gr5

I don't understand the question. Do you want to change one of the core's during a print? Or do you want to change the nozzle on the core (not during a print)? The AA core is slightly better at not leaking. The BB core doesn't have a crack for the PVA to caramelize in.

Why did you stop the print? The pva looks fine. I'm not sure what I'm looking for. PVA doesn't print as beautifully as PLA but it should still be valuable support. Anyway if the PVA isn't working properly it's usually because you need to dry it. Set the print bed to 80C and put the PVA on the bed with a towel over it overnight. If your PVA is very wet you can hear it sizzling and popping while printing and sometimes see steam coming out and the PVA is snowy. But sometimes the PVA is only a little wet and it doesn't print well but you still don't hear any popping. Never leave PVA on the printer when not in use. I just lift the lever on the feeder and slide it out and then slide it back in for the next print. I keep my PVA in a 2 gallon (3 liter) resealable bag with lots of dessicant (around 300 grams dessicant which I have to bake every 2 months).

Look at the part in xray view - anything red is an error. That often shows the problem. There are many issues with sketchup as it lets you create non-manifold parts (non-solid parts) and infinitely thin walls (which are printed properly by not printing at all). Make sure all surfaces are white - any surface in sketchup that is gray - you right click on it and swap surfaces to make it white. That will make a big difference to cura as now cura knows the inside versus the outside of your seemingly random walls. Much more info here and this is easy reading: https://i.materialise.com/blog/3d-printing-with-sketchup/

It sounds like maybe the model is supposed to be hollow for the first 16 layers. Although maybe it's just a bad model. You can repair bad models most easily by passing them through the netfabb free repair service (you have to create an account): https://service.netfabb.com/login.php Or if you are lucky you can just go into Cura "mesh fixes" and play with each of those. One of those might fix the problem. But many of these will fill in areas that you want to be open so check carefully in layer view before printing.

Search for "support placement". Just above all the settings you can put a word or two and cura only shows matching settings.

Are you using PVA? You don't need pva for all those windows. Even the ones at the very top. PVA can create those holes. If those aren't pva holes then they might be due to speed changes. To fix PVA holes, block support where those windows are. The tops of the windows have a "bridge" and your printer can bridge pretty well. Especially such a short distance. A good example of a bridge would be the top of a door frame. More info here - look at the first two bridge photos here: https://support.3dverkstan.se/article/38-designing-for-3d-printing#span-instead-of-overhang To fix holes due to speed changes - get rid of speed changes. Change all your printing speeds to 30mm/sec and the quality of your print will go up drastically. Leave the bottom layer speed at 20mm/sec. Leave the travel speed at 150mm/sec (or faster). Anytime you have a speed change you get overextrusion or underextrusion because it takes a while for the pressure in the nozzle to stabilize.

What is the brand and model of your printer?

Did you read my post? Don't believe me? Here read this one: https://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#shifted Still don't believe me? prove it. Mark the pulleys and shafts with a sharpie and after you get a layer shift go back and check them all. Usually it's the pulley on the stepper that slips.

That should print fine. If it isn't then something is wrong with your printer. Maybe you are underextruding or have some play/backlash in the head. But to answer your question: infill overlap. Look that up. But really you shouldn't have to mess with infill overlap. Instead you should repair your printer. Or maybe you are printing too cold (too viscous) or too fast.

Please post pictures. Adhesion issues to the bed are solved here:

Well this puts gyroid on the outside. Or you could remove the walls altogether:

I think these are unrelated. The "too long to warm" issue is probably the head cable as you say. It's trivial to remove the rear two long screws in the head and pop off the rear of the head, reseat the connector, push a little cable in as you put the cover back on (and add some tape as a shim) and re-insert the two long screws. Takes about a minute. The switches are unrelated to the head. Push the head around and listen for "clicks". Then look to see what makes the click. Sometimes the X rod isn't hitting the Y limit switch when you push it to the rear - X rod needs to stick out a bit to the left to hit that switch. You might simply have to slide the X rod that goes through the head slightly to the left. Maybe only 4mm. Slide it so it hits the wall and then back off at least 1mm. Check the X switch also when the head moves to the left.

Are you a programmer? Are you familiar with web protocols? If you go to the ip address of your S5 (or UM3) and then click on the temperature link it shows the power usage of both cores and the bed. In a graph. You can look at the javascript code and write your own code to capture the raw numbers and analyze it any way you want. I'd love to see this data. Especially if there is a failure of some sort. I'm wondering if it's possible to determine that you have a nozzle clog due to the power usage (I know the filament sensor detects this also but maybe for the UM3?)

