gr5

Note that the UMO is just as new as the UM2 and has many upgrades since it first came out. The best way to get cheap frame is to laser cut it or route it from a material like, diebond, or plastic. Maybe there is a makerspace or fablab near you that you can visit and have the pieces cut. Plus you can customize it with your own name on it or something. Maybe a "minion" version of the UMO. The 1.5.7 controller doesn't work with PT100 temp sensor so make sure you get a thermocouple instead - 10k to 100k style is best. Also there are 100 different temperature curves for even just the 100k thermocouples so I would get one from the reprap forums so you don't have to make your own version of marlin with your own thermistor table. They cost less than 1€ so why not get one with an existing table.

Move the bed up and down by hand and try to see if you can feel something at that point. Several people fixed this by removing the 2 vertical bearings that are screwed to the bed and that slide up and down on the 8mm vertical rods. If there is too much oil on the vertical rods it can mess up those balls in those bearings. They need to be cleaned and dried and need no oil at all although one drop per rod shouldn't hurt anything.

Always look at layer view before you print. Although I guess you know that now. It will show you problems in 10 seconds instead of finding out 10 hours into a print. The 3rd photo with the red and blue - that's xray view - that tells it all. The red areas are problem areas. The color is determined by passing a line from the eye through the part. If it hits an even number of polygons it is blue or white or some shade in there. If it hits an odd number of sides it is a red shade. It means there is an internal wall. For example if you took two identical cubes and pushed them together but once together you removed one of the walls that are touching but not the other wall. That is what is happening. You can also get red if there is a hole in the object but I don't think solidworks can do that.

I don't recommend going with a smaller nozzle. It turns out your .4mm is a good size for this part. It's in the second tab, "advanced" but doesn't do anything if you don't also make the shell width a multiple of the new nozzle size. Instead you could just up the flow rate to 130%. you can play with that *while* it's printing to see the effect. Note that because the bottom layer is 3X thicker than the other layers the affect will be different on the bottom layer versus the other layers. You can set the bottom layer speed different but I would just slow it down in the TUNE menu from the prniter itself and watch for a difference. While you are debugging these things. Just set feedrate or speed or whatever it's called to about 30% and see if it helps (there is a delay of about 20 line segments). Then try other speeds and watch carefully. Maybe take notes. Same thing goes for adjusting the 3 leveling screws or adjusting flow rate.

>PS - Why are my keystrokes delayed when responding? I *hate* that - it gets worse and worse the longer the message.

I agree. I was wrong. It's all one part. I can see that especially the red path in the photo. 15% overlap should be plenty. If this was a UMO I would immediately suspect your belts are loose - look at the X and Y belts anyway. ALL 6 BELTS! Not just the 4 long belts but the 2 short ones also. But more likely this is not a backlash issue but instead an underextrusion issue. Try lowering the speed and increasing the nozzle temp. At that temp of 210C your bottom layer thickness of .3mm is too much for the extruder. Slow the printer down to 20mm/sec for that bottom layer and then you can go back to 50mm/sec for the rest. Also I hope your bed is at 60C - this will help with flow on the bottom layer. You might need to also adjust your leveling - the bottom layer traces should be flattened somewhat like a pancake and not round like string. DO NOT run the leveling procedure as you are already almost perfect - just twist the 3 knobs the same amount if the bottom traces are flat enough.

Damn it I should NEVER answer any question without a photo or video first. The problem is the part is not cooling enough - the head is keeping the part warm. The only reasonable solution is to print two "pencils" side by side so one has 3 seconds to cool while it prints the other. This will make a HUGE difference.

All PLA print about the same and are equally easy to get working. Learning a new material like nylon, pet, or ABS takes a while - maybe 100 prints - before you are getting perfect prints every time. I mean you might get something that is okay first try but e.g. with ABS you might have very weak parts with bad layer adhesion that seem fine until you break it and realize how damn weak it is. or it might string like crazy or every 4th print might pop off the bed or you might get nozzle clogs on every other print. PLA is the easiest and once you learn *any* material it is painful to switch.

