[Closed] E3D Volcano Height Adjust  

Re: E3D Volcano Height Adjust

Hi Don,
I wish I had more info for you. I was under the impression this would be automatic. As my bed height is 3mm higher than stock, calibration automatically trimmed 3mm off of printable volume. 8.5mm more for Volcano should not be an issue for the firmware as is. Did you not find this to be the case when you re-positioned the PINDA downward? Sounds like the answer was no.

Re: E3D Volcano Height Adjust

The PINDA was fine, and I can even get a good "home" position, the issue is when I go to do a calibration for xyz the calibration routine (I assumed) has an arbitrary Z height to start from and since the Volcano is about 5mm longer than a standard nozzle, it crashes into the bed and then starts scraping across in search of the first calibration point.

Re: E3D Volcano Height Adjust

Yes, I see that. Z-cal and Home both use PINDA to set the height but seems XYZ cal completely relies on fixed firmware value as "safe" scan start distance. Disappointingly poor logic routine. I see then that I was just lucky with my 3mm being well within firmware "safe" margin. But, a further 8.5mm (nozzle Z difference from standard v Volcano) crashes my XYZ as well. Quick-draw trigger on reset button saved my PEI sheet, but this is quite short sighted logic design on Prusa Research's part. This is definitely worthy of a firmware revision, it would take no memory or coding to add PINDA homing routine prior to XYZ cal so no manual input is ever necessary. We should put in a request for this change, XYZ cal should never have been decoupled from PINDA home.

Re: E3D Volcano Height Adjust

That would solve it! Unfortunately I don't know how to put a request in like you mentioned :/ . Plus I would rather not wait for Prusa to release another firmware update to get these prints going!

I have been trying to use the firmware editor utility posted in the "One-click script to modify and compile Mk2 firmware on Windows" thread and it works great, I've even (with my limited coding skills) found the Zmin height to make the adjustment, unfortunately I can't get the program to compile even before I've modified anything so I can't reload the firmware to see if my changes have had the desired effect.

Re: E3D Volcano Height Adjust

You'll need to compile using arduino IDE, following the instructions on github. If you like, I can try compiling it for you, if you point me to the code that needs changing. I just glanced over the source, but couldnt find it yet.

I also added an issue on github regarding this:
https://github.com/prusa3d/Prusa-Firmware/issues/205

Re: E3D Volcano Height Adjust

Someone replied on github with a solution that works for him, and makes sense: reduce maximum Z.

I changed
#define Z_MAX_POS 210
into
#define Z_MAX_POS 202

in Configuration_prusa.h, which I based on 1_75mm_MK2-RAMBo13a-E3Dv6full.h
Which I think is correct for all MK2S's (source code also contains config files for RAMBo10a, which Im guessing is for MK2 or older?)

I compiled the sketch, but I have not tested this. Two hex files are generated by arduino, one with and without bootloader. I honestly dont know which one you need. So if you dont know either, wait for someone to enlighten us 🙂

If you do know, you can download the hexes here if you want to try:
https://drive.google.com/open?id=0B5bj91OWg5HvQkpnMmIzSU9UQnM

Re: E3D Volcano Height Adjust

Interesting, I figured it would be the minimum (Z_MIN_POS) figure. I was looking at these:

I'll have to test out the info you found tomorrow. Thanks for helping with this! I emailed Prusa tech support, hopefully they'll have a way to help. If they do I'll update this thread with their info.

Re: E3D Volcano Height Adjust

Im quite sure Z min is not the correct parameter. That just defines how low you can move the nozzle relative to Z home position, and with a properly positioned pinda probe relative to the nozzle, that value shouldnt ever change.

Changing Z max makes complete sense. It defines the distance between the bed and the top of the gantry and you actually do lose Z height when you install a taller hotend, there is no way around that. And someone else, a firmware contributor on prusa github, confirmed this is the way to do it.

Ive printed my modded extruder body, and I will pick up a volcano clone today or tomorrow (my brother has a spare). I'll assemble everything when my new bed arrives (I ruined my stock bed 🙁 ) and try it myself.

Re: E3D Volcano Height Adjust

What extruder body did you use? I'm still shopping for a good one. Right now I've got a temporary mount for my pinda and hopefully it'll be good enough to print out a nice one.

I'm pretty unfamiliar with github. where is the 3d printing software or forums or whatever on there?

Re: E3D Volcano Height Adjust

I tried both of those hex files and my printer didn't seem to like either. After uploading I got this:

Reinstalling Prusa firmware got me back to where it was and the new firware (released the other day) still crashes the nozzle during xyz cal.