I strongly recommend you stick with the mark2. Much better tested. It works quite well. Maybe better than the UM3. And everytyhing you need to buy is available. On the downside it costs around 500 euros.

Cura is probably doing slightly more violent or faster moves than your other slicer but the printer should be fine with that. Most likely you have a loose pulley. Does your printer use belts and pulleys? If so tighten the hell out of the set screws on the pulleys. That's one of the most common problems that cause layer shifts like this.

It looks like the problem is only on the bottom layer. The bottom layer is extremely sensitive to "leveling" or how close the nozzle is to the bed when printing the bottom layer. It looks to me like your extruder is slipping occasionally and that is probably because you are just a little too close to the bed. Or maybe your extruder is a bit weak. Or the teeth in the extruder are a bit weak and the filament slips backwards occasionally. As a test, hold the filament while it is printing the bottom layer and feel for it moving backwards suddenly followed by these underextrusion spots on the bottom layer. The fix might be to level about 0.05mm farther from the bed. yes, one half of one tenth of one mm. 0.05mm. That might be enough.

You don't need to save the profile. Saving just the gcode works fine. flow is usually reflected in the extrusion numbers so if you look at the E value in the gcodes after the first layer is done you will see it's a higher value when you set ILF to 110%. 110% is so small it does almost nothing. Maybe try 150%? Personally I never miss with ILF and instead I mess with "leveling" or the distance between nozzle and glass while printing the bottom layer. You need a good amount of squish to get it to stick well but if you are too close you can get an ugly bottom layer where it squirts out occasionally/randomly. Not that I usually care too much.

First of all I would avoid the G91. You can reset the extruder to zero: G92 E0 But I wouldn't reset any other axis. You can still use the G1 E-2 Now why are you moving the Y to position 220? That's all the way to the rear? Would it be better to move Z to 220? I guess I need to see a photo of your particular printer. On the ultimaker printers, moving Z to 220 would make sense as that lowers the build plate down (the head doesn't move up and down on ultimaker printers). wait - you must have a bed that moves in Y. Okay I like this - slide the print forward to the front of the printer. Just don't do this G91 at all as it is probably what is causing you the problems. G92 is much safer. G91 probably has bugs.

@bagel-orb and @maht is there a way to get a copy of the executable for this? I have windows and linux so if you have a version that runs on either I would be grateful. I have a need. If I can get this to work I'll post a photo of the resulting print.

Make sure "travel optimization" is turned off. I think when this is on it will ignore "infill before walls". I could be wrong. But it won't help your print much. You have severe overhangs. You need some kind of support. You can design support columns into the design of the print or if you have a printer that does two filaments you could use dissolvable support. This is an extremely hard print for a 3d printer without dissolvable support.

My guess was also that PVA strings caused those holes. I'd look at the part before you submerged it (take a photo) and also you can look at cura layer view and see if that's where the pva nozzle first gets close to the part after switching to the pva core.

I'd have to know more about your part. I followed your link but I just don't quite get why it needs holes to do the epoxy coating. Why not just coat it even if it doesn't have holes? The strength of the part is mostly in the outer shell anyway. Anyway here are some ideas: Disable the wall completely (set wall thickness to 0 and probably top and bottom to 0). This way you only see the infill. You can do gyroad or a 3d pattern like cubes. To save time I usually tell people the opposite. Don't print any infill. It usually doesn't add much strength to the material - especially for these cylinders you showed. To save time I also strongly recommend a bigger nozzle. The 0.8mm nozzle prints 4X faster than the 0.4mm nozzle. I know this is a public printer but it only takes seconds to change nozzles. But to achieve these speeds you print twice as wide (0.8mm lines instead of 0.4) and twice as thick (around .0.3 to 0.5 thick layers instead of 0.1 to 0.2). DON'T try to get faster speeds by setting the "print speed" faster. Like someone else said you can set the infill to 50% in the TUNE menu while it's printing live. And you can play with that to get the effect you want (strength and holes). 2 hours is not a reasonable time limit by the way.

Oh and look all the "minimum" related retraction settings and make sure it will retract even if the gap is only 1mm or so and even if it did many retractions recently.

Turn off combing. This is probably your issue. It won't hop unless it "retracts" and it won't retract if combing is turned on (which it is by default). Combing is a little more complicated than this but all you need to know is: turn off combing.

Oh - and I'm guessing you had gaps because of something we call "underextrusion". It's not great to rely on that as lots of things can go wrong when you have it this severe - like grinding the filament enough such that the print fails because it can't extrude anymore. One solution is to raise the temperature. I've done many prints at 240C which works okay for PLA (quality goes down but it works). The higher temperature means lower viscosity so it flows more like water than honey.