gr5

http://gr5.org/unbricking/ y https://software.ultimaker.com/releases/firmware/9066/stable/5.3.0.20211003/um-restore-5.3.0.20211003.img y

These were fun - I did the cutter in tinkercad for a class I was teaching. Normally I never use tinkercad.

Oops. Nope. I did 2mm walls!!

flow You are misinterpreting the colors. If you read the key carefully it is showing mm^3/second. The amount isn't changing, the speed is slowing down. The default in cura I think is minimum layer time 5 seconds. Those thin walls can print very quickly (not much to print) so it slows down (as it should) to give the layer below more time to cool. gaps Regarding the gaps - ug - there are over 500 parameters now in cura. You mention nozzle width but that has no meaning in cura - line width is what matters. Type line width into the search parameters and try 0.5mm - the gaps will go away which is good but will it now make 2 passes? I don't know. 0.6mm walls I recommend 0.8mm walls. I'm really not an expert so I could easily be wrong, but if I remember right, the last cookie cutters I made, I used 0.8mm walls and 0.4 (or maybe 0.37?) line width and that was a good thickness to the cutter. You don't want it too flimsy. And the dough I was cutting was easy to cut with 0.8mm walls. I did double height cutters - it was some kind of dog. Let me see if I can find pictures...

I'm pretty sure it's not the firmware. The firmware is extremely reliable. So your part is definitely not skipping every other layer. It would be much more severe. Those holes are "underextruded" layers because the Z moved too far. Could you verify that each ridge is 0.3mm apart? If they are .6mm apart that would tell us that something is very much wrong. I'm going to look at the gcode again. Did you ever remove the 0.3mm layer height in the support section? That still bothers me. a lot! It's not good to have different layer heights in the same layers and if nothing else it seems to be doubly extruding the pva layers. I don't think this is your issue but it might be. I'll get back to you later. Too busy right now.

The short answer is that thin walls print much better in Cura beta arachne: https://github.com/Ultimaker/Cura/releases/tag/Arachne_engine_beta_2 It can do that trick where it only prints the walls once. It still might jump from one spot to another. To stop the jumping try turning off all infill. If you are making a cookie cutter some people do another trick to make the walls perfect. It's a bit of a hack. You make your cad model solid. For example for round cookies you model a cylinder. A solid cylinder. Then in cura you make the walls the same width as your nozzle with (e.g. you can do 1mm walls with a 0.4mm nozzle just fine). Then you disable infill, top and bottom skin. You can turn on brim for some strength. It's not a perfect solution. The cookie cutter may be weak. You can't do dual level cookie cutters (I love those) that cut on the outside and add impressions (like eyes) on the inside. But you get perfect walls. The jumping might be because the walls get slightly thinner in spots. Even if the walls are perfect in cad, when the model gets converted to triangles, now the walls vary in width slightly. I'm not sure what causes the jumping.

It looks like you are in USA so contact support@fbrc8.com or just buy this: https://fbrc8.com/collections/ultimaker-3-spare-parts/products/lifting-switch-pack-um3-um3x

It's MUCH easier to fiddle with line width. Just to learn. Only then go back and fiddle with your cad model.

In cura you can set horizontal expansion to 0.4 and it will thicken everything. This may mess up many things in a bad way. It won't affect vertical so a thin enough horizontal wall may be between 2 layer slices. The best way is to fix it in CAD - one wall at a time. So you can think about if it makes sense. 0.4mm is the minimum wall thickness if your line width is 0.4 and you have "print thin walls" checked. 0.8mm is the minimum wall thickness if you don't have that checked. For curved walls - after they are converted to triangles, some portions will be slightly thinner or thicker so you need a 10% or so margin.

Oh. Okay I was confused by the picture because I can't rotate it in 3D. I thought it was a dashed wall. Now I see it's diagonal skin. Also I realize now that it's yellow. Not the expected red. I'd play around with nozzle size just to see what happens. Set nozzle to 0.15mm just to see if you get red passes. Yellow is "skin". Not wall. Not infill (orange seems to be infill). So to get ready for a wall above, at some point it goes - hey there is a wall above me so I better print some skin here to support it. But then on the next layer it's like - oh - the wall is too thin. But "hey, there's something above me. So I better print some skin to support it". At least that's my guess as to what is going on. Basically your walls are too thin. I usually make my walls 0.9mm to be sure they will print. Even if they are just breakaway support walls. I might do dashed walls for 2 layers then solid walls and then dashed at the top so they break away easy.

