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gadgetfreak

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Posts posted by gadgetfreak

  1. We received a second UM2 unit yesterday and I printed a little test piece fine after calibration.

    Then we needed two bigger models (house/architecture) taking around 8-10 hours to print. 30mm/s, 0.1mm layerheight.

    I didn't have too much time so I just started the print with the supplied Ultimaker silver PLA.

    On coming back the next day,I noticed that the feeder had stopped extruding, but the hotend was still hot and "printing". The model had come off of the platform and not much PLA had been extruded in totalt, just a few layers.

     

    Filament expanded In Bowden tube

    The filament closest to the hotend had expanded - I guess because of heat creeping up?

    I had a spare bowden so I quickly replaced it. This time I switched to Colorfabb white PLA/PHA (known good) and started the same model.

    This time I did some manual recalibration of the bed but it might have been to close to the bed still because the same thing happened again (but the part of the model was still on the bed).

    I think it stopped feeding in both cases because of pressure building up because the nozzle might have been too close to the bed (but I'm not sure).

    What worries me is the heat creep. Is it really normal that the filament expands so far up in the Bowden tube?

    Filament expanded In Bowden tubes

    It's very hard to get out. I managed to remove the filament from one of the Bowdens by using a small 1.5mm drill, drilling a few centimenters into it and using the power drill to pull it out.

    Closeup drill Bit T

    It's not uncommon for the feeding mechanism to stop feeded every once in a while due to dusty filament, improper bed level etc. But if the implications of it is that you get a Bowden blockage then I think that a couple of spares should be included with each new Ultimaker.

    Else people will get tired of 3D printing quickly and that would be sad.

     

  2. Today the heated bed did not want to get hot.

    There was no error but the bed never increased in temperature.

    We have one of the few pre-production units, but I think the construction is the same for the production units (for example, there is a strain relief installed).

    The root cause was that one of the cables has become loose in the heated bed connector.

    It was pretty easy to fix it, but I did have to remove the glass and unscrew the levelling screws and the strain relief to access the heated bed connector.

    Then after re-assembly of course a re-leveling of the platform. Now it works again :)

    I wonder whether this would be a common thing to happen or not. Did it happen to anyone else yet?

    Picture below.

    UM2 loose cable causing No heating

     

  3. Actually, the filament guide is very good to use even for single extrusion.

    When having fresh rolls that barely fit a spool they are helpful, as well as for very long prints when the a complete roll of filament is not perfectly rolled up.

    See this thread for more examples:

    http://umforum.ultimaker.com/index.php?/topic/3412-help-design-a-better-ultimaker-2-reel-holder/

    (Ultimaker started shipping it after I, Ian and others reported that is was really needed/useful).

    /Daniel

     

  4. What Robert is writing seems plausible. Glass usually is very flat but if this is a brand new standard Ultimaker it is not glass, but acrylic plastic. And they can be bent.

    Furthermore you should avoid printing directly on unheated beds, you can use painters tape like 3M 2090 instead.

    We might have a spare acrylic bed if you are in a hurry...we do not yet carry Ultimaker spare parts for purchase, but will soon since we are now official Swedish Ultimaker resellers :)

  5. Hi Trevox,

    I noticed you are based in Stockholm.

    We (3DVerkstan) are the official Colorfabb resellers in Sweden and I'd like to help you if possible.

    The XT is not available in green yet, might you have the ordinary transparent green?

    It sounds/looks like there might be underextrusion if you have the nozzle a little to close, but that's just a theory.

    Please give me a call on +46 708 980 985 and I'll see how I can help you.

    Cheers,

    Daniel

     

  6. The second suggestion from gr5 is what you need to do, re-adjusting the pulleys on both X and Y to make sure the belts are parallel to the frame. It is easier if you are two persons doing this.

    Do NOT try to open the slider blocks. They are not designed to be opened and I think they are difficult/almost impossible to close again.

    /Daniel

  7. Could you please explain what you mean by 'more maintenance/cleaning'? I'm going to print XT soon with a printer/hotend that has been used for PLA and PLA/PHA so far... I just would have swapped the filament as changing from one color to the other.... something wrong with that?

     

    Will you be able to print fine with XT?

    Sure, just you a little hotter temperature (230-240 degrees is usually fine, of course higher with higher print speed). We use 75C when we use the heated bed in UM2.

    Will you be able to just swap filament back to PLA or PLA/PHA and start printing?

    Yes, but you would want to make sure that as much as possible of the XT (it's a type of PET plastic) has been removed from the hotend/nozzle.

    By just using the "XT" temperature when swapping, you will be able to get most of it out and then start printing with PLA or PLA/PHA again. However, see below...

    Will you be able to make beautiful prints with PLA or PLA/PHA after having used XT (or ABS for that matter)?

    I think so, however see below...

    Will the hotend work as good as before running the XT/ABS in the same hotend?

    I highly doubt this. I think it's pretty hard to get all the residue out from the "other/hotter" plastic type.

    You might experience a slower "flow" and the occasional underextrusion that might come at an odd layer. Or a blockage.

    I think that most of the previous plastic type could be removed by some special purging routine, like disassembling the hotend and cleaning it out like described in other threads. But that is very time consuming.

    I think that if you stick to the same plastic base type you will have far better consistency in prints.

    (This is from our own experience, we just switch to a completely new nozzle after experiencing the above and now the flow is a lot easier than before)

    If we compare to plastic injection industry they have routines to clean out the barrel and screw when switching plastics, which also include different detergents and such.

    It would be very interesting so know how the Stratasys and other "high end" machines handle this. Does anyone know?

    I would expect they either limit the type of plastics used in an extruder or that they do have a switching/cleaning routine.

     

  8. That sounds promising!

    What filament did you try?

    I just found that Sanjay from E3D did an excellent comparison on Ninjaflex, FilaFlex and "Flexible Polyester 40D Shore", it's here:

    http://forums.reprap.org/read.php?1,269018

    A lot of good advice on how to print these types (example use constant speed troughout the print even for the first layer).

    He tested them on a Mendel 90 which if I understand correctly has the feeder mounted on the hotend so no real comparison to the Bowden/Ultimaker setup...

     

  9. Hi,

    A friend of mine recently designed and printed a really cool BMX grip on his Replicator 1 a couple of weeks ago: He needed to upgrade his extruder drive a little bit and print pretty slow, but it turned out great, and is extremely flexible and durable.

    https://www.youmagine.com/designs/bmx-grip-ninjaflex

    I have ordered som 3mm from Fenner Drives but it will not arrive for a long time...so I whether someone else has tested this in an Ultimaker Original or Ultimaker 2?

    I don't have too high hopes on the Ultimaker Original, but the drive system on Ultimaker 2 is a lot better. The challenge of course is that on the Ultimaker the feeder motor is at the back and the filament is very flexible and will have quite some resistance to overcome in the Bowden tube.

    Here is the Ninjaflex filament:

    http://www.fennerdrives.com/ninjaflex3dprinting/_/3d/

     

  10. Im based in the UK - will update my profile - apologies!

    Although I do keep my garage relatively clean, during the winter months it can get very cold outside, and considering my garage is not heated the temp can drop! I think in that case it would be best to keep my printer indoors ;)

    What this cleaning agent for the filament, and should one use it on a regular basis just to keep the nozzle in good shape??

    Is it advisable to remove the filament and store it in sealed bags, or a sealed container, if the printer isn't to be used for long periods then?

    Although the OP is talking about being away for months, how long a time period would you say one should remove the filament if the printer is unused? A week, a month, etc??

     

    3D printing is very sensitive to temperature changes in the environment. I strongly recommend printing in an indoor/office environment. I've had customers report a lot of problems with adhesion/curling and they believed it was the material, but in the end it was the cold environment (a garage). Once the weathe was warmer, there was no problem printing. Of course, it can also be too warm/humid but colder is a lot worse from what I've heard.

     

  11. 3mm PLA/PHA from Colorfabb works excellent in the UM2, we print with it daily (we're Swedish Colorfabb resellers).

    Colorfabb XT works really great as well, however as I recently wrote in another post - I think that to have really low maintenance and get consistent printing, you should not mix different types of plastic in the same hotend as it is hard to clean out the other type of plastic.

    I think it's fine to mix pure PLA with PLA/PHA (same base plastic). But do not use ABS, or Colorfabb XT in the same hotend unless you are prepared to do more maintenance/cleaning. Use another extruder or another printer for other materials if possible.

     

  12. Here's a good comparison:

    http://www.protoparadigm.com/blog/2013/01/the-difference-between-abs-and-pla-for-3d-printing/

    PLA is easier to print, does not smell, is environmentally friendly (not petroleum-based) and can give even finer detail.

    ABS is more difficult to works with and smells bad.

    ABS does have some benefits, mainly that it can withstand higher temperatures and that it can be vapor polished with acetone to produce a very shiny surface.

    Basically.

     

  13. If you stick to one type of plastic (PLA for example) I think you will have minimal risk of clogging. So you can use different colors as long as it's of the same type. (Don't switch back and forth between PLA and ABS for example).

    We've had clogging which occured after a failed printing with a type of PET plastic. We cleaned it manually for a couple of hours (the entire fan shroud had been filled with molten plastic...).

    Since then the printer has worked but not as well as before the clog.

    I now strongly believe that it's very difficult to get *all* plastic of a certain type of of the print head when cleaning it.

    We recently changed the nozzle part in our UM2 and now it prints really really nice again. Before that (after the big clog) we've had ok prints, but every once in a while it would underextrude for an odd layer or so.

    So, to minimize maintenance, use only one type of plastic!

    Regardless, for the future I think it would be good if Ultimaker (and all other brands) needs to focus on ease of maintenenace; for example replacing the nozzle should not have to take more than a few minutes. For example, the Kraken design where the nozzle inserts are not threaded would help a lot.

    In the future when we have multiple extruders, it might be wise to use different material types in each extruder.

     

  14. This is a strange issue. What filaments have you been using?

    Airflow working in correct direction?

    I can send you some free samples if you'd like and test same gcode from the same filament spools. And you can send me some of yours so I can test that.

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