gr5

That may be true. I thought nallath said it was coming out this week but maybe he meant a beta version only? I think somewhere nallath said the beta is already out and it should get released this week.

Another reason is it takes many hours and many prints to dial your printer in to get really good prints and as soon as you change materials all that effort doesn't apply to the new material. PLA is a bit easier to print so there's not as much to learn. To get good looking ABS prints you need a heated chamber.

I've seen some people recommend 260 for the heat phase of the atomic pull. I don't know why. For PLA 180c is plenty hot for that stage - the more important temperature is the low end temperature which varies depending on filament type and nozzle shape. If you leave ABS at 260C for a while it will get extra sticky/gunky and it's harder to get it out. "a while" being like 10 minutes should be plenty of time but 1 minute should be safe. But if you print cooler than 250C it's hard to get strong layer adhesion unless you keep the fans off. To make things worse about 1 in 10 temp sensors is off by 10C (could be either way). So it's tricky to get the right printing temp. There are many reasons not to switch a lot - the "leftover" in the bowden, feeder, and nozzle is only one of the reasons (some dust in the feeder can end up in the nozzle an hour after you switch). Another reason is that the higher temps of ABS make the white teflon isolator get softer and you won't care much with ABS but when you switch back to PLA the isolator is too soft and you can either get underextrusion or you can get clogs when the head cools down and some PLA flows into areas it shouldn't be and solidifies into a mushroom clog thing.

I posted the above issue on what I think is the right github issue tracker: https://github.com/Ultimaker/CuraEngine/issues/

@bagel-orb - feedrate of 2412 mm/sec? Strange.

What tinkergnome said. Click the "..." button next to "enable cooling fan" and you will see more settings.

STL files should be in mm. Make sure in netfabb that when you export to STL you do so in mm. If you don't you can just scale the object in Cura by clicking on it and putting in the correct scale factor. Usually you want to scale by either a factor of 10 100 1000 or 25.4 (25.4 is number of mm in an inch). Except you want it smaller so 1/10, 1/100, 1/1000 or 1/25.4.

Also check your feeder spring tension - it should be compressed when closed such that the spring is about 11mm long I believe (my UMO is a few years old and things have changed). Tight enough that you can see the diamond pattern in the filament.

These 2 videos at this site would be helpful: http://gr5.org/olsson/ It's not chewing through filament? Then you probably have a totally different, unrelated problem. Maybe printing too much volume too fast? Here are my recommended top speeds for .2mm layers (twice as fast for .1mm layers): 20mm/sec at 200C 30mm/sec at 210C 40mm/sec at 225C 50mm/sec at 240C The printer can do double these speeds but with huge difficulty and usually with a loss in part quality due to underextrusion. Different colors print best at quite different temperatures and due to imperfect temp sensors, some printers print 10C cool so use these values as an initial starting guideline and if you are still underextruding try raising the temp. But don't go over 240C with PLA.

I have air conditioning in the summer so the humidity isn't too extreme. In the winter it gets pretty dry - but never store your filament with for example a bowl of rice. It will get so dry it starts breaking up. I store my filament in large plastic boxes and when I open a new filament package I toss the desiccant packet into the box. I often leave a spool on a printer for a few weeks without changing it or putting the filament away but in general I try to keep filament boxed up. I really don't understand what makes filament brittle. I have many spools of filament from different manufacturers and it has only happened to me once so far. It might not be related to humidity and instead related to age. All I know is if you take a piece of unused filament and bend it you can feel the difference. Good filament should not break easily.

This is an old issue that should be fixed in the cura coming out this week.

@swordriff is an expert at this kind of thing.

Airflow should make it even worse as the bottom of the printer (under the bed) tends to stay at room temperature but if you heat that also you will need even more watts to keep the bed warm. I don't know why your bed isn't up to temp but it's probably fans related - when you start printing the fans come on and cool the glass. For ABS you don't need much fan - the older "abs" slicers kept the fan off 99% of the time and only turned them on for a few seconds during printing bridging or overhangs. Anyway I found enclosing the UMO very well - especially the sides - and letting the whole thing heat up to air temp at least 40C - makes it so the bed doesn't have as much trouble staying at 100 to 110C. Also put a box over the top (with large hole for the bowden).

