Re: Offsets in configuration (again) 8-)

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wretan
haha, sorry for my bad question about the SIN60 :D of course I know what value that corresponds to but I was curious about if the values should be changed if I made any other designs but I suppose that normal 120deg between towers.

You can use different angles between towers than 120°. I do not think it is a good idea. Forces are better distributed when the angles are 120°. With different angles, the part dimension errors and slack will have bigger impact too.

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wretan
I hope that my cad model can give the right measurements for the configuration in marlin firmware. I really hope that the actual geometry follows the theoretical model.

The model is simplified version of reality. Some real world dimensions do not matter for cartesian -> delta coordinate coversion (which is the only thing firmware is doing differently for delta bots). If your printer will have some dimensions slightly wrong it can be fixed during calibration. Things which will not be easy to fix (current calibration does not support these):
* towers not parallel with each other,
* all diagonal rods do not have the same length,
* bed not perpendicular to towers (but you can easily fix this by padding bed).

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wretan
One last question, have anyone tested using a photoelectric proximity sensor as Z-probe? I have tested a couple of sensors at my work and they work pretty good even on transparent glass. How does the software do the reading, only at "calibration-state" or would the input from a photoelectric proximity sensor mess anything up? It will probably keep detecting distance even when printing but maybe the software doesn´t care?

There was a discussion on google groups [groups.google.com] about optical z-probe sensor. As far as I remember they did not achive good precision and repeatability. I think the z-probe sensor is taken into account only during G29 command (the autolevel command) if you have ENDSTOPS_ONLY_FOR_HOMING defined. But I'm not realy sure. In my opinion, matrix based autolevel is useless if you require precision of the printed parts. I do not use it. I used z-probe only for initial calibration and then I removed it from the printer.