Auto bed probing and compensation with G29 Development

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mikronano
Posts: 63
Joined: Wed May 13, 2015 2:42 pm
Location: Chicago, IL

Re: Auto bed probing and compensation with G29 Development

Post by mikronano » Tue May 31, 2016 6:52 pm

Weekend_warrior1999 wrote:Define probe as z end stop
Remove x0 y0 reference in g28 command just use "g28"
Ensure eeprom settings and chitchat are enabled

This should activate probe during g28 command
G29 command activates probe for bed leveling

Eeprom settings and chitchat enable the printer to recall the probe measurements for tram correction.

Also how I setup the "z" offset is to temporarily disable min_software_endstop for z. Then set z extruder offset to "0". I then upload the firmware and run g28. I then manually (via the smart controller) lower the z till the nozzle is at the desired height. Then read the DRO for Z on the LCD, it should be a negative number, this will be your new "z" offset. Change it, re-upload, test. Once happy, re-enable min software endstops.
Thanks for the help :)
The thing is that I have already tried all these things.
I have tried all the possible combinations between G28 and G29 commands and all the axes.
I have set up the probe clearances exactly the same way you described.
I have set up the servo (motor and pins) just fine.

But, for the love of all gods and goddesses on earth, it simply doesn't want to work with me. If not for the process I described before, the board will completely ignore the probe results (which btw are there, I can see them on the LCD, on Pronterface, everywhere!!) and starts printing up in the air, as if the probe never happened....

So, I have to admit that I've been beat and lately I'm trying to develop a 0.1mm touch switch in conjunction with the servo, that will allow me to probe not just the four corners but other points as well.
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Weekend_warrior1999
Posts: 15
Joined: Fri May 27, 2016 12:52 am

Re: Auto bed probing and compensation with G29 Development

Post by Weekend_warrior1999 » Thu Jun 02, 2016 12:55 am

Sorry, your still having issues, but i think i figured it out... I just bought S3D today to use on my known working autobed leveling Taz 5 (Had been using cura). All of a sudden when using S3D it would attempt to start printing about 15mm above the build plate...

I couldnt get S3Ds autobed leveling wizard to work, it just ran a G28 command, but under process settings under the scripts tab, then starting scripts tab, I entered:

G29 ; autobed leveling
G1 Z0 ; Z goto 0

After the G28 command that was already there and updated the profile.

Bam! It ran homing of XYZ, bed leveling, then began printing in the correct place.
Last edited by Weekend_warrior1999 on Thu Jun 02, 2016 1:07 am, edited 3 times in total.

Weekend_warrior1999
Posts: 15
Joined: Fri May 27, 2016 12:52 am

Re: Auto bed probing and compensation with G29 Development

Post by Weekend_warrior1999 » Thu Jun 02, 2016 1:03 am

It seems that there may be a bug in marlin or S3D where after the G28 command the new updated Z offsets arent relayed back to S3D for some reason or arent updated, so it uses the last known position ("raise_z_after_homing" in marlin firmware) as "Z0" on the DRO within S3D. So a quick hack "LOOSELY" used, would be to tell the printer to move where S3D thinks its at, "0". Then when the gcode is ran it starts at 0, and the printer starts a 0. Or instead of putting the "G1 Z0" in the starting scripts tab, you may be able to get by with using the "Z_PROBE_END_SCRIPT" variable in Marlin and put the "G1 Z0" there.