It's best to show pictures but assuming the rudder was getting very small at the tip and nothing else was printing the problem is the PLA never has a chance to cool as the nozzle is touching it and it turns into a blob. The solution is to print a little tower the same height or taller than the rudder. I recommend a cuboid with the base length at least 1/5 the height. e.g. 10mm X 10mm X 50mm tall. Or 20mm X 20mm X 100mm tall. It can by pyramid shaped if you want to save even more time and filament. The purpose of the wide base is so it won't fall over right when the print is almost done and then ruin everything. Also place the tower near the tail fin so the fans are cooling the fin somewhat while printing the tower.

Although I don't think those pumpkin bumps had anything to do with retraction - you just get better quality at lower speeds. That was a UMO that had loose belts but still I get much better quality at 35mm/sec than 50 or 60. Your nozzle is blurry but it looks fine to me. I can see it has a complete ring that is about the same width as the nozzle hole. In other words nozzle shoulder is 3X diameter of nozzle hole which is normal.

Slow it down to 35mm/sec:

Let us know what prices you find for the 40W versus a 39W at my store (I currently have 36W, 37W, 38W, and 39W heaters - the latest batch was all a bit high - they were supposed to be 35W - last batch was low). http://gr5.org/store/ If they are as good quality and cheaper then maybe I'll stop buying them from Carl. Sorry Carl. If your material is balling up on the print bed it is either underextruding or more often you aren't leveled quite right - ignore the leveling procedure and turn all 3 leveling screws counter clockwise (as seen from below) by at least a half turn to get the glass closer to the nozzle. Do this while it's printing the bottom layer.

The latest Olsson blocks try to keep you from putting the temp sensor in so far that you'll never get it out again. That's normal. Also the temperature is sensitive to how far in the temp sensor is in. So if it's say 5mm further out of the block than a normal block it will read about 3-5C cooler and your head will be about 3-5C hotter than with your UM block. I know this because I calibrate and test every temp sensor that I sell in my store at 260C and it matters how far into my test block I push the temp sensor.

Your link doesn't work but all PT100 sensors should have the exact same temperature versus resistance curve. Unlike thermocouples which every manufacturer has different specs for. Calibration is trivial anyway - I always print now with bed at 60C - sensor is on the edge so the center of the glass is actually 65C (edges always cooler). This measured with an IR temp sensor which works very well on glass (glass is pretty opaque/black in IR temps). So just figure out what temp you have to set the printer to to get 65C on the center of the glass and make that your bed temp for PLA. Repeat for any other materials.

Yes. That.

I was hoping for the profile for the car at the top photo. If you still have the gcode you can do "load profile from gcode" and then save out the profile to an ini file. Anyway a few things popped out at me: retraction_hop = 0,075 This alone could be the problem. I've never used hop on retraction as I'm told it causes stringing. It's recommended only for delta printers I believe. The only other thing is some of the parameters I don't recognize and I'm wondering if you are using the beta version of Cura - all versions after 15.4.* are now labelled Beta and not recommended except for experimenting. Nyon - well nylon is definitely harder to print. I get much more oozing with nylon than normal. You really need to bake it in the oven for an hour just before you print with it as it absorbs water quickly. You probably hear it sizzling as it prints - that's the water boiling. More details I believe on the taulman website. Or maybe I read it somewhere else. I found that I can usually not preheat the nylon if I use taulman bridge and print it a bit cooler. But other nylons (most nylons) need to be dried right up until the moment of printing if you want good quality.

As far as I know there is no printer on the market that is more reliable. I talk to lots of people with lots of other printers and the UM *seems* to be the easiest to get working smoothly (at least printers that cost < $10,000). But I agree it could be much better. Lots of people have lots of problems. Not me.

