Help Request - AutoBed leveling

mpires

Hi,

A fast idea of what i'm trying to do and where i need some help.

I'm making a Delta Printer, and for the last 4 years i have been using marlin with Cartesians, but for what i read Repetier firmware is the firmware to go with a Delta printer, and for what i have see and configure is a very nice firmware.

After 1 week working with Repetier firmware, i was able to set few parameters and things are going, ofc that i'm making a lot of mistakes for sure, we just learn with mistakes .

So what i have is a Deta printer setup that i'm building my self, with Ramps 1.4 and arduino ( what money can buy for now ).

I think i did have success on set the basic settings, i can home and move axis without any issue the problem i'm having and probably is something i did wrong on the basic configuration, is that i can't set the AutoBed Leveling.

Once i do "G30" the printer test 3 point's near XYZ towers correctly without any problem, the problem comes after AutoBed Leveling and i send a test print file, the nozzle never have an offset from bed, i always get a crash.

I must refer that my Z-Prob is made with Hotend nozzle, i have a micro switch that is always close and open once the nozze touch the bed this is working.

After 3 days reading and testing some suggestion about this subject that i did found on the form, i'm stuck.

I appreciate any advise, suggestion... any thing that take me on the correct way to understand on how to configure correctly the auto bed leveling.  

Thanks, 

mpires

Ups... the commend that i did use was not G30 -- is G32.

Don't know why but i can't edit my question.

Repetier

Check eeprom that bed coating is 0 and z probe height is set correctly. Should be a small negative value in your case.

Also check you have

#define ENDSTOP_Z_BACK_ON_HOME 10

or greater or you might hit endstop at top causing missalignment. B eaware to reduce z length by the distance you add to it!

At least on first tests go down manually to see if z is now correct.

mpires

Ty i will check, but last night i did try remove autobed leveling to confirm my geometry was correct and i don't know why i have part of the bed where my nozzle go up.... i must try solve this problem first if not autobed leveling will never work as expect.

Correct me if i'm wrong,

First we must set the printer without auto bed leveling, align everything and make sure the nozzle can go every where with same offset from the table only then we should start the autobed leveling configuration.

Sry, im very new to Repetier, but i like what i did see until now, i'm just a bit lost at the moment.

I'm reading a lot of documentations about set Delta priters with Repetier but all them are different so i get confused.

If you can point me a nice documentation on how to set Repetier firmware that will save a lot of question that will appear.

Appreciate all your help you grant to this community. 

Repetier

The very special problem of delta printers is in deed that wrong parameters or imperfect construction (0.1° error is imperfect which makes it so hard) cause extruder go up/down depending on position. There are numerous ways to fix that if you google it. Even some tools that suggest correction based on error reduction

http://escher3d.com/pages/wizards/wizarddelta.php

which might help or not. Sometimes these tend to correct into a local minimum solution which is wrong, so keep your brain on when using it. Once you can not improve any further move to next step autoleveling. Use repetier-host bed height map feature to see how good your settings are.

Autoleveling assumes that xy moves do not change z and just compute some bed rotation to fix an error there. If you use a grid here knowing that even after you have calibrated printer as good as you can, you get a average plane that has best cross over fit, but may have bigger errors in some region (often at outside).

As a last resort we have a distortion correction and that makes the extruder follow the waves measured until a given height so your filament sticks good to bed.