Re: E3D Volcano Height Adjust

What extruder body did you use?

The one I linked earlier:
https://www.thingiverse.com/thing:2535500

I have not mounted it yet.

I'm pretty unfamiliar with github. where is the 3d printing software or forums or whatever on there?

Well, thats not what github is. Its a repository for opensource software, like the prusa firmware. It does have issue tracking and discussions. I opened the issue here:
https://github.com/prusa3d/Prusa-Firmware/issues/205

Re: E3D Volcano Height Adjust

I tried both of those hex files and my printer didn't seem to like either. After uploading I got this:

Eck. Thats not good. Do you have a MK2 or MK2S?

Re: E3D Volcano Height Adjust

MK2.

Well, I got a colleague to help get the firmware to compile, and I changed the Z_MAX_POS from 210 to 202 and worked like a charm. I'm back up and running with the volcano and everything seems to be working well!

Re: E3D Volcano Height Adjust

Don, great to hear! I've been following this thread to prep for install, but I'm curious, do you feel others would encounter your compile issues? If so, could you describe how your colleague was able to get a good compile for you to use?

Re: E3D Volcano Height Adjust

Ya, he said he had to use Arduino 1.6.8, and firmware, v3.0.12. I'm going to have him set me up so I can edit the firmware too, the next time we get together (this was all done over the computer), so I'll update this if necessary.

FYI, I measured the difference between the old and new heater block and it's about 4.5mm difference, so going a full 8mm is probably overkill but it worked. Just shaved a couple extra usable mm off the Z envelope and probably made calibration take a little longer.

I'm also printing out the extended PINDA holder extruder body from the " http://shop.prusa3d.com/forum/improvements-f14/mk2s-pinda-probe-version-2--t5807-s10.html " thread and it looks like its gonna work well, just have to get this new nozzle dialed in a little better. Oh, it does a much better job heating the material!

Re: E3D Volcano Height Adjust

Is it normal when uploading your own modified firmware to get "avrdude: verification error, first mismatch" errors? I don't get this when I flash the official precompiled firmware (I also got the crazy letters on the LCD when I tried the hexes that bob.b2 put on Google Drive. I am using Arduino 1.6.8 and followed installation steps for the library and hardware folders.

Despite the verification errors, the modified flash did program seemed to work fine, and I did a XYZ cal, but I think it didn't save it because when I go to print it just dives straight into the bed when I try to print. Admittedly, it it said the calibration was compromised because it couldn't reach the front right plate position, but then said I only had a slight skew, so I thought it had saved it anyway.

Anyway, I've straightened out my Y carriage, but a later firmware update bricked my board, so I'm waiting for a USBtinyISP to arrive in the mail so I can recover.

Re: E3D Volcano Height Adjust

Well, I debricked it (I still get the avrdude verification errors though). Now the XYZ cal with my Z_MAX_POS=202 modified firmware passes fine & reaches all 9 points (I used a Y frame assembly helper https://www.thingiverse.com/thing:1846654 )

However, it still promptly dives into the bed every time I try to print.

What do I do next?

Re: E3D Volcano Height Adjust

I'm finally got back in business. I was modifying the 3.1.0-RC2 source, not 3.0.12 like I should have been. The Z_MAX_POS is super sensitive - 205.5 worked for me. Neither 205.0 or 206.0 resulted in a successful XYZ calibration.

My verification errors stem from the fact that I'd been using a USBtinyISP / Pocket AVR Programmer (adafrtuit / sparkfun) and they can't do more than 64KB of program memory, and the ATMega2560 on the RAMBo 1.3 board has 256KB. I've since been using a sparkfun Bus Pirate with the alternative STK500 firmware (while the Arduino 1.6.8 IDE can program via a Bus Pirate directly, it is painfully slow - well over a half hour. With the STK500 firmware, it is just a couple minutes). I've tried a couple times to program over the USB bootloader but I got timeout messages, probably related to the "Bootloader file specified but missing: C:\Program Files (x86)\Arduino\hardware\marlin\avr\bootloaders\stk500boot_v2_mega2560.hex" messages I've been getting (and yes I copied the hardware/marlin folder over)

Re: E3D Volcano Height Adjust

I've been mulling mods to accept Volcano without firmware change. Was on hold for 2.5 but with it being pushed back another month, I think this project is back on the books.

Planned kit includes:

One of them is working great, I even have micron level mechanical PINDA adjustment.

Unfortunately, it was a very difficult print so I will not be posting it.