Print calibration..

ANy good guides on tuning in printing and thing like step per mm and so forth? Or is it more of just trial and error while twaeking slicer settings? Thanks everyone.

The best way to tune steps per mm is to use a pair of calibers and actually measure the displacement of the carraiges when you do a 125mm move

eg start at z=MAX and measure the idstance of each carraige from the top of the printer, now move move down 125mm and make a new measurement,

New SPMM=old SPMM *125/measured movement

Once you have the steps per mm correct the next thing to do is get the XY scale and orthographic calibration correct, and the best way Ive found to do this is to print an an octogon about 160mm AF 5mm high with a 5mm wall thickness, keep the part as large as your printer can ahndle but small enough so you can print it quickly.

Once its printed, measure the across flats measurements as accurately as possible without removing the part from the build plate

Before checking the across flats measurements check the wall thicknesses of the 8 walls these should be evenly about 5mm, if they differ then there is probably something loose in the build

There are four across flats measurements in total, the easiest to set first are the X and Y scale just measure the AF in the X and Y direction and correct the scale using M579, but it this is out significantly then its likely that there is an error in your steps per mm figure or the arm length

Now measure the diagonals, these should be the same as each other (and the same as the X and Y flats) if they differ then you need to correct this using M556, by setting the X parameter to equal the Difference between the two diagonals

The M556 has two more compensation parameters that can be set, these are for the XZ and YZ plance and you need to print an alternative shape to set this, but getting the XY plane set right before will make this a lot easier and save you printing time on a more time intensive part.

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RepRapPro Mendel 3 Tricolour
RepRapPro Fisher
-Carbon Arms
-Easy adjust Carriage+effector
-axis stiffness mods
HE3D -600 delta
-Duet 0.8.5
-PanelDue
-DC42 Height probe
-RobotDigg metal components
Simplyfy3D
RS Design Spark CAD

Are you tuning/calibrating the extruder or the effector?

I would start by reading [reprap.org], followed by [minow.blogspot.com], which is how I got started. Then you might try googling your printer for any related guides from other users.

Thanks Kurzaa!

For those following... Kurzaa's first link is for Cartesian rather than Delta printers, but the extruder calibration may be useful. I'll leave that for later. The second one is obviously for Delta, and it looks like the 30 May 2013 section relates to both Repetier (which is good for me) and Marlin. It appears to depend on end-stops at the bottom rather than the top. This calibration is done by modifying the firmware.

I also found [escher3d.com] which generates M665 and M666 G-code commands for Repetier (and several other firmwares). I'm going to try this approach first. Hopefully after I've done that, I'll understand a bit more and may then try cminow's firmware-modification approach since it seems to offer more parameters to fiddle with.

For people with Zonestar D810 printers, from the Repetier source code provided by the vendor,

• Steps/mm = 80
• Initial diagonal rod length = 230
• Initial delta radius = 100
• Initial homed height = 330?
• Printable bed radius = 90