GregValiant

I see the Z numbers in the file match what you saw on the LCD. The numbers I posted above were off the top of my head. The numbers from the file are: Layer 18 at 3.9 Layer 19 at 4.1 ;Pause before layer 20 Repeat Layer 18 at 4.3 Repeat Layer 19 at 4.1 Layer 20 at 4.3 Layer 21 at 4.5 Maybe a moderator can comment on that. It's not making a lot of sense to me. Regarding the flow - the numbers you entered into Cura (114%) are used to calculate the E values that Cura put into the Gcode file. So the E values are already at 114%. When you manually add an M221 you will be changing those 114% values so go with the M221 S115 and then bring it back down with M221 S100. I get good adhesion from PETG and PLA doing that even when the top surface cools down when I'm slow to get the printer started again. Not to knock your design there, but I'd put a slot from the front ring to the tail hook attachment point. You could wire them together and it would be a lot stronger than trusting the plastic to keep a strike from tearing out the hook.

It doesn't work that way. Cura will not allow itself or the plugin to crash into a part and it appears you want it to go where plastic has already been placed. That qualifies as a Bad Thing because there just isn't anywhere for the plastic to go, and the head might move the print. What the redo does is repeat the layers but continuing upwards. (Cura layers start at 1 and Gcode layers start at 0. The numbers below are Gcode layer numbers.) Layer 18 at 3.9 Layer 19 at 4.1 ;Pause before layer 20 Repeat Layer 18 at 4.3 Repeat Layer 19 at 4.5 Layer 20 at 4.7 Layer 21 at 4.9 etc. I haven't used the redo. Instead, I hand code an M221 S110 when the print resumes and increase the flow for the first layer after the pause. The 2nd layer after the pause gets an M221 S100 to return the flowrate back to 100%.

At the top right of Cura click on Marketplace / Installed and then scroll down and make sure "USB Printing" is enabled. When Cura starts it will open the USB port to the printer. The port must be open to update the firmware as well as to print from Cura.

Well, there have been no suggestions so I ordered a replacement hot end fan. My current theory (theory #41a) is that some strings have wound around the shaft of the fan rotor and it isn't putting out what it should. I arrived at this theory because everything besides the fan has already been replaced. I ordered a Delta 4015 and will put a 1/8" spacer behind the metal cover to move it outboard 3.2mm. That should allow the 12cfm fan to fit inside. Theory #41b states that Creality put all the cheapest stuff they could get away with in the machine along with cutting the physical requirements as close as they could. I figure you can't over-cool the hot end. If 80% more air doesn't cure the problem I'm gonna design a dry ice system.

Put a "Pause at Height" (or two) in the Gcode file. Make the pauses below where you would anticipate the clog. It's a stupid workaround but it would allow the model to finish. I have been working on this same problem on my Creality machine for 2 weeks and haven't come up with a solution yet.

I think that you have two problems to solve. One is the build surface size and the other is a problem with the model. The actual printable area is determined by a couple of things. Within Cura, go to "Monitor / {your printer} / Manage Printers / Machine Settings" and check that the build plate size is correct for your machine. It should be a rectangle 350 x 350 and "Origin at Center" should NOT be checked. On the printer LCD check the Home Offsets. I don't know for sure but they should be something like X=-10 Y=-10 Z=0. The printer can have two zero positions. One is the absolute machine zero that Auto-Home uses, and the other is a relative zero that is the position of the head when it is at the Home Offset position. When a Gcode file is read, it uses the home offset position as zero. It calculates MaxX and MaxY by adding the numbers (350 and 350 in your case) to the home offset. That means that when you send the print head to X175 Y175 the nozzle should be dead nuts in the middle of the build surface. If it isn't you'll need to adjust the Home Offsets. Regarding the model, the gaps between the members of the array don't matter. Cura understands that they are gaps. Your individual model (that you have arrayed) is the problem. You can try to slice one model (single member of the array) just as a test. I believe even one model won't slice because of internal issues. If Cura 4.6 puts polka dots on the model or highlights particular faces of the model then Cura will refuse to slice because of problems in the STL file. I think there is a Mesh Fixer plugin for Cura in the Marketplace but I have never used it. Hopefully somebody else here can point you in a direction to check that model.

