Home issues (for want of a better description

Hi all

Ormerod 2

Ok, after printing a perfect snowman, I couldnt get near the printer for a couple of weeks due to work.

Saturday I wanted to reprint the orthagonal compensation pieces with compensation included to see whether I got the axes right.

First the Z sensor is misbehaving (I am quite accustomed to this by now) - it reads 1015 to 1020 constantly, and this time nothing I do will fix it ( checked all the usual wiring suspects)

So I decide to manually home X and Z. (have done this with Z before)

So I get the nozzle down on a piece of paper until I can just move the paper, and Zero the Z there.

Then I shift X till the sensor is above the tag - and I set X to Zero.

Home Y normally

Send the orthagonal compensation command
Bed is manually as level as I can get it, and since the sensor is acting up I don't set automatic bed compensation.

Now when I start printing it appears the printer starts going through some type of homing sequence, and long story short, it starts printing with Z about 10mm off the bed.

I repeated the whole process several times, with and without orthagonal compensation command being sent, also tried sending the command before and after the homing procedure described above.

Also tried the snowman again, same result.

Am I missing something obvious?

Thanks

James

the homing is done in your g-code file. if you print the snowman right from your printr you might find a line that reads:

G28 ; Home all axes

delete this line from the file and it will start printing without homing of the axes.

If the sensor is reading that high constantly - something like "0 (1015)" - one possibility is that there is a bad crimp connection at one of the ends of the ground wire in the sensor loom. On the O2 this is the yellow wire.

Edited 1 time(s). Last edit at 12/15/2014 03:38AM by dc42.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

..or if you want to slice it yourself, attached Axis.stl

Erik

Thanks guys

Dave, I also suspect a bad crimp - in the past fiddling with the wires has got the sensor going long enough for homing and bed comp, but seems to need a little more effort this time. Probably just going to redo all the connections when I have time. I am sure your sensor board will solve this too :-) - sent you PM earlier regarding that.

DasBasti - I also thought was there must be homing in the file - wanted to check, was in a hurry and my finger slipped when pressing the sd-card to remove it - the card shot out of the slot and disappeared into the depths of my work-room/study. After 2 hours of searching I just gave up and decided the 3D-printing gods were not on my side! I should put the "shooting out sd-card problem" in a seperate post for everyones comic relief as I am sure I am the only one to have achieved this!

Eric - I have yet to attempt my first solo-slice. I have a few days off now so if my little daughter gives me a chance I will hopefully be able to spend some time with the printer!

Thanks again

James

Edited 1 time(s). Last edit at 12/15/2014 04:47AM by jamesf.

Quote
jamesf
I should put the "shooting out sd-card problem" in a seperate post for everyones comic relief as I am sure I am the only one to have achieved this!
James

No you aren't! I once spent nearly an hour searching after doing exactly the same thing as you describe, then decided that it would be quicker to go to Argos and buy another card. When I got back with the new card I immediately spotted the old one wedged near the Y motor - it must have hit something and bounced back to the printer!

That was before I changed to DC42's firmware and web interface - now I hardly ever need to remove the SD card.

Dave

Dave you made my day!

I was thinking the old age must really be catching up! Unfortunately my search was fruitless. I heard the damn thing hit the desk in front of the printer, but absolutely no idea where it went after that. Also suspect it may be jammed in printer somewhere, and I just know that five minutes after putting a new card in I will find it!

Have just downloaded DC42's firmware. Hopefully I will get that installed today or tomorrow.

Many major all-night supermarkets stock SD cards (usually near the phones), so unless you lose it on a Sunday evening you can get another one reasonably quickly ...

Dave

Quote
dmould
Many major all-night supermarkets stock SD cards (usually near the phones), so unless you lose it on a Sunday evening you can get another one reasonably quickly ...

Actually have a few spare - but one keeps on thinking "I'll find it now" - I mean - how hard could it be!