster is better than something that is going to print slow but can go big.. testing becomes tedious... very tedious..
As i was saying i over sized my mendel and i figured it needs big motors the motors i ended up selecting the KL23-251-24-B by keiling inc. KL23-251-24-B PDF
this beast of a stepper has a full Nm of torque to drive my heavy axis
this stepper is being driven by the Gen3 MB2.3 stepper driver. nice stepper controller does the job..
i have used 4 of these steppers one for the Y Axis (bed) one for the X Axis (carriage) Z Axis (rails and carriage).. UPDATE: looking at changing the Z stepper for a bigger one or adding a gearbox to increase the speed of the axis. too fast and i miss steps.
these are all being driven by their own stepper driver, yes its over kill but MeH thats what this,blog is about Overkill Engineering a solution because my mega bodge solution failed.. one extreme to the next.
the MDF bed that i attempted to use for testing was about 250mm x 250mm it was held onto nylon bushes with cable ties ( lets just say it didnt sit flat), it was promptly replaced by a piece of glass that came from my work (it was excess.... i didn't steal it.... i swear...) it was nice and flat.. so i mounted that to perspex frame with springs in the corners and M4 screws to make adjusters this worked well, then came time to heat it.. i will leave that saga for another post all of its own..
so i found that you can use masking tape instead of heating your bed so testing of the rig progressed..