When that G28 auto-home is processed by the printer, it sends the print head up against the three axis switches. That is 0 absolute. The printer does NOT know where the bed is though. If you hand level the bed, then it will be below absolute 0 and there is no way for the print head to hit it because the print head is hard against the Z switch and can't go any lower. I'm thinking there is something going on with the G29 Auto Bed Leveling command (that is executed right after auto-home) and that your bed is above absolute Z=0 when the print starts. Two problems - one mechanical and maybe a second one in the firmware or software or maybe even with the BLTouch gizmo. I would start by leveling the bed manually to insure the nozzle can't drag. There are Youtube videos galore on that. In Cura, check for a setting called "Bed Adhesion / Z Offset" and make sure it is 0. On the printer LCD, check the Home Offsets. X and Y will be smallish negative numbers(Ex: X=-10 Y= -7). Z should be 0. The "Home Offset" defines a relative zero location and is what a running print uses as zero.

Do a search for YouTube videos on How to Calibrate the E-Steps. I would think that is all you need. Keep in mind that not all YouTuber's are equal. You may want to view a couple of different ones. CHEP is pretty good if you can find one by him.

I have written an Excel interface I use to talk to the printer. There is a section on print recovery that can generate a script (that can be run from within Excel) to re-start a print from any point in a file (using the Byte Offset). So long as your print isn't in the way of the auto-home position it will work. I'll put it and the instructions up if you would like. If you know some VBA you alter the code to suit your needs. There is a link in the file to download a trial version (freeware) of SComm32.ocx that Excel will need to communicate through the USB/Serial port to the printer. I use hairspray as an adhesion assist. Sometimes I have to use an air hammer to get the print off the glass. Other times it pops right off once the glass cools. It isn't consistent enough to count on to hold a print while cycling from hot to cold to hot again.

Being line-to-line with the build surface size may be an issue (where 349.99 x 349.99 may not be an issue) . If you have set up for a brim/skirt/raft then that detracts from the surface size as they take up room outside the model. Non-manifold means Cura is having issues with the model file itself. If you post the model file here someone will take a look and suggest fixes for it. A non-manifold model cannot be sliced by Cura because there are gaps in the model (it isn't water tight).

Did you try printing from the memory card?

Ender 3 Pro. Stock hot end, Orion BB hot end fan. 1.1.5 silent main board. Aluminum extruder assembly. In March the nozzle threads stripped out of the heat block. Repaired with a heli-coil. Filament is from Matter Hackers. I've had it since December. After the initial growing pains the machine has been printing perfect. Now it has a new trick. After printing for 35 - 60 minutes it stops extruding (with PLA at 210. Using PETG at 245 it happens faster). Doing a filament pull results in what you see in the image. What you can't see is that from the extruder to the hot end, the filament looks like an accordion. It is difficult to remove from the Bowden tube until it comes free with a slight pop. There is a lot of friction from the accordion shape. After pausing to clear the blockage and resuming the print, it happens again within 5 minutes. Practically speaking - the machine no longer prints. This started 5 days ago. Since the issue started I have: Put heat sink grease on the inside tube of the hot end. Added a thin aluminum plate to the backside of the heat sink. The fan is clean and sounds like it is reaching operating rpm. The hot end is assembled correctly. There is no leakage. The nozzles are clean. The PTFE Bowden tube is new. The tube fittings are new. The extruder stepper motor runs cool. Retractions do not slide the Bowden tube around. Print speed has been varied from 60 down to 20mm/sec. Retraction has been varied from 6mm down to 2mm. Temperature for the PLA has been varied from 215 to 195. Calibration has been double checked. None of that has made a difference. The extruder starts to skip steps on "prime" moves, and within 1 minute starts skipping constantly. Spring tension appears good as witnessed by the accordion shape. The filament appears to be getting shoved hard into the tube, but there is a blockage formed at the hot end of the bowden tube. I have ordered a stock replacement hot end. I do not have high hopes that it will cure the problem so I am looking for thoughts and ideas. June 30 and the new hot end is in and it's better, but still not right with either PLA or PETG.

There is a setting in Cura under "Quality" called "Initial Layer Height". It sets the height for Layer 1 and I think the default is .28mm. It does not change automatically when you change the regular layer height. If the setting isn't visible, slide the cursor across the Quality bar and click on the gear icon. Then check the box for Initial Layer Height.