ABS is much harder to print - you usually get very weak layer bonding and also it's common to have problems with the part not sticking to the glass. Also when you switch back to PLA it will really suck. I don't recommend switching very often but sticking with one material for all of your prints forever if possible. However many people switch back and forth but this adds more things you have to learn about if you switch often. The UM2 can print perfect ABS prints every time but there are some key things you need to know. If you print only ABS then I recommend getting the IPM coupler from 3dsolex.com otherwise your teflon isolator probably won't last more than 200 hours of printing. Anyway to get to your question - the filament on the left has insufficient spring tension. The filament on the right is perfect.

Your fan shroud is non-standard so you need to let Cura know this. It's very easy to do. In machine settings there are 4 numbers for distance from nozzle to each of the edges of your fan shroud. Set these up and then Cura will place your parts farther apart to avoid the fan shroud colliding with other parts. Alternatively you can just check the check box for "all-at-once" mode which keeps moving around into different menus but in the version you have it's probably under "tools" menu.

raz - please pick the "best reply" and mark it as so.

Speedy - well if the print head is hitting a side that's something specific that shouldn't happen. Printing off the left edge is "almost" normal and a different issue but the 2 things may be related. How is the homing procedure? It should tap lightly the X and Y switches twice. I'm worried that one of your switches isn't working. Can you run it 5 times in a row from the menu system and make sure that's working properly? There's 4 ways to assemble the print head - you can have the nozzle front-left front-right rear-left or rear-right. Which way is it assembled on your um2go? Is your glass centered in the clips? I pushed mine a few mm to the left so it doesn't print off the left edge.

How old is your printer? When the um2go first came out there was a firmware bug where it was printing a bit to the left. It's normal for 0,0 to be off the left edge but it should never actually print over there. You might want to load the firmware from cura 15.04 into your um2go. Now having the printer bash the right side seems very strange. But position 60mm should be much to the left of center - at least that part is normal - the head can travel farther than your max print size.

That noise - not sure what it is but it doesn't sound serious.

This looks like typical underextrusion. I don't know XT very well. I have seen printers that underextrude and if you cut the print speed in half and increase temp by 10C they still underextrude and the only solution is to increase flow. In your case I recommend printing a small 10mm by 10mm hollow box 50mm tall with no top/bottom and now infill (0% infill) and .8mm walls. Then watch it carefully while in TUNE menu. If it looks bad try setting speed to 50%. If still bad try raising temp by 10C. If still bad go back to original settings and start increasing flow. Flow takes 16 moves to take affect so when you change flow listen for the change in pitch in the feeder or the tick tick ticking to speed up. Try 110%, 125%, 150%, 200%. Take notes. I'm guessing you have one of those printers that inexplicably need higher flow.

Please explain why you want ultiboot. I dont' think you need it whatever it is. People have used plain old Arduino's with whatever boot loader they come with on the UMOs. You shouldn't ever have to mess with the bootloader and if you do, the boot loader created by the Arduino community is probably the preferred boot loader. So if you need a boot loader for a bricked Arduino then the Arduino community is probably your best resource. What country are you in dmolina? In USA Arduinos are very cheap - $16 includes shipping.

@jprochnow @memory556 and anyone else in the USA interested in 1.75 conversion. Please email me at thegr5store _at_ gmail.com I have some kits on the way to USA and I can give you more details. These are still "beta" testing kits.

UM did experiments with the MK7 feeder wheel and found that it had the best grip at first but that PLA got stuck in the cracks and didn't fall out very well. The knurled sleeve just worked much better and is self cleaning even though the grip isn't as good as the MK7 at first, the MK7 needs constant cleaning.

I watched your video and it looked like it homed perfectly - right when the nozzle hits the bed. Right? not 12mm from the bed. Can you please post the first 50 lines of your gcode file? In UMO settings it's very easy to put some bad gcodes in the "gcode start" settings that will do what you describe.

Looking at your photo again it says "less than 265C" or "<= 265C". So they are warning you to NEVER GO ABOVE 265C. And indeed I've created clogs in ABS around 255C because I printed too slow. I'm glad you like the IPM. It can go as cool as you want but will not work with PLA as PLA sticks to the IPM.