gr5

cura is mostly a slicer. It converts STL files to gcode files. I'm not sure if you can also use it to send a file through USB. You might want to try repetier host. I'm pretty sure it's free and probably does a better job than cura for sending files through USB to a printer: https://www.repetier.com/download-now/ Anyway to answer your question maybe change the filename to end with ".gcode". That might help. Like "myfile.gcode".

Not only should you not merge the models - you should only load one at a time as you are creating two separate prints, right? You want to print one in one color and then print the other in the other color. Two separate prints. That happen to print one on top of the other.

So there are two models, right? You merged them. I think you only want to merge them if you have a dual nozzle printer. You said you only had one extruder, right? So don't merge the models.

I agree that you probably have the same problem - scaling down the number of triangles in your STL should fix the problem. Could you upload your STL? I'd like to look at it in meshlab. How to reduce polygons: http://www.shapeways.com/tutorials/polygon_reduction_with_meshlab

@Ili - is it possible your power supply shut off for a 100ms and your printer rebooted? The behavior is quite different. Try turning on your printer and noting exactly what the screen looks like (take a pic). then when a print finishes, look at what the screen looks like. The power bricks these days are too smart. They have little computers in them and often will shut down briefly. If this is the problem you probably need a new power supply.

You click on the part. Click on the move tool on the left side. Now there are 3 arrows for moving in XYZ. On the left is a box. Just type in the number of mm to raise the part in the Z box.

I also have very very hard water. My dishwasher is encrusted with this white powder. Vinegar removes it. We clean the tea pot every month. Anyway I do a final clean of the glass with "glass plus". I have never felt a need to use distilled water for 3d printing purposes. I use it for my soldering iron sponge but for cleaning and drinking I use tap water.

Greg could do that also - do a "file" "save..." so @DrinkWater can see all the settings.

So in Cura if you slice the part exactly how you did it when you had a problem - then go to "file" and "save" it will save the model and also the printer settings (machine settings) and also the cura profile and also the changes to the profile (aka settings). It also saves if you scaled the part, moved the part, rotated the part. If you place multiple parts that's all saved also. All into a single file (extension is .3mf but it's not just a model). That way you can post it here and other people like Greg and print with the exact same settings or just change one thing and tell you the one thing they changed.

FYI - UM printers use the actual nozzle to probe so they need to be hot. Otherwise a tiny bit of plastic on the tip of the nozzle would mess up auto leveling. Anyway to answer your question - in Cura go to the machine settings. Machine settings are usually here: go to left side of screen in PREPARE mode. Click on your printer, then do "manage printers" then "machine settings" In there is start and end gcode. That's where you change the order. You want "M104" and "M140" which heat the nozzle and bed respectively but don't wait. Then you do M109 and M190 at the end (which wait for full temp to be achieved). More details on gcodes here: https://www.reprap.org/wiki/G-code

I'm not sure what I'm seeing. You have to also disable brim and support so it doesn't print the bottom few layers and you have to position the height. In the photo above you are on the scale tool. You don't want to scale. You want to set the Z position.

>Attaching screenshot of speed in Cura. Looks even. Of course the speed isn't changing in cura. What's more important is if the lines are equal length. If there are groups where the movement is shorter then it will likely slow down there.

I don't know much about the ender3 but it uses Marlin firmware and these types of printers (like Ultimaker printers) have typically either an 8 or 16 line gcode buffer. They have to plan the next 8 or 16 steps constantly as it's printing because if the very next gcode is a sharp corner the printer needs to be able to come to almost a complete stop without violating the acceleration criterea. So if there are too many points (say 1 every 0.1mm) then it will print slow. And then in areas where there are fewer points/gcodes the printer will speed up. Look at your sliced model in PREVIEW mode and step through the lines (horizontal slider - not vertical!!!) as they are being printed. In some places where your printer slows down - are there more points closer together? If so you may have to fix this in your CAD export step. Or you can import your model in meshlab to see what you CAD did and you can reduce the polygons a bit - maybe have the polygons at least 2mm across for the most part: http://www.shapeways.com/tutorials/polygon_reduction_with_meshlab Of course this doesn't completely explain why vase mode is better. Still - looking in PREVIEW mode should give you some hints as to the problem.

At first I thought you had the "triangle" issue (link below) but no after watching the video I think your part is being printed centered on position (0,0). This is a common problem and easy to fix. Delta printers (google it if you don't know what I mean) have (0,0) in the center of the print area and can go negative in X and Y. All the other printers (most printers) have (0,0) in the lower left corner (where you are printing) and all the coordinates are positive (no negative X or Y values). There is a checkbox you need to switch. go to left side of screen in PREPARE mode. Click on your printer, then do "manage printers" then "machine settings" In there is a checkbox about if (0,0) is in the center or not. It is not! Change that checkbox. >>>https://community.ultimaker.com/topic/31676-how-do-i-turn-off-this-initial-triangle/

Oh - I just saw you said "S3" in the subject. Active leveling should compensate for the glass being higher in the center. Hmm. WTH? Watch it level - when it's probing in the center is it touching the bed for a longer time than other areas? If so then there is probably a spring issue. Either the core spring is a bit weak or the springs in the bed are too stiff/tight.