Weekend_warrior1999
Posts: 15
Joined: Fri May 27, 2016 12:52 am

Re: Auto bed probing and compensation with G29 Development

Post by Weekend_warrior1999 » Thu Jun 02, 2016 2:09 am

Confirmed: if you dont put the "G1 Z0" in the start scripts of S3D, but place it within the Z_PROBE_END_SCRIPT variable within Marlin, it starts at the correct setting. Just be sure your z offset setting within marlin are correct so you dont have a crash.

mikronano
Posts: 63
Joined: Wed May 13, 2015 2:42 pm
Location: Chicago, IL

Re: Auto bed probing and compensation with G29 Development

Post by mikronano » Thu Jun 02, 2016 9:46 pm

Weekend_warrior1999 wrote:Confirmed: if you dont put the "G1 Z0" in the start scripts of S3D, but place it within the Z_PROBE_END_SCRIPT variable within Marlin, it starts at the correct setting. Just be sure your z offset setting within marlin are correct so you dont have a crash.
I have to admit that I haven't thought about that! I'm a bit swamped at work these days and I didn't have to put it to the test. But as soon as I'll try it, I'll let you know.
One thing only: I did try to find that variable in my Marlin (2015Q3) but I could find it anywhere. If it is something that I'm supposed to put it on, could you please tell me at which point it should go and the whole expression? :?

Thanks again for all the help so far!
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zanthor
Posts: 35
Joined: Tue Nov 10, 2015 1:15 pm

Re: Auto bed probing and compensation with G29 Development

Post by zanthor » Tue Jul 19, 2016 2:14 pm

So I've just ordered the BL Touch for my Taz5 and it looks like I'm going to need to delve into modifying my firmware...

Is the source currently running on my taz5 with flexystruder available somewhere to modify?

kcchen_00
Posts: 1717
Joined: Thu Feb 19, 2015 12:42 am

Re: Auto bed probing and compensation with G29 Development

Post by kcchen_00 » Tue Jul 19, 2016 9:36 pm

Check https://code.alephobjects.com/diffusion/MARLIN/ ... looks like there is a TAZ 5 Flexystruder V2.

Weekend_warrior1999
Posts: 15
Joined: Fri May 27, 2016 12:52 am

Re: Auto bed probing and compensation with G29 Development

Post by Weekend_warrior1999 » Wed Jul 20, 2016 7:35 am

mikronano wrote:
Weekend_warrior1999 wrote:Confirmed: if you dont put the "G1 Z0" in the start scripts of S3D, but place it within the Z_PROBE_END_SCRIPT variable within Marlin, it starts at the correct setting. Just be sure your z offset setting within marlin are correct so you dont have a crash.
I have to admit that I haven't thought about that! I'm a bit swamped at work these days and I didn't have to put it to the test. But as soon as I'll try it, I'll let you know.
One thing only: I did try to find that variable in my Marlin (2015Q3) but I could find it anywhere. If it is something that I'm supposed to put it on, could you please tell me at which point it should go and the whole expression? :?

Thanks again for all the help so far!
I have to admit, I'm not running a stock version of Lulzbot's marlin, But rather a vanilla copy that I've personally adapted to my machine. This is due to the fact that I buillt my machine from scratch using the source files lulzbot supplies, and instead of using a Rumba board I went with a Ramps 1.4 due to cost and the ability to change out stepper drivers. I have had to also design my own board enclosure that mimics the original to house the ramps, heated bed bed relay and needed step down converters (12v, 5v). I also modified my ramps 1.4 board to use 24v rather than the normal 12v. They essentially run the same code, the only thing in marlin that is really different is one variable in which you define the board your using.

Weekend_warrior1999
Posts: 15
Joined: Fri May 27, 2016 12:52 am

Re: Auto bed probing and compensation with G29 Development

Post by Weekend_warrior1999 » Wed Jul 20, 2016 7:44 am

Here is my implementation of auto bed leveling. I tried to use a capacitive sensor, but couldn't get consistant measurement readings. This has worked really well for me. And the enclosure I designed.
Attachments
taz_custom2.jpg
taz_custom.jpg

eussrh
Posts: 41
Joined: Fri Jul 31, 2015 5:35 am

Re: Auto bed probing and compensation with G29 Development

Post by eussrh » Mon Jul 25, 2016 7:50 pm

Can someone tell me where on the TAZ board (TAZ5), the servo pins are? I want to use one for an retractable z-probe. Thanks

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