Jump to content
Ultimaker Community of 3D Printing Experts
plamelter

Z travel is going wrong way.

Recommended Posts

Hi All,

I built my own printer a while ago, Cartesian with fixed bed. Have printed several items successfully. Used other 3d slicing programs that had cura engines included and they printed fine. So, I wanted to try Cura 3.6 software. Have custom printer profile setup. It homes correctly, but second line of code that says Z15 lower build plate, well that tries to send my hot end through my fixed plate. Not Good.

When using Pronterface, Repeiter, or Craftware they know Z needs to go up , not down. I sure its simple, But so am I  Want something non fiddley Don't want to correct G-code Pre run every time I print..

Share this post


Link to post
Share on other sites

So.... The hardware is Ramps 1.4,

0.9 stepper motors

DRV8825 drivers

1.75 E3D Clone

Bowden tube

300x300 heated bed

 Marlin 1.3.6

Linear rails for X and Y

Z is trapezoid screw x 4

Looks like a Core XY machine, but X and Y gantry move up from bed.

Would like to know how to get Cura traveling in right direction,

As in Z15 should be 15mm above my fixed bed

Share this post


Link to post
Share on other sites
On 1/9/2019 at 10:55 PM, plamelter said:

It homes correctly, but second line of code that says Z15 lower build plate, well that tries to send my hot end through my fixed plate.

 

Well... the gcode that is generated by the slicer only contains the target coordinates, no moving directions. The comment ("lower build plate") is only valid for printers where the buildplate moves down though... but comments don't matter.

 

Printers usually don't support negative coordinates, so there is no way to move the z axis "through the buildplate" to a negative coordinate - but your device may be different?

How does the homing sequence and the calibration of the z-position work e.g.?

 

If your custom printer needs a different start script: you can modify it in the machine settings (in Cura).

 

Everything else is a task of the firmware / hardware of your printer.

If your issue is different - you have to explain a bit more - i guess...?

 

Share this post


Link to post
Share on other sites

You need to set up the printer such that Z=0 means the nozzle touches the build plate and Z=10 means the nozzle is 10mm away from the build plate.  Period.  It's okay for the homing position to be at Z=200 if that's what you need to do but it's NOT okay for Z to ever go negative.

 

Z=10 does NOT specify if something is moving up or down.  It specifies the distance between nozzle and bed.

 

So Z=20 may be "higher" or "lower" than Z=10.  But Z=20 is definitely "nozzle farther from bed".

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Our picks

    • Ultimaker Cura | a new interface
      We're not only trying to always make Ultimaker Cura better with the usual new features and improvements we build, but we're also trying to make it more pleasant to operate. The interface was the focus for the upcoming release, from which we would already like to present you the first glance. 
        • Like
      • 95 replies
    • "Back To The Future" using Generative Design & Investment Casting
      Designing for light-weight parts is becoming more important, and I’m a firm believer in the need to produce lighter weight, less over-engineered parts for the future. This is for sustainability reasons because we need to be using less raw materials and, in things like transportation, it impacts the energy usage of the product during it’s service life.
        • Like
      • 12 replies
×

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!