johanw

Great tip! I had the same problem with weak springs, and washers fixed it very nicely. In the long run, though, the springs will likely need to be replaced, so it would be good to have some advice on where to find them.

Picking up on an old thread .. I had the same problem, followed your advice, and it did indeed stop the leaking. Thanks!

Just in case: Do you have the hot-end upgrade installed? That upgrade made a huge difference in my case, with a UM1 from mid-2012. I had recurrent problems with both filament plugs and nozzle clogging. After I replaced the hot end with the new version, this hasn't happened a single time, making the printing experience a lot more enjoyable.

I have this idea that I'd like to throw out to see whether anyone might take an interest: How about recording a concert, while it's happening, by feeding streaming sound to the printer? At the end of the show, you would have a representation of what went on as a (hopefully interesting) piece of plastic. It's essential that the "recording" should be done in real time. I don't know whether this has been done before. Anyone? (I.e., converting a waveform primarily into 2D movements, and then at select points making a Z step. No upfront planning allowed.)

PS. The problems with horizontal displacement certainly remain in the print. I would like to look into acceleration settings, as pm_dude suggested. (Requiring a firmware change? Will need to investigate that..)

Success! I made some very minor changes to the setup, and finally the print went through with all pillars intact. (I also tightened the belts on my UM1 a bit, but believe that that didn't make a lot of difference here.) Here's my settings in Cura, in case others would like to try a similar print. - Layer height: 0.2 mm (impatient) - Shell thickness: 0.8 mm - Top/bottom thickness: 0.8 mm - Fill: 10 % - Filament: off-white PLA, from Ultimaker, set to 2.90 mm diameter - Flow: 90% - Temperature: 190 C. (I tried 185 C, but 190 seems better) - Support: Raft, with air gap at 0 mm - Speed: Print speed 20 mm/s, Travel speed 150 mm/s - Combing: On - Retraction: On - Minimum travel 2 mm - Speed 40 mm, Distance 5 mm - Minimal extrusion before retracting 0.01 mm (i.e., always retract as you move from pillar to pillar) - Z hop when retracting: 0.2 mm (tried larger values for no discernible effect)

Yes, I feel I'm learning something here -- thanks a lot for the further suggestions. I will certainly try them out as soon as possible. This is helpful advice, easily tested on my machine. I thought the belts were ok, but I guess these pillars are much more revealing than the boxy things I've been printing before. Tbc.. (will look into the picture posting too)

Ok, here's an update after another attempt. I edited the model (which is not actually flawless, having lots of little holes etc.) in Tinkercad, to make the support beams a bit shorter. Then I changed to 0.2 mm layers and z-hop of 0.2 mm. Following pm_dude's advice, I put combing back on. Good news is, this printed with only a single support breaking off. Following the print inbetween cooking dinner, I even applied a little superglue to put that broken part back on, resulting in a molecule print that is at least usable for its chemistry teaching purpose. It will have to be painted in color, after all, so tiny errors are acceptable. However, I also had a surprise: - I cut out a detail of the model that looked particularly prone to failure, containing just four beam supports. The result was a really good print, with straight pillars and great detail. But, - printing the entire model, which has 40 support beams, many layers are displaced horizontally, giving really ragged edges and a much lower quality overall. It seems that my printer can't cope properly with precise repositioning when the extruder needs to move across a long distance. Surprisingly, the columns at the outer extremes of the print -- far left, far right, back, front -- are smooth and precise. The ones in the middle are ragged and rough. I'd of course appreciate any hints as to why this is happening (New images of the latest print + the detail cut-out with good quality, added to the album:)

Many thanks for these suggestions! Re. making the supports stick: I forgot to mention that I had already set the air gap to 0 here. I have tried using brim, but actually found that to be less sturdy than the raft. The brim comes out with just one layer, which isn't very solid. I agree that the 3D model here could really be improved. For one thing, the supports are much taller than necessary. Then again, that's the challenge As for the z-hop: My machine is from 2012, with no build plate upgrade, so indeed that might be a problem source -- imprecise repositioning in the vertical. As far as I can tell, the results are still somewhat better using z-hop than without. My hope is to find some sweet spot of settings that will allow for the print to go through. I'll try some variations and post updates I make any progress.

What are your experiences -- and recommended settings -- printing thin supports on the UM1? I'm trying to print a cellulose molecule from a model that has thin support beams: http://www.thingiverse.com/thing:301575 I feel I'm getting close. Many parts of the model come out with sufficient quality. However, after five tries I still can't quite get through the print. Some supports always get knocked over, resulting in lots of plastic spaghetti (see pictures). I've been reading the http://www.extrudable.me/2013/12/28/meshmixer-2-0-best-newcomer-in-a-supporting-role/. Seems like the UM2 is the machine of choice there. Is it worth trying to do similar things on the UM1? These are the settings I used for the print in the pictures, after some trial and error. - Layer height: 0.1 mm - Shell thickness: 0.8 mm - Filament: off-white PLA, from Ultimaker - Temperature: 190 C. (It's possible to print at 180 C, but then the filament is so sticky it hardly moves during retraction) - Speed: Print speed 20 mm/s, Travel speed 150 mm/s - Combing: Off - Retraction: On - Speed 40 mm, Distance 5 mm - Minimal extrusion before retracting 0.01 mm (i.e., always retract as you move from pillar to pillar) - Z hop when retracting: 0.1 mm (should this be increased, perhaps?) About the breaking pillars: They tend to break below the base, but sometimes they break somewhere higher up. I have checked that the model gives two circular passes for each layer. In fact, the quality of the pillars varies a lot, with some coming out really well and others full of warts. Clearly it would be possible to change the model here, to make the pillars more sturdy and so on. I still think it's worth trying to figure out how to make the print as it is. Looking at the result so far, many parts do come out really well. What do you think, can the UM1 handle this challenge? Maybe someone can spot what I'm missing?

Trying out the 14.05 versions on a Mac, USB printing. It appears that RC2 has communication problems that weren't there in RC1. For instance, the "upgrade firmware" dialog works as usual in RC1, but hangs with RC2.