Wow - great experiment. Okay so it's not the Z axis. Edit the gcode and try adding a T1 and T0 every other layer? I'm not certain but I think that will switch to the other core and then immediately back to the first core. Examine your working gcode used for the pva first to make sure it does indeed use T1 and T0. To get to the gcode you can either tell cura to save as gcode or you can rename the .ufp file to .zip and then open that and it's not too hard to find the gcode file inside there. Really it's probably best (easiest) to just export as gcode file instead of ufp. I guess another issue is temperature. It cools the non-active head while the other head is in use. But it waits until the head is back to temp so I don't see how this could be it but you could test T1 and T0 alone, and then if that looks fine add in the temperature changes (to the left head only) to see if that does it.

Make sure you have a good cable connection into the print head. Failures on the print head board alone can cause the UM3 to not boot up. It's very common for pulling forces to pull the connector right out of the print head (partially). There are 4 longs screws. Remove the rear 2 screws only and then a panel on the head comes off. Make sure the cables is pushed firmly into the connector (if you choose to remove the cable beware there is a clip holding it in place that needs to be squeezed). Actually, watch this video before doing anything: https://ultimakernasupport.zendesk.com/hc/en-us/articles/115004226246-Printhead Try powering up one more time. If that doesn't work, because it sounds like you had a "head flood" there can be much damage while removing all that plastic. I'd take the head all apart. check all the cabling. Try powering up with it disassembled but electrically connected. If that still doesn't work I'd order the PCB in the print head. It's not expensive and can be ordered separately from any reseller but for you I recommend igo3d. Alternatively if you have time (and not a lot of money) then I'd get the "olimex serial-cable-f" and if you know linux somewhat you can look at log files and see what code is giving you errors. This guide will tell you how to use the cable and at the bottom where to find some important log files. Google can also help you figure out why it isn't booting. For example one error might be bad blocks on the eMMC solid state drive. Or some driver on the USB bus. Or most likely the i2c code written in python (so you can read all the ultimaker written code including comments right on the UM3) is having trouble communicating with the print head.

There are rounding errors both in freecad and in cura. You need to either make those walls 0.41mm or change your line width in cura to slightly smaller (by about 0.01mm). A 0.4mm nozzle prints reasonably well from 0.33mm to 0.48mm - really it can print beyond that - for example from 0.3mm to 0.6

If you do it right you will be wondering how you will ever get the parts off the glass. You will be able to pick up the printer and swing it around by only lifting on the printed part.

Oh. Yeah. Those came loose. Do all the things I mentioned. You can see me doing them in this video which explains in more detail:

So if you play through on the preview screen you can see there isn't much difference in what is happening on those pva layers. Whether pva or not it does: left tower, then right tower, then moves up a level, continues right tower, then left tower then moves up a level (then repeats the left tower). So it does two layers in a row then switches to the other tower and does 2 in a row. Also when it starts the right tower it always starts in the same corner and starts with the inner walls, then the outer wall, then the infill. When repeating a layer it does the same thing. head play or alternatively belt play Okay - I just deleted this section. If it was this the pattern would only show on front/back and not the sides so am going to skip to my next theory because I can see in one of your photos that the pattern goes all the way around. z-axis play Another theory is that something is really off with the Z axis. When you only use one core, during most of the print, the bed only goes down. Never up. So backlash is less of an issue. But with two cores it has to move the bed down (away from the core) while it does the switch and then brings the bed back up. So if there is any play in the Z axis it will fall farther than normal (or less than normal) when it moves the bed down to switch layers. Normally z-axis play is caused by dirt on the Z screw but that usually gives you very irregular amounts of play so you get thicker and then thinner layers in a random pattern. Your pattern is very regular. I don't know how to diagnose and fix this. I would recommend replacing both the z screw and the z nut. And while it's apart I would check how well the 2 Z bearings slide on the 2 Z rods (does it get stuck? Does it slide smoothly?). A bad Z nut can definitely cause a LOT of z-axis play. I guess the best way to diagnose this would be to put a brick or hand-weight (something around 10 pounds/5 kilos) on the back of the bed. If the pattern gets much better than it's z-axis play. By the way PVA must be keep crazy dry. Buy some color changing dessicant (get a liter) and put 1/4 of that in some container with tiny holes and put that and your spool in the same huge ziplock. Never leave the PVA on the printer over night. If you do, you can recharge the filament on the print bed at 70C (but slightly above the bed spaced with some PVA as the spool itself can warp) with a towel over it overnight (or preferably for 2 days). 8 hours only dries the outer bit of the spool but if you only left it out in air for a day then you probably only "wrecked" the outer bit of the spool.

Even if you got rid of the walls, the infill "skin" pattern (typically diagonal) would not line up perfectly and there would still be a visible rectangle. This is basically impossible (or amazingly hard) to fix. But I have a hack solution for you. Create the "mm" logo as a separate stl and leave the part blank on the bottom. Then insert the mm logo as a "infill mesh" (actually it seems to be called "modify settings for overlaps"). This will get rid of that outer rectangle but it will probably give you more than one wall around your logo.

