mostlyatomicbob

David, Have you had a play with the support settings? (goto expert setting) I usually use 'line' supports as they are much easier to remove, but they are not a stable as the grid. It looks like you need more support try adjusting the percentage of support up to 30% this will mean the extruding plastic has less distant to bridge when printing the first layer over the support. Finally i set the 'Z' offset the same as the layer height i am printing at. for example if I print at 0.1mm layers the Z offset is the same. I hope this helps Bob

'atomic method' I like that! Now I have not used woodfill yet but I wonder if you heated up the nozzle to 200deg C and then tried pushing regular PLA in to the hotend, then set to cool to 90 deg C. whilst it is cooling use an acupuncture needle or 0.3mm drill and push up through the nozzle. I wonder if doing this you will push up the blockage and that will get caught in the melted PLA. when the PLA is removed at 80-90deg C it should pull out the offending junk. It is worth a try, but give a few goes, as it can take 3+ attempts to clean a blocked nozzle with regular PLA so I would have thought it will take more to clean out wood fill. Bob

Mariem, Let the heated bed cool to room temperature and gently tap it from one side. If that fails pop the glass bed in the refridgerator for 10 mins and then it will just pop off.

The rear fan is supposed to run all the time. Don't worry this is totally normal. The fan is there to stop help the heat sink and stop heat from the hot end 'creeping' up and causing issues. If the fan isn't working you should switch the machine off!

Where i work we have 2xUM2, 1 UM Original, 1xRep 2 and 1xMakerbot Gen 5. The UM2 is the best in terms for general printing and the heated bed is a god send. the UM original still has the best quality prints on small items IMO. The Makerbots don't even come close...........

I have been using fusion recently and for the most part it is very good for modelling and exporting to .stl. However it is very unstable and does have a habit of crashing. cmd_s is your friend there. I have gotten into the habit of saving very frequently. I haven't tried importing stl's yet but i might give it a go.

I have not tried Spectrum, but I can vouch for Faberdashery's PLA it is very very good and the colours have to be printed to believe how good they are. I have also had a good experience with Colorfabb PLA/PHA and I have 4x2Kg under my desk as i write as I am fed up of running out of it!

GR5, a bit of both really, the file i was having troubles with is now all sorted thanks. Daid, No worries, taking all things into account I am very happy to leave my UM2 alone, well apart from the feeding issues, but thats another matter (which I know will be sorted soon)

Thanks fellas, Mucking about with the g-code scare the willies out of me! I guess I will have to start looking at scaling my models. If PLA does shrink around 0.3% that would be more or less in line with the shrinkage I am getting. Thanks for your help. Bob

Good Afternoon fellow Ultimakers, I have a question for the wise owls out there. I have been printing some fairly close tolerance parts on my UM2 but I am finding that they are not printing to the correct sizes. Now I expect some shrinkage from PLA but the dimensions are smaller than I would expect. On my UM Original i can set the 'steps per mm' on the Ulticontroller but I have had a look on the UM2 and I cannot find the same! Am I missing something? I don't really want to have to start scaling my models to compensate this deviation. Cheers Bob

Good work George. My problems appear solved. see here: http://umforum.ultimaker.com/index.php?/topic/4586-can-your-um2-printer-achieve-10mm3s-test-it-here/page-4&do=findComment&comment=39894

Aaron, I'm with you on the creep idea. I believe the glass temp of PTFE is about 120deg C. I am given to thinking that under normal printing this would not be such a problem but if the printer was left with no filament flowing through the hotend. For example when the nozzle gets clogged during a print. I am just theorising here, but it is a possibility.

Well my problem appears to be fixed. Ultimaker are sending me a replacement PTFE piece but I have a lot of work deadlines this week so I went and turned up my own replacement (the joys of a full propmakers workshop at my disposal!) and the results on the first test were flawless: Printed in Faberdashery Pearl at 230deg I have run another test to make sure it was not a one off, and again not a single skip from the extruder. However the question is how did the PTFE part get deformed in the first place?

A couple of marginally better photos:

gr5. Yeah the photo is a bit rubbish. The inner surface is deformed, it buckles inwards and outwards. When it is assembled with the hot end i can feed filament through but I can feel it catching. I think the problem maybe that when I am printing and the filament is retracting, the PLA is still soft and it forms into the deformation, then it jams into that shape. When I have been cleaning my nozzle i have noticed an extra blob on the filament that looks roughly like the shape of the deformation int the Teflon part. I will take a photo later. Out of interest is this part Teflon or PTFE? As i have access to a good lath and both materials, so it maybe fast for me to make one of these parts.

I use this stuff: It's very toxic, so must be used with care. It works on most plastics, ABS, Styrene, Acyrlic etc.

Thanks Woofy. But I think I might have found the root of my problem: The teflon part has a fairly large deformation which I am sure is inhibiting the flow of the PLA. I will open a support ticket and see if i can get a replacement

So, I printed this https://www.youmagine.com/designs/um2feeder-v3 over night on my trusty UM1. and here are my results: The print on the left was with the stock UM2 feeder mechanism, and on the right with the new 'improved' mechanism. not much difference really. I would be interested in being able to tweak the current to the extruder motor, but being a bit of a luddite i am not sure how to do this! Bob

Actually I did mean the first layer, the bed levelling is spot on (pro at that these days)! I read through a fair chunk of the Under extrusion thread and decided strip the hot end down. I removed a couple of burs from the PTFE and Bowden tube and I added a little chamfer to the inside diameter of the Bowden. This has helped massively. I can now print the above test but it starts to under extrude at 6mm/3/sec. Still work to be done but a lot better than at 9am this morning

I can push filament through the hotend by hand at 200deg with very little effort. I am pretty sure it is achieving the correct temperature. I'm fairly sure the problem is with the extruder stepper or the feeder mechanism. If i adjust the tensioner on the feeder to anything above the lowest position(lightest pressure) the motor just skips constantly. If i want to print anything ATM the first layer has to be about 230degs 20mm/sec and 90% flow and it still skips. After that If I have to print 0.1mm layers at 40mm sec but still get random skips throughout the print. When I first got the printer i was happily printing at 210-220 degrees, 60mm/sec, 0.2mm layers. With no problems what so ever.

So my UM2 can't even print the first layer without the feeder skipping. I have cleaned the nozzle out and the PLA is printing on my UM1 with no problem. (it's Faberdashery's Artic White) I am at my wit's end with this UM2 it is causing me nothing but grief. Strange thing is that when I first got the machine (early December) it was amazing and i was printing at 210 deg perfectly. As time has gone by I have had to print at higher and higher temperatures. I tried the test at 240 & 250 degrees and it still fails on the first to second layers. I guess I will try and print Takei's feeder on my trusty UM1 which is still working fine 11 months and thousands of print hours later. Bob

As it's Valentines day and I'm a cheapskate I have printed my wife a rose. Printed in Faberdashery colours.

The Ultimakers are made in Europe. So It's Metric all the way

Thanks Daid.

I would imagine the fuzz roller is to clean all the bits off the inside of the machine. I use a folded over piece of gaffa tape to pick up all the waste that collects under the bed.