English
Forums
English forum
Original Prusa i3 MK2/S
General discussion, announcements and releases
MK2S after 9 months.
 
Notifications
Clear all

MK2S after 9 months.  

    Last Post
  RSS
spark
 spark
(@spark)
Reputable Member
MK2S after 9 months.

My MK2.5 upgrade kit arrived. Parts that were removed have some signs of wear. Most useful to MK2S community is wear on ABS parts.

Some findings from disassembly (ordered from critical to nuisance):

  • Heatbed thermistor wire damaged by spiral wrap and fatigue. Wire replaced with silicone high flex 24 awg. Spiral wrap replaced with mesh wrap as found on MK2.5 and MK3.

  • Noticeable melting on heatbed spiral wrap at mid-point.

  • ABS nozzle part warped so badly it snagged on prints. (sorry no photos, long since discarded)

  • Belt detached due to ABS warp and poor capture design. (note MK3 revised design)

  • High power cables for heaters show noticeable stiffening vs. new MK2.5.

  • ABS warps over time if continuous pressure is exerted.

  • ABS, though capable of resisting up to 90°C, shows degradation near hot-end.

  • ABS with low infill is very brittle against impact. Will shatter under load when hit.

  • ABS transfers vibration causing unwanted noise that gets worse as parts warp-loose over time.

  • My MK2S had stainless steel guide rods which scored noticeably.

  • PEI sheet was replaced 3 times due to rips from scraper accidents. Roughly a table spoon of blood was given to FDM/FFF gods.

    • Use and environment notes:
    My printer is working nearly 3 times a week printing prototype parts in ABS and PETG. No real success with PC.
    Printer is housed in a passive enclosure capable if 50°C.
    Paving stone base is used with custom TPU feed dampers.
    Belt has been replaced with genuine Gates GT2.
    X and Y guide rods and bearings replaced with Misumi.
    Idler pulley replaced with same as stock diameter toothed versions.
    Custom belt tensioners installed after belt detachment. (stock belt was fine)
    Astrosyn dampers installed on all travel motors.
    On my third E3D v6 sock. (heat wear degradation)


    MK2S kit owner since 8/15/2017

    Posted : 06/06/2018 3:56 am
    BillC
     BillC
    (@billc)
    Reputable Member
    Re: MK2S after 9 months.

    Heat wear degradation on a silicon sock??? 😮

    Bill
    Tagaytay City, Philippines
    Founder member of Philippines Prusa Printer Owners FB Group
    Sponsor Pillars of God Academy in Bacoor

    Posted : 06/06/2018 1:53 pm
    MrMik
     MrMik
    (@mrmik)
    Honorable Member
    Re: MK2S after 9 months.


    Heat wear degradation on a silicon sock??? 😮

    Certainly, if you try to push the limits by printing PC or other high temp filaments. They roast and get brittle.

    Posted : 06/06/2018 2:30 pm
    Joe Prints
     Joe Prints
    (@joe-prints)
    Estimable Member
    Re: MK2S after 9 months.

    E3D recommends not using a sock above 300 C, due to that reason.
    I changed to the copper heater block and achieved noticeably improved temperature stability even without the sock

    Anything can be made better
    https://www.myminifactory.com/users/Joe%20Prints

    Posted : 09/06/2018 2:45 pm
      All forum topics
      Previous Topic
    Next Topic  
    Share: