1. Got a question or need help troubleshooting? Post to the troubleshooting forum or Search the forums!

PEI Print Bed

Discussion in 'Mods and Upgrades' started by MeMine, Jan 24, 2016.

  1. jediknight0

    jediknight0 Active Member

    Joined:
    May 22, 2015
    Messages:
    110
    Likes Received:
    25
    OK, ordered.
     
  2. Schlomo

    Schlomo Member

    Joined:
    Dec 14, 2015
    Messages:
    36
    Likes Received:
    12
    Yeah, you basically hit the nail on the head with the problems I was having. I was able to solve most of them and am getting good larger prints now. There is another thread I had open about my bed leveling issues. Turns out the 2 front magnets were not touching at the same time. One was placed too far out from the factory. Got that sorted, and manually leveled my bed, prints great now.

    I also am having an issue with my print head flexing due to my carriage. I have an actively heated build chamber at 60c, and i think at spots its hitting closer to 70c and my printed carriage (PETG) will flex a bit. Im printing a new one out of eSuns ePC to help mitigate my issues.

    I haven't tried reducing the autolevel area, but may need to give that a try.
     
  3. MeMine

    MeMine New Member

    Joined:
    Dec 3, 2015
    Messages:
    4
    Likes Received:
    1
    I've redone mine once. It came off easy with a razor blade scraper and then I just used a razor blade to scrape the 3M off the glass. Took less than 30 minutes.
     
  4. Terry Reilley

    Terry Reilley Member

    Joined:
    Dec 21, 2015
    Messages:
    104
    Likes Received:
    20
    Can you use some sort of clips to secure the PEI rather than using the adhesive tape? I might have missed that in this discussion, so I apologize in advance if I did.

    This seems like a good idea for those of us (me) who chipped a print bed. I've ordered another, but have a feeling I will chip it again.
     
    #24 Terry Reilley, Feb 25, 2016
    Last edited: Feb 25, 2016
  5. anklagon

    anklagon New Member

    Joined:
    Jan 22, 2016
    Messages:
    10
    Likes Received:
    0
    Same here, i chipped the bed months ago, and thats when i installed the PEI.
    I didn't try to clip it, but i dont think it would give you reliable results..the PEI sheet that i bought is pretty flexible and i feel that the middle would lift quite a bit if not stuck with adhesive
     
  6. jediknight0

    jediknight0 Active Member

    Joined:
    May 22, 2015
    Messages:
    110
    Likes Received:
    25
    I tried using clips... it didn't work. Even though my piece of PEI was relatively flat against the bed, when I heated the bed the center of the plastic inflated like a pillow.

    I went to using adhesive and it works. First time I applied the adhesive to the bed then added the PEI... that didn't work so well. Next I added the adhesive to the PEI then added it to the glass bed... that worked better.

    All said and done the PEI works pretty well... but not perfect. I still have ABS parts that lift off the bed sometimes. It seems like the smaller the first layer, the more likely it is to lift at the edges. If I printed a 2cm square it's more likely to have edge lift than a 4cm square. Changing the z-offset to squish the first layer more helps, increasing the bed temperature helps, enclosing the printer helps, but there's no magic bullet in my environment.
     
  7. Multitech

    Multitech New Member

    Joined:
    Sep 12, 2014
    Messages:
    17
    Likes Received:
    0
    At first I tried with clips and barely worked, then I went all in and use the 3M double-sided adhesive, and I haven't looked back; I start printing and either leave to do anything else or even leave it printing over night.

    Now, after a couple of corner issues I followed the recommendation from Jeff at the reprap wiki (http://reprap.org/wiki/PEI) and bought an 800 sandpaper and sanded the whole printed area covered by PEI. Issues solved. Attached a couple of images so you can see the bed and how is the bottom of the 3d printed pieces. BTW, the white stuff is from the sanded PEI plastic, you can even see the 3M double-sided adhesive sticking out of the PEI.

    IMG_8781.JPG IMG_8783.JPG
     
  8. regor

    regor Member

    Joined:
    May 20, 2015
    Messages:
    51
    Likes Received:
    6
    Robo R1 has auto leveling. Do you have to do any compensation in the firmware for this extra PEI being placed on the heated bed?
     
  9. Terry Reilley

    Terry Reilley Member

    Joined:
    Dec 21, 2015
    Messages:
    104
    Likes Received:
    20
    OK, so here's another issue for the day I'd like to share:

    I bought and installed a sheet of PEI on my chipped bed about 3 weeks ago. I'm a casual printer, so I don't run it all day every day. A few days ago, some of you know I was struggling with prints not sticking while using S3D and I adjusted my Z offset accordingly. Now they are sticking so well that I can't get them off, lol. And this is whether I use S3D or MatterControl, so I know it's not the software - it's the inept user.

    Maintenance-wise, I clean the PEI every few prints or so with the alcohol and have even sanded the bed with 800, then 1000, then 2000, but the prints refuse to come off (even after the bed is completely cold) without a lot of prying. Sometimes I just can't get an edge to get my tool under and so I say a few choice words and grab pliers. Pliers + PLA/ABS = disaster. It's pain to have to scrape skirts off too.

    I ran ABS at 235 and heated bed at 80, BTW, but PLA is sticking too.

    Does anyone have words of wisdom for the novice printer/inept user? I have a new glass bed I bought from Robo, but I like the PEI a lot when it it lets me have the print back.
     
  10. daniel871

    daniel871 Well-Known Member

    Joined:
    Apr 18, 2015
    Messages:
    1,322
    Likes Received:
    510
    Since the machine probes with the nozzle tip, no.

    As for the PEI really holding onto the parts, you have to decrease bed temps on tests with a material until you hit that sweet spot for a particular type of material where the PEI will let go when the heat comes off.

    Or you can fiddle with the Raft settings in S3D so that it only builds one directly under the part being printed while still allowing easy separation from the raft after pulling the whole thing off the PEI (working on the theory that a raft will be easier to slip a scraper into than a solid bottom piece of material).
     
    Terry Reilley likes this.
  11. jediknight0

    jediknight0 Active Member

    Joined:
    May 22, 2015
    Messages:
    110
    Likes Received:
    25
    I find these discussions really interesting... I've never had a problem getting my parts off the PEI bed... and I still have trouble with ABS parts warping a bit. Don't get me wrong, the PEI is better than anything else I've tried, but there's no perfect answer yet.

    bare bed < painters tape < painters tape wiped with alcohol < purple glue stick < PEI

    Parts adhere better if I heavily squash the first layer, but then I have to deal with bad elephant foot. Even then, once the bed cools down to about 50 (I print between 100 & 105) I can convince the parts to come off with just my hands.
     
    mark tomlinson likes this.
  12. Terry Reilley

    Terry Reilley Member

    Joined:
    Dec 21, 2015
    Messages:
    104
    Likes Received:
    20
    At first,the parts popped off with no effort whatsoever after cooling off and that was less than 3 weeks ago. My initial thought was that I had something set in S3D after adjusting the z offset to resolve the filament NOT sticking enough so that the filament won't release now, but the problem persists in MC. I agree with Daniel871 that there must be a sweet spot and I'm just going to have to find it again. It's crazy that I've been printing pretty successfully up until now and suddenly everything seems to be going wrong. The good news is that by the time I resolve all these and hardware issues, I will feel comfortable building a printer at some point, LOL.

    Here's another interesting point - I can see ripples in the PEI sheet now if I look along the Y axis in the right light. I can also feel it slightly when I wipe the bed down with IPA. I used a solid sheet of the 3M adhesive, so I suspect the combination of heat and aggressive removal may have had some kind of effect on that.

    Oh, and I ordered Mike Kelly's enclosure so maybe this will help in a big way with the ABS that I'm dumb enough to keep using for my 501st printing. I wish I had done my E11 blaster in PLA now, but I really liked the idea of smoothing the prints with acetone (yeah, about that...).
     
  13. jediknight0

    jediknight0 Active Member

    Joined:
    May 22, 2015
    Messages:
    110
    Likes Received:
    25
    I've had the same experience... with glue stick. Parts were working pretty well and then stopped sticking very well at all. That's what got me to make the jump to PEI. I've (somewhat) concluded it's related to time of year... it's naturally more humid in winter so I'm thinking the humidity in the air is affecting my ABS.


    I also see that. It's definitely the heat causing little 'pillows' in the PEI sheet. The first time I attached the sheet, I had a lot of them. I removed the sheet, cleaned the bed, and re-attached and it was better... but now I see them starting to return. I know sometime soon I'll need to re-apply the PEI again.


    Yes, that's why I use ABS. Recently I've been printing stuff for the bathroom (toothbrush holders, shower speaker holders, etc.) and the ability to have a smooth surface to wipe clean is more important than the loss of detail or difficulty.

    For an enclosure, if the parts are not too big you can do what I do - Use aluminum foil and tape to create a poor man's enclosured chamber.
     
  14. regor

    regor Member

    Joined:
    May 20, 2015
    Messages:
    51
    Likes Received:
    6
    I'm really a PETG filament lover and with PEI on the glass bed caused me great difficulty in removing my prints, they would stick like glue. Kept lowering my bed temperature, now finally found my sweet spot of 40 C for the bed and 245 C for my E3D V6. Before this I would find small pieces would strip a small spot under the print or I would actually break them trying to unstick them.
     
  15. Multitech

    Multitech New Member

    Joined:
    Sep 12, 2014
    Messages:
    17
    Likes Received:
    0
    late to this party...I printed once or twice before re-calibrating, however as daniel871 said, no, no especial configuration. Nonetheless i did actually re-calibrate the leveling for peace of mind, but since it does have auto-leveling then I doubt it has any impact.
     
  16. Multitech

    Multitech New Member

    Joined:
    Sep 12, 2014
    Messages:
    17
    Likes Received:
    0
    I have not printed any other material than ABS since I got the PEI, and as everyone else is saying here I had to look for the bed's temp sweet spot, for me on ABS it was 105; the prints stick really well and I usually let it cool down to around 40 before attempting to get the parts off of the bed. They do stick really well and have to do it slowly otherwise I feel breaking the glass, but I have yet to experience any warping.
     
  17. jsam

    jsam New Member

    Joined:
    Aug 15, 2016
    Messages:
    24
    Likes Received:
    4
    Hi guys, I just did this upgrade to my Robo and won't get a chance to print until this weekend. I was wondering about the autoleveling sequence the Robo does after the hotend is up to temperature. Will the heated nozzle damage/make a divet in the PEI surface?
    I'm printing PLA at the 210 and the melting point of PEI appears to be between 204-232.
     
  18. danzca6

    danzca6 Well-Known Member

    Joined:
    Jul 27, 2015
    Messages:
    2,161
    Likes Received:
    1,074
    You may want to adjust your start gcode to not heat the nozzle until after the G29.
     
    mark tomlinson likes this.
  19. Multitech

    Multitech New Member

    Joined:
    Sep 12, 2014
    Messages:
    17
    Likes Received:
    0
    No issues on my side, so far...I didn't change anything on the nozzle settings, and I haven't experienced any melting of the PEI. After autoleveling the nozzle touches the material but it is really too fast to create any damage or melt it.
     

Share This Page