Nicolinux

Ian's color sensitive bunnies seem to have taken over his keyboard because of their new http://umforum.ultimaker.com/index.php?/topic/467-post-your-latest-print/?p=37482. :mrgreen:

By the way. As a simple comparison. When I still had my Ultimaker Original, I printed the Twisted Gear Lamp (http://www.thingiverse.com/thing:31722) with the following settings - with zero underextrusion: layer height: 0.2 temperature: 215 speed: 100 Filament volume: 8mm^3/s.

No I am just trying to avoid underextrusion in normal prints. Some users proved they can print the extrusion test with stock settings (spool holder, ultimaker PLA, 230°) right up until 10mm^3/s.

Don't know. Asked Sander about a week ago and he said the teflon coupler is on its way. I'll ask again tomorrow.

I don't think so: It's hard to see, but underextrusion started at 6mm^3s. Printed at 230° and 90% flow.

Hey Sigi, what kind of filament is this? Looks awesome.

Ahhhh... neardgasm!

It will end up with your UM2 beeing called the "Bracelet machine" :grin:

Next thing to show your kids - the infamous stretchy bracelet (easy to print with spiralize and w/o top/bottom fill) http://www.thingiverse.com/thing:13505

Hey Aaron, my obeservation is that underextrusion occurs slightly after the extruder jumps back. Another seemingly related factoid I noticed while performing the extruder pulling force test (link) - the sound from the stepper changes its pitch when it is maxed out (e.g. before it slips back due to the weight). While printing I have never noticed this change in pitch (but this on the other hand might also be due to overall increased noise level).

Hey yellowshark. Thanks for the tipps. Did you add images to your post? Because if you did, they are not showing up.

Hi, just read about a new kind of plate that is designed to replace painters tape. Might not fit the UM1 print area, but it is an interesting concept anyway: http://3dprinterninja.com/ninja-printer-plates/

Waiting... my least developed character trait Personally, I don't believe that it is the extruder. This thing is strong enough. Something's wrong somwhere between bowden tube, teflon piece and nozzle. Or the board/stepper driver is broken and doesn't provide enough current at times. Looking at the last underextruded piece, the regular underextrusion pattern might indicate such a problem. Or maybe it is way less intricate and there is "only" some electrical interference due to a broken/damaged wire between the stepper and the board. Been there, done that. I now use an exquisite swiss_design™ filament spool holder (courtesy of Robert - link). But I still experience underextrusion (another hint that it is not the extruder in my case).

Hi, I am sure most of you print with different filament colors or types. Do you have some routines to share about how to test filament for its optimal printing speed and temperature? Also, since the bowden tube is quite sensitive about filament diameter, how do you measure it accurately? I wanted to create a generic gcode file with a simple object (something like Illuminarti's infamous extrusion test object - http://umforum.ultimaker.com/index.php?/topic/3976-almost-always-missing-layers-underextruding/?p=33427). So how are you doing it? Can you share some tips?

By the way would you like to share your filament test routine? I have started a new thread here: http://umforum.ultimaker.com/index.php?/topic/4432-filament-testing-routine/

Yes this might be. Already took off again. Using the stock feeder again.

Hey Ultimaker, any news on this?

Hey guys, I recognize the measurement of the nozzle tip isn't very accurate. I tried it this time with a needle. Inserted the sewing needle as far as it went and added a piece of tape to mark the point. Also tried to use a sharp pen to mark it. Depending on the marking method, I got 0.38mm to 0.40mm @3Dmaker4U: Cleaning the nozzle is very easy. Just undo the bowden tube (head), push a piece of filament through the nozzle while it is hot. Then wait until it cools down to 90° and pull it out. You'll get a nice nozzle tip shape and a clean nozzle: By the way. I printed the UM2 feeder in clear PLA, mounted it and printed the extrusion test again. For one this feeder produces some weird noise. Check out this vide (volume up) The extrusion test failed again (printed as usual at 230°): One thing was interesting though. The underextrusion patter at the top (I think at 7mm^3/s) looks very regular: So yeah, still waiting for the teflon coupler...

Hi, I have performed the extrusion/measurement task. Set the extrusion speed to 60mm/min in Pronterface. Temperature was set to 180°. I extruded several strands of 30mm. But while extruding the extrudder started skipping. This produced visible deformations on the extruded filament. It looked something like this: I measured in different locations and got between 4.8mm - 5.0mm (thickest) and 3.9mm - 4.2mm (thinnest). I also managed to take better™ photos of the nozzle. It won't get better than that with my iPhone (and skills...): EDIT: scale in mm

I will do this test. But I don't have a micrometer. Only a digital caliper but it should be accurate enough. Regarding filament, I don't have light blue. My UM2 was sent with silver grey because they were out of ultimate blue. Here's the filament I have (only stuff from Ultimaker): bronze orange green white pearl-white red silver-grey silver-metallic transparent Let's settle on orange. It is very bright and and provides a good contrast to the nozzle color.

All extrusion tests were performed at 230°. And yes, I had an UM1 but I sold it before ordering the UM2. I also deleted all Cura settings from my Mac. Given that other users printed with the same settings but with different outcomes, there's got to be something off. I also printed while holding the filament right below the extruder. This produced the best results so far. But after adjusting the knurled bolt I now get underextrusion right after the 3mm^3/s ring. I assume the extruder pushes now with full force (also repated the extruder pulling force test) so the problem must be further up (bowden tube or head/nozzle). By the way, anybody tried to print without the bowden tube? I'd like to remove just to rule out the possibility of a deformation inside the tube. But I imagine without the bowden, the filament would just bend upwards and not move into the head. Maybe if I guide it by hand during printing.

But that's just crazy. 30% difference for such a delicate precision part seems unbeliveable. But I want to know for sure. I'll try two things tomorrow. 1. I will try to take a photo with filament inserted into the nozzle to provide more contrast (like the first photo you posted). 2. I'll empty the nozzle, disassemble the head and take a photo at a straight angle through the nozzle. If I am lucky, the teflon part could arrive tomorrow.

But this would only detect problems inside the bowden tube. The extruder pulling force test did prove that it is strong enough. Nah, Ultimaker is not like this. These are the pains of a successful product launch and maybe quick growth of the company.

@hacklordsniper: You'd need to measure the force needed to extrude something and I don't know how one could measure it accurately. I am not aware of an official answer, only some scattered threads about it. By the way, just to rule out another source for this problem, I bought a cheap sd card and printed the extrusion test from it. Made no difference.

Thanks but the iPhone 5 cam is really bad for such a job. I can't get it to focus on the nozzle. I'll try again later today. Maybe I'll get lucky.