Make sure none of the 4 long screws at the top of the head are loose. I removed the rear 2 to check the connector and forgot to put them in. I did a few prints like that! quality was worse. The head rocked quite a bit around that shorter bearing - like as you describe. Probably not your issue. You probably have normal "play". The glass is tempered and the way the glass is made it's higher in the center - I mean the original sheet which is a few meters wide probably. I think Ultimaker specifically gets glass cut only in the center to get the flattest possible tempered glass (I think it's a mistake to use tempered glass but that's another topic). Anyway as a result the glass tends to be higher down the middle front to back or sometimes more like just thicker in the center like a tiny mountain. So then when you level at the 3 screws what happens is the rear 2 corners tend to be quite a bit low and the center tends to be pretty close but a bit high. Check the glass while attached to the bed with a straight edge. If it's more than 0.3mm higher in the center you should maybe demand a new one from your reseller. This happens sometimes (people demand better glass) and it's kind of expected I think? But also note that it takes only an ounce (200 grams) of force to bend the corners of the glass up. Just the weight of the glass on a flat surface with some thin coins (dime?) will make it flat again. So for me I just bent the hell out of that aluminimum plate underneath until it made my glass flat. But then I realized the other side of that plate is a circuit board with easily damaged traces!!!! Oh no!! I was lucky though - no damage. 🙂

Oh that sucks! If the frame is trapezoidal then when you go to print a square you will get a trapezoid and when you go to print a circle you will get an ellipse. If the frame isn't flat in the vertical/Z direction and it's not just tilted but "saddle shaped" for example where 2 opposite corners are higher then the other 2 corners, then you won't be able to level the bed without bending it into the same saddle shape. If you are in USA (you mentioned inches) then contact fbrc8 and ask them how much for a top panel for a UM2+. Maybe some of the side panels as well. It won't likely be on their website but you can email them at support@fbrc8.com. To save time include your serial number of your printer in the email. But you can probably just bend everything back to square. I know people on this forum who were successful. Note that it's more important that the rods are all square (and basically all in the same plane or parallel to the same plane) than that the frame itself is square. Although it's probably almost the same thing.

Here's another way to do multi color prints with a single extruder:

Well the way you seem to be attempting to do it... Go to menu item "preferences" "configure cura..." Uncheck the box by "automatically drop models to the build plate". Now load your second STL that you want at 1mm. click on that part and on the left side use the tool that allows you to move your part around. In the Z box type in "1mm". Make sure support is disabled. Now you have a second gcode file - one for the base part and one for the second color part.

I looked at your model (it would have been better if you saved the whole project - "file" "save...") but anyway the hole in the model is very tiny - visually it looks like about 0.5mm in diameter. 3d printers print vertical holes about 0.4mm smaller than what the model shows. Which means - you will have no hole. You can either add 0.4mm to the CAD model (which is what I always do) or there is a new feature in cura - search for "horizontal", "holes", or "expansion". There is a way to make the holes larger. It may mess up other parts of your model -- well not this model -- but other models. Why does the printer do this? PLA acts like a liquid rubber band as it comes out of the nozzle because it shrinks in milliseconds (before it is solid) as it cools rapidly. So when it prints that hole the "rubber band" is pulling inwards and you get that vertical holes are all smaller than desired. It doesn't affect the first layer as much but that has a different problem because it is oversquishing. On purpose. So that the part sticks well.

Please show a screenshot of your part. Are you certain it needs brim at all? Most parts smaller than 60mm in X or Y don't need brim. I'm curious how sharp the corners are and how far apart and how much material in between pulling as it shrinks.

You don't need to disconnect cables to rotate the steppers. Worst case you can turn off the printer but usually that's not necessary.

Okay now as far as bowden tubes popping off - I guess I could use more information. This should not happen. Once it happens you should cut 1mm or so off the end of the bowden because inside the collet there are 4 blades that hold the bowden in place - they dig into the bowden. If you force the bowden out it will scrape the bowden and remove the outer layer and next time it's even easier to happen. Inspect the 4 blades and get new collets if they are damaged (I sell them very cheap if you are in USA). Then cut off about 2mm off the end of the bowden. Bowdens should not come out. You can normally pick up the machine by the bowden and swing it around your head. They should not come out. It means the pressure in the bowden is extreme. Maybe you are printing too fast (e.g. layers too thick) At least you know your feeder is working well if the bowden is coming out, lol. Try to not go over 5 cubic mm/sec (multiply line width X layer height X print speed (check all speeds including infill speeds) and keep that at or below 5 (for 0.4 nozzle double that for 0.6 and double again for 0.8 nozzle). The printer tops out around 10 or 15. Best to keep things well below the limit.

Wow! You are having a lot of problems. Please stick with it. These UM2 series printers are a very good product. I use my UM2 printers the most. I guess we need more specific information. Let's take the problems one at a time. The problem above - it's hard to diagnose with just one photo and it could be something leaking around the heater block but I think it's a head flood caused by a part coming loose: What happens is at some point while printing the part it is wider than tall and then comes loose from the bed. Then it gets dragged around the bed like a hockey puck and the filament is still spurting into the print. If you don't notice and an hour or more goes by you get something just like the photo. To fix, heat the nozzle 200C and walk away for 20 minutes. Come back with a heat gun or hair dryer and some metal tools (like needle nose pliers) and pick off bits at a time. Shouldn't take more than 20 minutes. You don't need to get it all. Be VERY careful around the wiring - consider just leaving it around the wiring. Do you have parts coming loose often? You need as a minimum to wash all your glass beds. They get finger oils on them and they get dust. I wash my glass about once per month. I show how I do this - it's a few steps - in the video below. If you have parts coming loose a lot you probably aren't leveling properly. Please watch my video if you have corners lifting/warping or parts coming loose - this will solve many of your issues (but not all):

If it's off by exactly 2X - is it seeming to overextrude a lot? It could be that your printer has a hardware problem where it is moving the Z axis half as much as it is supposed to. There is a jumper on many 3d printers to set the Z axis steps/mm. I think it's in the wrong position or maybe missing. This is one possibility.