Bed Auto Leveling

I've attempted to follow all tutorials I can find about the new auto bed leveling, but I can't seem to get it working. When I issue G29 or G30 the servo flips my probe down and right back up. It never attempts to move the print head around.

I get things similar to this in my log

SENDING:G29
Bed x: 50 y: 90 z: 5.70
Bed x: 50 y: 50 z: 5.70
Bed x: 90 y: 50 z: 5.70
echo:endstops hit: X:90.00 Y:26.00 Z:5.70
>>>g30
SENDING:G30
Bed Position X: 130.00 Y: -14.00 Z: 5.70
echo:endstops hit: Z:5.70

I'm sure it's a setting somewhere but I have no idea where to begin.

I did attempt to un-comment - //#define DISABLE_MAX_ENDSTOPS

It made my printer act odd when I told it to home. Seemed like the Z axis would try to raise really fast then continue the home process as usual.

Hello

Let me comfort you that you are not the only one. Where it's not working. Whole weekend spended on get it working. Without results.

Mine probes. On g28 home. And g29 It probes home and two different places.

I guess it has something to do with the probe sequence, which its not changeable (without code skills)
And the position of the home switches.

As for now I am done with it. Just level the bed by hand until more people comes with a possible solution.

gibleteousjack, Try lowering your Z #define DEFAULT_MAX_FEEDRATE {150, 150, 10, 20} from 10 to something like 2-3 and see if it will home without jamming your Z steppers on home. My i3 will only handle 3 on the z feed any faster it will stall the Z steppers. Your autohome must work correctly before you the bed level. Then you have to play with the probe offsets. My X endstop is on the left and Y in the back and my probe is on the right side here is what my config looks like. depends on where you have your probe you may or may not need to change the offset to - (negative) like the readme states.The main thing is make sure your LEFT_PROBE is the same or more then X_PROBE.


// these are the positions on the bed to do the probing
#define LEFT_PROBE_BED_POSITION 53
#define RIGHT_PROBE_BED_POSITION 190
#define BACK_PROBE_BED_POSITION 190
#define FRONT_PROBE_BED_POSITION 95

// these are the offsets to the prob relative to the extruder tip (Hotend - Probe)
#define X_PROBE_OFFSET_FROM_EXTRUDER 53
#define Y_PROBE_OFFSET_FROM_EXTRUDER 14
#define Z_PROBE_OFFSET_FROM_EXTRUDER -2.8

@skew.

I have the exact same setup for my I3

The endstop for Y, is it set as end stop max or min in Marlin?

And what is your probing sequence?

Maybe you can post your whole config.h? It's driving me insane....

Edited 1 time(s). Last edit at 10/29/2013 08:09AM by Justintime.

I attached my Config.h And I also made a video showing the sequence of operation.
When I get home I will post my starting Gcode

Basically is like this
set hot end to 160c (keep it low so it doesnt ooze abs out while waiting for bed heat up)
bed set to 110c wait till bed gets to temp
set hot end to 230c (hot end will start heating up to operating temp while autolevel is working)
Auto home
Auto bed level
set hot end to 230c wait till gets to temp



Auto Bed Level Demo

Thanks Skew for the info and YT demo.


But you have similar behavior as I did. It probes three times (incl home) on the left and only one on the right.

When you watch the video of Alex it probes on all four corners. So you hav. All the level differences.

The second probe after the home probe is unnecessary.(I think) Thats what bothers me. Wish you could adjust the probe sequence. As
Did you measure after G29?. Is it really on level?

But again thanks I will try this evening

Edited 1 time(s). Last edit at 10/29/2013 11:10AM by Justintime.

Here is my starting gcode
M106 S110
M104 S160
M190 S110
M104 S230
G28
G29
M109 S230
G92 E0


My Z levels fine after autolevel. I can lower the Z to 0.00 and move X from left to right and my hotend drags the same on a piece of paper the same on both sides and the Z changes as the X moves. If you watch Alex's video his home is on the Max X&Y and ours is on the Min X&Y I don't know if the autolevel uses the home Z as a calibration point or is just to reference X and Y

Edited 1 time(s). Last edit at 10/29/2013 12:45PM by skew.

Turns out that my microswitch is broken.
It opens... But not when you hear the click.

So... First I will get a new one.

While you are ordering them, get *several* microswitches. They are dirt cheap, they break, and minimum shipping charges eat up money that could be better spent on other things.

Thanks uncle Bob,

But i bought the switches "old fashioned" in a store.... Yesss they still exists
So no shipping fees and yes I have bought two types. And when they break again.
I'll get new ones...

EDIT:
Mine is finally working right.... the problem ws the microswitch which was broken. Now you hear a second click after probing. And the levels are fine now....

I can finally sleep with rest...Thanks all

Edited 1 time(s). Last edit at 10/30/2013 03:46PM by Justintime.

I can get them at the store as well. The price is generally *way* cheaper online. I tend to bulk up on orders for small stuff like that.

Sorry for newbie questions, but what are the advantages of using auto bed levelling with Prusa?

Edited 1 time(s). Last edit at 11/01/2013 04:09PM by iCat.

If you move your printer around a lot, the bed goes out of level. If you have it bolted to a rigid surface it stays pretty level for a long time. Manual leveling takes a bit of time. If you need to do it often, the auto approach is the way to go.

Without trying to hijacke the topic, but i was locking for systems of auto leveling beds and until now i've only saw with servos and switchs, but had the idea, would it be possible to use a laser distance measurer? To much crazy?

I saw in the another topic. Thats still a wish. But more complicated.

A laser distance setup is much more expensive than a microswitch and it's going to have some interesting issues with a clear piece of glass. You can get some that are semi-reasonably for this application (they cost less than the price of the printer). At least the ones I have seen are no where near as accurate as the microswitch setup is (say 100 to 1000X less accurate). You can also spend a few thousand dollars on one that does a better job, but still not as good a job as the microswitch.

Hmm strange thing going on with my servo.

When I plug in the power. And not usb in computer.
The servo is going mad. It wants to go further than possible. And you see current drain on the lcd display.

When I first plug in usb and then the power it's test probing normal. But when Iam going to print the servo is going mad again.

The servo is broken? Or do iI have to search it in Ramps.

If the servo does what it's supposed to when you do the bed leveling, it's likely not broken. What you *may* have is a pin multiply defined in your firmware (pins.h or where ever). When the firmware is in bed leveling mode, the leveling code is what runs the pin. The rest of the time the firmware thinks there's a fan (or who knows what) on that pin and acts accordingly. As far as I can see from going through the firmware, there's not a lot of error checking / cross checking for multiple def's on the same pin...

Of course, I've missed things before.... I have not deliberately miss defined a bunch of things to see if it tosses errors or not.

This might help, [forums.reprap.org] you may need a voltage regulator. Or try setting the servo disable time in marlin