Homebrew PCBs

>10 micron repeatability is pretty amazing. Just wondering out loud... >would it make sense to mount the printer head on the spindle of a CNC mill?
>Either way you do it, I don't see how you can do second and subsequent
>sides without multiple registration features for placement and >alignment. (It sure would be nice to just print out 11 layer boards >with micro-vias and plate-throughs. I'd settle for just 7 layers. :-)

I�m using X-axis of Epson printer, I changed DC servo by DC motor with gear reduction to 
have much uniform speed. I add some additional support to avoid shaking. I have also 
slotted opto-coupler for starting point detection. Linear operating range of opto-coupler is 
300 micron meters (0-3.3V = 0-300 micron meters). I�ve a calibration sw operating during start-up.
Assume that you have reference dowel pins on the bed of printer 1st pin is at position 
Y=0 X=Xmax/2 (center of X axis)and 2nd� pin is at Y=Ymax,X=Xmax/2.. 
Let�s draw a line passing through center of these pins a call it axis of rotation.
Let�s prepare our image centered on this axis of rotation. If you rotate image on 
this axis everything will be matched in theory. 
The method I explained is used by LPKF PCB milling machines. 

>Volkan, I missed the mechanical and control details if you posted >them. I'm curious about the Y-axis drive, and the print head control >signals and timing. Were you able to find those on the web?

There is no web at least I know which explains operation of Epson heads. 
I learned it by reading Epson patents and by measuring actual printer. 
If you really interested with that and want to design yourself I can help you, 
but implementation details are most probably off topic for this group and we need to contact offline.
Y-axis has very precise servo motor coupled with 10000 pulses (in quadrature decoding). 
I have also precision linear slides on Y-axis.

Cheers,
Volkan



      

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