1) Is this a mac? (this is the most important question and not realated to answer #2 below but most people won't answer it) 2) Make super sure cura isn't running. On a PC do task manager, locate it and kill it. Then you can edit the cura.cfg file in the same folder as the cura.log file. In cura use the "help" menu to locate where that folder is. It's a small file and easy to read. Set the top and left window location to 0 and 0. Set the width and height of the window to 800 pixels or something that is larger but not larger than your monitor. The cura.log file is here: %APPDATA%\cura\<Cura version>\cura.log (Windows), or usually C:\Users\\<your username>\AppData\Roaming\cura\<Cura version>\cura.log $USER/Library/Application Support/cura/<Cura version>/cura.log (OSX) $USER/.local/share/cura/<Cura version>/cura.log (Ubuntu/Linux)

Oh - and a photo would help.

A photo would help. Getting things to stick requires temp, surface prep, squish, rounded corners. squish 90% of the time if it isn't sticking at all then you probably aren't leveling right. While it prints the bottom row push up and then down on the bed to see if either improve things. It may look like the filament is touching the bed but what you describe sounds like the filament is just barely above the bed. YOu want it will squished into the bed. temp For ABS you want the bed at about 110C. ABS starts to get soft at 99C and you need to be above that temp for the first mm or so of your print. Otherwise the corners are more likely to warp up off the bed. surface prep ABS is tricky - glue stick is probably not enough unless you wet a tissue and spread it around thin. Look up "abs glue" and make some or use hairspray (google it for 3d printing) or use magigoo (probably best option). Also make sure to clean off all the oils. I clean my beds about once every 200 prints or so removing all glue and oils (oils from my fingers) to get a fresh start. rounded corners That all helps the first layer but to keep the print on the bed throughout you may also need rounded corners. If you absolutely can't modify your model to have rounded corners then select the brim option in cura. Even with rounded corners, brim helps even more to hold down the corners onto the bed.

Thanks for posting the 3mf project file. I looked it over and sliced it in cura (had to uncheck the preference "automatically drop models to the build plate") and sliced it and it all makes sense (models and slicing agree with your pictures that have a thick pva infill layer). So the quick answer is you need to check enable prime tower setting. I'm not sure it is underextruded but while it is printing with the pva core the left core leaks a bit. After it is done with the right core and goes back to the left it is a bit emptied out and takes a bit of time to get back up to pressure. A prime tower's purpose is to get the pressure back up so your left core is primed with 1/10th second of when it starts printing with PLA again. I examined the gcodes in the web page gcode.ws and looked at extrusion amounts and the PLA extrusion is consistent throughout. So nothing wrong with the gcodes. However I noticed that the support overextrudes by 2X. I see you have layer height overall to 0.15 but the support layer height is 0.3mm. Somehow this confuses cura and it extrudes PVA as though layer height is 0.3mm (even though the support layer is still 0.15mm). So I would fix that as well.

No. Well, yes. In about 20 years it might be hard to find parts for it. There are tens of thousands of UM3's out there so it's a good business for a 3rd party if UM stops making any of the parts. Already you can get chinese knockoffs of things like all the parts in the print head (the most complex area?) and you could replace all the "brains" with something like a duet. The print cores for the UM3 are the same as their strongest selling model today (S5) and the same as on the S3 as well. And there are 3rd parties that make printcores (3dsolex.com). And used parts for UM3 will also get cheaper as time goes on. A bigger concern is that Ultimaker printers use 2.85mm (aka 3mm) filament which seems to be dying out. There are 2 standard sizes: 1.75mm, 3mm and right now every manufacturer of filament makes both sizes (except Prusa which is nothing special at this point). So that's not an issue - the issue is if you buy another 3d printer some day you will have to stock both sizes of filament. That is indeed a pain.

Which gcode? Is it M280? And for help building marlin (or I recommend tinkerMarlin) there are instructions here: https://community.ultimaker.com/topic/16856-how-to-build-marlin-the-way-tinkerghome-and-ultimaker-do-it-if-you-have-windows/

Just use "fast 0.8" and change layer height to 0.3 or 0.4. That's it. There's no magic in the profiles. You don't need to tweak 5 other parameters - simply increase layer height some more.

If it's still spinning then power cycle the printer. Go to the part where you can control the cores separately and heat the problem core to normal printing temperatures (200C for PLA). Remove the bowden on top of the print head (remove the clip, then press down on the outer collet while pulling up on the bowden. Try pulling the filament upwards out of the print core. If it is stuck then wait for it to heat up. Once the filament is out of the core try lifting the lever on the feeder (it's very strong - lift hard) and pull the filament out of the feeder downwards.