Marlin is an open source firmware for 3d printers in general and runs on Arduino computers. The UMO uses the standard Marlin, identical to Marlin for dozens of other companies 3d printers. The main author of Marlin used to be Erik Zalm but now he works for Ultimaker. Go figure. The UM2 uses a special fork of marlin edited by "Daid" because the display on the UM2 is non-standard. The "tinker" version of Marlin is for UM2 products only and is edited by "tinkerGnome". If the official UM2 Marlin gets an update, tinkerGnome does a "git pull" which pulls in all the latest features and bugfixes automatically so the tinkerGnome version is usually at the latest version (or even sometimes has unreleased fixes as Daid is slow to send out new versions of UM2 Marlin embedded in Cura (Cura comes with some recent version of Marlin but usually it's an old version - sometimes a year old). Marlin is pretty stable and lately it's been rare that Daid makes an edit - maybe 5 per year? That's VERY rough. The official Marlin which works on dozens of printers including UMO gets edits almost every week. Tinker Marlin gets updates almost every week. Tinker Marlin is superior in every way and even has a "classic" mode so you don't have to learn the new menus.

I can see that cura is putting a shell around the outside of the bottom piece. This means Cura thinks these are 2 different pieces. OpenCAD or openSCAD? Anyway you need to make this into one piece somehow - delete all the walls that seperate the lower part from the upper part. This is a CAD issue. Alternatively you could try "fix horrible A" or "fix horrible B" in expert settings - look at it in slice view and make sure Cura is not putting a shell pass (red line) separating the lower portion from the upper portin.

If you make many of these then I would open it out and print it flat first, then put it in hot water for a minute and then wrap it around a pre-built wooden mold/cylinder. I did that recently with a halloween mask conformed to my face. You want the water around 60C to 80C.

I recommend you download tinker version of Marlin which lets you continue a print even the next day. I don't know what is causing your problem but I don't think it's file size as the printer only reads in a tiny piece of the file at a time. You could check the file on the SD card as sometimes people remove the card before the file is done writing. Use a diff program to make sure it matches what is on your computer. Anyway get tinker Marlin here: https://github.com/TinkerGnome/Ultimaker2Marlin/releases tinkerGnome marlin discussion https://ultimaker.com/en/community/view/7436-more-information-during-print

I see your minimum extrusion is .02mm - that's of 2.85mm diameter filament. That might be too large - it might not be retracting - so first thing to check is to look at those towers in layer view. Retraction is shown as a vertical blue line. If you have vertical blue lines leaving every tower then the .02mm is fine. If not lower that but beware that too many retractions (e.g. 100 retractions on the same spot on the filament) can grind down the filament to dust and cause failures. The other thing is that this is white filament. White filament makes strings like this more than any other color. It doesn't seem to matter who the manufacturer is. also 100 mm/sec is going to cause more stringing. This is because you have higher pressures in the nozzle. I recommend maybe 35mm/sec for these towers with 200mm/sec move speed between towers. But of all the recommendations - the most important is use a different color.

Generally the more flexible a material is (think rubber) the more it grips. If you want it to slide nicely you usually want a hard material (like steel ball bearings). Nylon is not very hard. It may slide well on wood - I don't know - but I think PLA and ABS are probably the best as they are quite hard compared to Nylon, PET, etc. It would help to polish them smooth or at least make sure the "grain" runs in the same direction as the movement. Taulman Bridge is probalby the easiest to print of all Nylons so I recommend trying just that one. It's relatively flexible though compared to some of the other Taulman nylons.

Could you just save your profile settings to an ini file and then just cut and paste the entire ini file here please? I want to look at every one of your 100 or so settings. The 200mm/sec is fine. I have seen these little strings before but they are rare - I've never seen so many on one part. You could indeed look at your nozzle tip - I recommend using a cell phone to take a picture as those usually are good at close up photography.

Did you try another color filament? I'm pretty sure that will fix your problem.