There are a bunch of parameters that have an effect on flow. #1 is Extruder steps/mm. There are videos on how to calibrate it and you need to start there. After that, calibrate the XYZ. I use a digital caliper to measure those. Essentially, you measure where the head is from a fixed point, then tell the head to move 50mm and then measure again from the same fixed point to see if it actually moved 50mm. There is a quick formula for calculating the steps/mm based on the measurement. (Move Expected / Measured movement) * current steps/mm). Again, there are YouTube videos. These machines can be superbly accurate and it all starts with being parallel, square, and calibrated. Back to flow, there are settings in Cura under Material that allow you to change the flow for different areas of a print. I suggest you take a look at them and set all of the percentage based ones to 100%. Later you can customize. There should also be a menu on the printer LCD for Tuning. Under Tuning there will be a menu to adjust the flow % on the fly while printing. Flow is dependent on numerous variables. Nozzle size, line width, and of course speed are the main ones. If you are printing at 20mm/sec the flow rate will be 1/2 of what it is at 40mm/sec. A .4mm nozzle at a layer height of .2mm means that 1mm of filament pushed in will produce 30mm of extrusion coming out of the nozzle (IF things are calibrated correctly). At 30mm/sec print speed that is 1mm of filament/sec. There are people who claim to be printing at 150 or 200mm/sec. My Ender 3 would never keep pace with that kind of speed. The hot end just isn't efficient enough to pass plastic through at that speed. I plod along at 50mm/sec for most stuff. Slower gives better results and I get down to 25mm/sec for fancy stuff with a lot of stops and starts. If the extruder motor is clicking and snapping backwards it is skipping steps. That can be a lot of different things from temperature, to heat creep, to a clogged nozzle, to being too close to the build surface, etc, etc. etc. Finding out what is causing the missed steps and under-extrusion is a "Joy of 3d Printing" and you can't get a good print unless plastic is getting pushed at the correct rate. And if all that isn't confusing enough, speed in Cura is expressed in mm/second while speed in a Gcode file is expressed in mm/minute.

There may be something wrong with the model, or at least something that Cura doesn't like. In Cura - what does it look like in Preview? That will be what is sent to the Gcode file. Have you tried to export the file in a different format? (something other than .OBJ that Cura will open)

Have you tried "Spiralize Outer Contour"? It doesn't like horizontal surfaces but anything VaseLike comes out very well. You would need to look at the preview very closely to see if there are areas where the lines are so widely spaced that they don't make contact and you are printing on air.

"Your model is not manifold" error. It can't be sliced because it isn't a solid and it's not closed. You'll need to do something in Fusion to create a solid model. I don't know Fusion but in other programs you could make a solid base and then do Surface Cuts and eliminate the areas that aren't part of the car.

PLA essentially doesn't warp. Long narrow parts may test that statement but I don't see a need to raise the parts off the bed. IF warping happens that's a problem that can be dealt with. I don't want to get you down, but right now all you have is a mess. Keep it simple. Do one part at a time. Put the part on the build surface. Give yourself the best chance at being successful.

Careful is the key word. Heat up the hot end to soften the mess. I try and pick away at it with tweezers. If you have to use a knife make very sure you don't nick a wire.

What happens when you use one of the grips to pull the part?

You need something more accurate that a ruler to perform the measurements. A vernier caliper works well. I think that not enough people pay attention to the frame of the machine. Everything needs to be square and parallel. A carpenters tri-square comes in handy. If (for example) the X beam is at a slight angle then your prints will be off no matter how well the steps are calibrated. Or if the two upright beams aren't parallel then the part will twist as it gets taller. After the machine gets a few hours on it you will want to re-visit the calibration again as things loosen up.

I would start with the slots clear of the raised areas by .25mm constant all the way around. So if a raised area is 1mm x 5mm I would have the slot at 1.5mm x 5.5mm. You can make up a small test piece with some slots on one half and matching raised areas on the other half. Print it and cut it apart and test fit them together so you don't have to print both of the real pieces. If things still don't fit together go to .35 all the way around. Once you have it dialed in then make adjustments to the real parts and print them up.

When printing with wall line count at 3 I've had the infill kinda show through. Increasing the wall count usually gets rid of the marks. At a wall line count of 5 I rarely see it. I've never played with Infill Overlap Percentage but it sounds like the kind of setting that could have an effect on low line count walls and marring of the surface by the starts and stops of the nozzle when putting the infill in place.

Once there is heat damage to the bowden tube it doesn't go away by itself and doesn't care what material is run. BUT...Looking at the video again, it looks like a normal retraction. The motor is turning so slow it's hard to get a feel for what's going on. After the motor starts back up does it start from that retracted position? It's supposed to go back to the previous position. You might check the "Travel / Retraction Prime Speed" setting in Cura. I think the default is 45mm/sec.

Another thing would be how much clearance you left (in the model file) between the raised portions of the yellow piece and the slots in the black piece.