Hello,
Can someone explain me how i can adjust the home position of the vertex?
That depend in what direction you want to adjust it. On the Z axis there is just a screw that you turn under the block. On the X and Y axis it is a little more tricky sins there is no real buildt in way for it. Unless you want to mod the printer with a solution or be brutal and violate the axis clamps but i wouldnt realy advice doing that one 
// Marlark
The x axis needs to be moved 20mm
ok moved where? the X axis doesnt have any room in term of it’s home position realy to go further right so to say.
Do you have a picture that you can show what you mean and what you are aiming for?
// Marlark
I ve placed the heated bed in the middle of the aluminium plate so now the extruder needs to start his print 20mm more to the left
Ahh your using a smaller heatbed then the glass plate well. Do you actualy need to move it considering when you place a object you place it based on center of the buildspace dont you wish should mean it end up in the middle of the heatbed regardless if the home position is original.
What you can however do is extend the plastic peg on the x axel that triggers the endstop. But that means you need to change the buildspace size in the firmware or else your gonna knock the crap out of the steppermotor when the printhead hits the left side of the printer when it hits that side.
A 3rd option is to get a larger heatbed so you can use the entire buildspace.
// Marlark
You could put the glass plate on the heat bed.
My thinking is it will warm all of the glass so you don’t loose any print space.
I could be wrong.
I have never done this.
Printer settings - park position
or
Pinter settings - Printer shape
To change the home position you would have to move the end stops.
I have a original MK3 heat bed, and I use the orinal glass from the printer.
The heat bed is 1cm short on each X dimension, but the glass plate is heated completely.
So I do not care about the little difference in size.
best
Frank
And how have you mounted the heatbed, because the bolts are in the way for the glass plate?
Hi All,
at the moment I prepare a kind of report, how I made the changes to the Printer, including, the electronical stuff.
This will take a few day, but in short.
I took the alu plate with the glass plate and use the clips from the printer as clips.
Meaning, I clip them over heat bed and glass plate. They are not fixed.
On the first try, I drill new threads in the alu plate of the heated bed, but that was not good.
The clips did not hold the stuff in place.
Meanwhile, while printing PLA, I use only the glass plate with the clips and no glueing stuff at all.
60C on a clean glass plate will stick like hell.
Greetz
Frank
When I mounted my Mk3 heatbed, I originally tried gluing screws to the underside, but the hole in one of my bed support pieces is not perfectly straight so the gradual pressure on the screw keeps shearing the screw off over time even with very strong epoxy.
So for my second attempt I reused the original aluminium plate and mounted the MK3 on top, centred on the alu plate with a thin silicone sheet between for insulation. I drilled and tapped some M3 holes in the alu plate to match the mounting holes on the MK3, and screwed in some 10mm M3 bolts, with a couple of washers on the alu plate side so the bolt just sticks up enough to hold the heatbed in position without actually screwing it down. The bolts stop the heatbed from moving from side to side, and once the glass is mounted on top it is perfectly secure, and the slightly floating way of mounting seems to help keep everything flat.
To secure the glass, I glued some small neodymium magnets (10 x 2.5mm) to the sides of the aluminium bed plate and the underside of the glass, positioned where the plate is wider than the heatbed. They aren’t completely necessary but I used some printed parts as spacers to get them all lined up perfectly. The heat bed is 3mm thick and my silicone sheet is 2mm, so 2x 2.5mm thick magnets matches the height of the bed + sheet perfectly. This actually works really well, the glass can be easily removed for cleaning, applying glue, removing prints etc. and it also seems to give a nice even height all around the bed, and the magnets are easily strong enough to hold the glass and heatbed in place.
I can take a pic of the setup if anyone is interested. I tried printing some replacement bed clips but despite trying various materials I never found anything that worked that well, and using binder clips was too much of a pain of accidentally smashing the print head into them.