Jump to content

Head expanding?


fuchs

Recommended Posts

Posted · Head expanding?

I recently levelled my printing bed with a dial gauge and got it around 0.1mm even.

As the Z-Axis endstop is a little bit pesky, i set it so that i had to turn the Z-Axis by hand some clicks when the print starts.

For the first prints, i had so turn the Z-Axis around 6-8 "clicks" (to raise it) and all went fine. After a few hours (3-4), i noticed that i didn't need to turn (adjust) the Z-Axis that much, only about 2-3 "clicks". 3 hours later the machine printed without any change in Z-height and i was very happy (altough a bit suspicious).

After 3 more hours (cumulated running time around 10-12 hours) i noticed, that the start of printing did dig into the tape on the printbed and i had to _lower_ the Z-Axis :shock:

So it seems that the printing head did maybe extend, eating away the clearance between the gantry/head and the printing bed.

I checked the screws on the head - they are still as tight as usual, also the clearing at the head mechanism are all the same.

Printing works now (in the evening) when i lower the Z-Axis. Will check what happens tomorrow morning, when the machine is cooled down.

Is it possible that the whole head (heater and nozzle?) expand after long prints?

I am yet running with the v1 hotend (v2 was delivered yesterday, but i didn't install it yet, as my v1 doesn't leak atm and i currently prefer printing and experimenting to maintenance :-P )

ADD: Or is this a case of the nozzle getting looes and unscrewing itself? I am starting to find very tiny traces of burned PTFE leaking between the aluminium heater block and the nozzle...

ADD2: Ok, in the morning the clearance between head/nozzle and printing bed is as small as in the evening, meaning that either in the course of yesterday the Z-Axis has moved/the printing bed did raise ("Ascension") - which is kinda unlikely - or the head has sagged / nozzle is coming loose.

  • Link to post
    Share on other sites

    Posted · Head expanding?

    Or maybe your z-endstop is pushed up a little bit when homing your z-axis.

    Thus after each homing, the endstop triggers a little bit later (i.e. z-platform higher).

    if you use the stock z-endstop and not a non mechanic one (like an optosensor or a hall effect sensor) and if the screws holding the endstop are not tight enough, i guess this can happen.

    Another possibility is that you z-platform itself went higher, because the screws holding it got unscrewed with the machine vibrations?

  • Link to post
    Share on other sites

    Posted · Head expanding?
    ADD: Or is this a case of the nozzle getting looes and unscrewing itself? I am starting to find very tiny traces of burned PTFE leaking between the aluminium heater block and the nozzle...

    Are you sure this is not leaking? My leaks were usually dark brown/black, I think PLA once it sits around a bit, as in a leak, burns a little.

  • Link to post
    Share on other sites

    • 4 weeks later...
    Posted · Head expanding?

    You know if you're going to use a dial gauge to level your bed to only 0.1mm even then you may as well adjust till you just touch the head and turn the M3 screws in by 1/5th of a turn (or whatever your need your 'lift' to be) instead.

  • 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 5.7 stable released
        Cura 5.7 is here and it brings a handy new workflow improvement when using Thingiverse and Cura together, as well as additional capabilities for Method series printers, and a powerful way of sharing print settings using new printer-agnostic project files! Read on to find out about all of these improvements and more. 
         
          • Like
        • 7 replies
      • S-Line Firmware 8.3.0 was released Nov. 20th on the "Latest" firmware branch.
        (Sorry, was out of office when this released)

        This update is for...
        All UltiMaker S series  
        New features
         
        Temperature status. During print preparation, the temperatures of the print cores and build plate will be shown on the display. This gives a better indication of the progress and remaining wait time. Save log files in paused state. It is now possible to save the printer's log files to USB if the currently active print job is paused. Previously, the Dump logs to USB option was only enabled if the printer was in idle state. Confirm print removal via Digital Factory. If the printer is connected to the Digital Factory, it is now possible to confirm the removal of a previous print job via the Digital Factory interface. This is useful in situations where the build plate is clear, but the operator forgot to select Confirm removal on the printer’s display. Visit this page for more information about this feature.
          • Like
        • 0 replies
    ×
    ×
    • Create New...