Rostock Z Manual Control

rcvail

I am having difficulty with the z manual control.  When I press the Z up button for 1mm the printer moves up around 210mm instead.  The x and y move perfectly.  Would this be RH issue, pin issue under z stepper driver or Marlin issue?  I am running arduino 2560, ramps 1.4 and nema 17 stepper motors.  I do not currently have end stops installed which could throw off the z movement.

Repetier

Check in host set homin position. Should be set to your z max coordinate and i guess you have set it to 0.

rcvail

I don't see homin selection.  However, I have set Home Z to 100, Printable Height to 100mm, and Park Position to 100.  It just seems that when I manually move the X or Y axis it appears to move correctly.  When I move the Z axis it move over 100x more than it should.

rcvail

I think maybe adding 3 jumpers to the pins under the z stepper driver is causing the z axis to move too fast

Repetier

Ok, but for rostock you use all 3 motors for z moves so that would also affect x and y moves if microstepping is wrong.

What happens if you move
G1 Z100
and then
G1 Z99

goes the latte rmove only 1 mm from Z=100 then?

rcvail

I placed the extruder nozzle on the heated bed in the center at the bottom of the printer and tried these commands with the actual movement results:
G1 Z100 moves 31.5 cm
G1 Z99 moves 8 cm
G1 Z10 moves 22 cm
G1 Z5 moves 22.5 cm
The Z command for distance does not correlate to the actual movement of the printer in the z direction if I start at the heated bed.

However, if I try again from the center of the heated bed and run a G1 command.  Wherever it stops after that command, the printer will then work correctly if you type in a new G1 command.

It does behave strangely though, because if I ask it to move an identical distance, say 50mm twice in a row, it will only move the first time.  However, if I change the distance each time, it will move correctly each time.

Also, if I leave the extruder in the middle of the print volume and hit "Z" down it will not move at all.  If I hit "Z" up it will go up until it hits the top of the machine.  If I hit the "home" button it will FLY to the top and crash very badly.

Repetier

I'm not sure what is wrong here, but I would at first check the free ram. Should be at least 900 bytes or you get very starnge and wrong behaviour from memory overwrites. That might explain why nothing makes sense at the moment.

Reduce subsegments per line until you have enough free ram.

MartinH

 I do not currently have end stops installed which could throw off the z movement.

so how does the printer know where it is.

rcvail

Repetier said:

I'm not sure what is wrong here, but I would at first check the free ram. Should be at least 900 bytes or you get very starnge and wrong behaviour from memory overwrites. That might explain why nothing makes sense at the moment.

Reduce subsegments per line until you have enough free ram.

So, my computer has enough ram and this doesn't appear to the be the issue.  Like MartinH said above, there doesn't seem to be any way for the printer to know where the extruder is located.  I cannot set a "home" like I can with my other printer when I set x, y and z.

When I run the very first G1 command, the printer seems lost and just arbitrarily runs up vertically to some point.  If I run the G1 command again, the printer appears to have established a "base" point and then can act correctly with the G1 commands.  I did install sainsmart hall effect sensors last night, but the sensors did not come with magnets so the stops are working yet.

Repetier

Deltas need to be homed first before move commands can make sense due to nonlinear behaviour. Since you said homing is not working correctly I guess you did not home at the beginning.

You said your computer has enough ram - but the printer needs the 900 byte ram. How much free ram does firmware report on connection start in log?

rcvail

I discovered the Deltas will not work without endstops and it is pointless to try.  I did install the hall effect endstops and they pass the "open" and "triggered" test.  I made a bunch of changes and believe I am closer to having it work than before.  The problem I have now is with Marlin and uploading the reconfigured sketch.  I get this error:

Arduino: 1.0.6 (Windows 7), Board: "Arduino Mega 2560 or Mega ADK"
Marlin_main.cpp:233: error: expected primary-expression before '=' token
Marlin_main.cpp:233: error: expected `}' before numeric constant
Marlin_main.cpp:233: error: expected ',' or ';' before numeric constant
Marlin_main.cpp:233: error: expected declaration before '}' token

And this portion of the Marlin_Main.cpp tab has this highlighted.

float max_pos[3] = { X_MAX_POS, Y_MAX_POS, Z_MAX_POS };

It is probably something simple in the code, but I can't identify it!

rcvail

Ok, so I found several errors with Configuration.h.  I was able to fix them and now the printer functions properly on the x,y and z axis.  Everything seems to be working except for the printing.

When I load the print and run slic3r everything looks good.  However, when I hit print, the z-axis decides it needs to go to 1,000+ mm to start and thus crashes into the top.

This is a tall, custom delta and I have 1,000mm rods, but my z-axis is only 505mm.  It appears the printer is homed correctly with G28 and zeros correctly with G1 Z0.  What could I check that would force the z-axis to change to over 1,000mm when I hit the print button?

Repetier

Sorry, we are repetier forum and I have 0 experience with marlin delta. Here I would advice a marlin forum. Maybe some marlin user will show by, but marlin forum should give faster and better results.

rcvail

Actually, thanks for responding.  I had left over some startup G-Code in Slic3r which was messing up RH.  The g-code had been used for a cartesian printer and doesn't work with a delta.  Seems to be trucking now!