eldrick

I received my QR 3.0 yesterday. It's nicely made, and sturdy as it gets. Spent the rest of the day printing an adapter plate to mount it on my UM2, to move the feeder to the left of the printer. The point is to make it possible to feed from the left side of the machine, as well as the OEM spoolholder on the back. I prefer to keep an eye on the filament during long prints, and it's a lot easier to load filament from the left side. I posted the adapter design to youmagine: https://www.youmagine.com/designs/bondtech-qr-adapter-for-um2

duplicate - removed

Just out of curiosity, who is responsible for the horrible system of dot-marking? I find it hard to imagine any way to create more confusion than by not only using a random number of dots for the sizes, but also completely changing the system more than once over less than two years. That's just insane.

DiamondAge is absolutely the best PLA available. It is monochiral, and very hard. However, it's not available here in US, due to having had a terrible distributor. I've recently been buying from MakerGeeks - their Clear (Natural) PLA is less cloudy and tinted than other vendors, and their prices are about half. It's 2.90mm spec, and runs fine on my UM2.

Try printing cooler, so material does not ooze from the nozzle during motion.

Looking forward to it - I've been printing using the Fuzzy Skin feature on a sport-fencing product, for excellent grip in the hand.

Have you measured the filament diameter? I had similar results yesterday with some filament that was up in the 2.9+mm size. It causes variable friction in the mechanism.

The parts I want most are the replacements for the finger-ripper clips on the printbed.

Do you really think anyone will ever watch over seven minutes of a head moving? Also, the extruder could be lower-friction if you rotated it, so that the filament could feed back from the left side of the printer, putting the natural filament curl in line with the curve of the Bowden tube. I'm assuming that it would take a 35w or higher heater to deliver the increased speeds.

Has anyone done a geared feeder for the UM2, like the new one on the UM2+ ? (I'd prefer to avoid the belt-driven versions)

That looks like intermittent feed-friction issues - the random skinny lines. Have you measured the filament diameter? (UM2 needs 2.85mm, not 3.00mm) Have you checked that the filament feed path is low-drag? That would include free movement through the Bowden tube and the feeder, and having the filament feed from low on the left side of the machine rather than the back, so that the curl of the filament is in the same direction as the curve of the tube.

Got a recommendation for a board? (ease of HW/SW installation would be a priority)

The fan shroud by Izzy does not use ANY screws, and swivels out of the way when you want to clean the nozzle. Not much point in griping about something you can fix by using the printer...

The whole UM2 metal fan shroud is offal (sic). It is probably the worst single part on the UM2 - even worse than the feeder. It is noisy, it wastes a lot of air-flow, and what air it does move mostly goes to the wrong place anyway. I've printed a number of fan shrouds - IMHO, the most effective is by Izzy (search on youmagine).

I couldn't tell you, but it prints (slowly) at the max temp limit of a UM2. (it's been a while)

Total friction. You won't need numbers if you try it out - the difference is immediately obvious if you disengage the feeder drive cog and slide the filament into the tubing - much less friction.

I'm using Izzy's Version 1. Seeing some deformation of the left duct in ABS too. I may reprint in polycarbonate.

Print this one, and you won't need any screws to hold the fans in place. https://www.youmagine.com/designs/um2-fan-duct It's also one of the best fan duct designs. If necessary, print using Kisslicer to adjust using "Inset surface" to get a light press-fit with your fans.

Nevertheless, using a PTFE Bowden tube 8-12" longer than OEM will reduce friction considerably. Here's the stuff you want: http://www.amazon.com/gp/product/B00KJDE67G Also comes in 10" length.

This is the stuff you want: http://www.amazon.com/gp/product/B00ID7D96O Also available in 5-ft. length. When you replace it, a) taper the inside of the feeder end with a reamer to make filament insertion much easier, and, b) use 8" to 10" longer Bowden tube than the original - it makes less friction when printing at the right-front corner of the build plate.

Have you measured the filament diameter? You may have 3mm filament that is actually 3mm or slightly larger, and the varying diameter of the filament can cause variable friction in the Bowden tube and PTFE spacer, causing random under-extrusion. For the Ultimaker, you Must use filament that is 2.85mm, not 3.0 mm. Ask the vendor before you buy...

Gornnr - have you considered selling your modified Bowden 1.75mm tubes? I ask because the glue you used on the PTFE is costly, since it only comes in half-litre bottles.

I discovered that if the ducts hang a mm low like that, make sure the groove is snapped into the threaded rod, and then you can push it up a little and it will stay put. However, I'm also going to print another set so I can drill out the holes with a 3mm bit, instead of 3.125mm (1/8").

Once you have leveled the bed, you should seldom need to do so again. What does need adjustment occasionally is the nozzle height above the bed. The easiest and most accurate way to do this is to install Tinkergnome's upgrade firmware in the Ultimaker, because it offers a menu item to adjust printhead height to zero. I believe that this is substantially more accurate than the OEM bed leveling, because it takes out the subjective measurement using paper as a feeler gauge; you just use the knob to lower the nozzle height at the center of the buildplate until it visibly touches the glass. And yes, the nozzle needs to be at the same distance for all sizes of nozzles.

dupe post - sorry