3D printing

[MartyS (Gromit)]

I had not heard of PLA+ before so had to look up what it is.  Seems it's PLA with addatives, usually TPU mixed in to make the PLA softer.

Is the filament a lot softer than regular PLA?  A bowden setup like the Creality uses does get worse as the filament gets softer, using the long tube between the extrusion gears and the hot end makes it hard to control if the filament has give.  Think of it as trying to push spaghetti down a straw, when raw it's easy, as you cook it and it gets softer it will be more difficult.  It can be done but requires a lot of trial and error with the settings.

I'm guessing the PLA+ is only slightly softer, how does it feel compared to the regular PLA?   Does Creality have profiles for different filaments?  PETG is slightly softer than PLA so you may get some clues looking at the differences between the PLA and PETG settings.  Maybe see if the company that makes the filament has a website with suggested settings?

If you are on your own figuring out new settings the first thing to do is measure the diameter of the filament in a half dozen places and get an average.  It could be that your batch of PLA+ is slightly larger and you are over extruding, if that is the case you just put in the new diameter in the slicer and it should take care of it.   The next thing to experiment with is the retraction settings, the distance and speed of the retraction is more tricky to dial in with bowden vs. direct drive, so I can't help with that since all my experience is with direct drive.  Typically you increase the retraction distance to reduce stringing, but too much retraction also reduces print quality and can leave tiny holes so it's a balance between stringing and print quality. 

FYI:  Very rubbery filaments like TPU you can't use retraction at all, and you just have to live with the stringing.  So sometimes you just have to do a lot of post processing to clean up your prints.

[Darth Geek]

Thanks Marty.
I am back to using PLA. And using features like Combing on the Cura slicer I am still having stringing problems when I make multiple one parts at one time. So for now I am sticking to one part at a time.
My printer uses a Bowden tube. But the Retraction setting on the Cura slicer is by default at 5mm, which seems pretty high to me and I don't know if I want to increase it. I am considering getting a Direct Drive but I know the extra weight of it moving around so fast can be hard on the motors and belts.

[MartyS (Gromit)]

Thanks Marty.
I am back to using PLA. And using features like Combing on the Cura slicer I am still having stringing problems when I make multiple one parts at one time. So for now I am sticking to one part at a time.
My printer uses a Bowden tube. But the Retraction setting on the Cura slicer is by default at 5mm, which seems pretty high to me and I don't know if I want to increase it. I am considering getting a Direct Drive but I know the extra weight of it moving around so fast can be hard on the motors and belts.

Bowden setups usually have fairly high retraction values, I've seen numbers as high as 15 thrown around in other forums but don't pay much attention to them since I've never used a bowden extruder.

So that printer has the option to do direct drive?  That's cool usually you are stuck with one or the other.  It's not so much being hard on the motors and belts, it's driving the extra weight can cause artifacts in the print if the drive belt system wasn't designed for that much moving mass.  So you might get ringing or other surface artifacts, and to get rid of them people may use too much tension on the belts and that can damage the pulleys and motor bearings.

Printing multiple parts can be a pain sometimes, and you never get as good a surface as printing one at a time, I only do it for mechanical parts where I don't care about the surface finish (and can cram them close together so the print time isn't a lot longer for the group vs. single parts).  For figures and model parts I always do one at a time to get the best looking surface.

3D printing does require loads of patience, there's lots of test printing, and things take forever to print if you want them to look good.  People get multiple printers just to be able to print more stuff per day.  Technically I have 3 printers, but one I'll probably never used again since it can only print PLA and is small, my big home built printer I may use if I need something bigger than my Prusa can print, but I haven't used it since getting the Prusa.  I have thought about doing a redesign on my big printer, using the Prusa I could print better parts for it, but since I haven't had a reason to use the thing I haven't felt like trying to design a new extruder and gantry.

[Darth Geek]

I've been doing a lot of good prints and learning a lot about the settings. I've had a lot of success, although I still need to do more to get proper dimensional accuracy for parts that have to fit together. I have also started to notice that, even though PLA is not supposed to be effected by moisture, the material that has been out longer has more bed adhesion issues. So I have ordered the bags and desiccant that you suggested and I think it will help.

[MartyS (Gromit)]

 Noticed some 3D models for clarinet reeds on Thingiverse, been trying them out.

 Very tricky getting the thinnest part to print nicely, had to play with the first layer thickness and other settings.  Normally you use a thick first layer and squish it a bit to get it to stick well, but in this case it's vital to have the first layer thin so the leading edge of the reed is correct.  Since it's a wide thin print it doesn't need to stick strongly.

 PETG is a bit soft, great for low notes but doesn't sound great for high ones, now that I have the settings figured out I'll have to try some in PLA and see if that makes the higher notes sound more like a natural cane reed.

[Darth Geek]

Marty have you ever had an issue with Marlin, the software on the 3D printer, having problems? Ever since I've had it the Print From TF menu for selecting the gcode has been really slow. But now it seems to completely freeze up when I go into that menu.

Edit: Odd, now when I try it again it worked okay (that menu is still slow though)

[MartyS (Gromit)]

I've never had a problem like that.

Standard tips would be to unplug it for a few minutes to see if that clears it, or look to see if there is a firmware update for your printer.
Firmware can get corrupted, so even if there isn't a new update flashing the same version it already has can fix issues sometime.  On my earliest printer it stopped recognizing an SD card once and re-flashing the firmware fixed it.

[Darth Geek]

I've never had a problem like that.

Standard tips would be to unplug it for a few minutes to see if that clears it, or look to see if there is a firmware update for your printer.
Firmware can get corrupted, so even if there isn't a new update flashing the same version it already has can fix issues sometime.  On my earliest printer it stopped recognizing an SD card once and re-flashing the firmware fixed it.

Thanks. The version of Marlin on mine is 1.1.6.3 (I think). There is a Marlin 2.0 but from what I am seeing it is mainly for 32 bit boards. I've been thinking of upgrading my board anyway to get the silent one and I think those are 32 bit.

The biggest printing issue I am still having is very noticeable seams on round parts and the occasional blob. I don't think I have overextrusion because the rest of my print looks great, it doesn't look like the pictures of overextrusion I see when I look online.
I was thinking of going to a direct drive. This is the one I found:
https://www.banggood.com/Upgraded-24v-Short-range-Reed-Upgraded-Drive-All-Metal-Hotend-Extruder-Kit-for-Creality3D-Ender-5-or-Ender-5S-3D-Printer-Part-p-1649997.html?cur_warehouse=CN&rmmds=search
It seems like a direct drive should take care of these issues (or at least minimize them).

[MartyS (Gromit)]

I just noticed the ender 5 has a somewhat crappy part cooling fan.  Maybe upgrade that first and see if that solves your problems.

Check out this video:

https://www.youtube.com/watch?v=qW2EEqCh0NI

[Darth Geek]

I printed the Jet Engine model by Catiav5ftw on Thingverse.
It has a few print issues, but they are mostly not noticeable in this picture unless you look close.

[Darth Geek]

Suddenly the X axis stepper motor isn't working. I'll have to try switching the wires to find out if it's the signal from the board or the motor itself. Seems kind of early for the motor to completely die on me though.
I have noticed some roughness of the surface on some of my most recent prints, so I don't know if it's because the motor was having a problem or if it's an over/underextrusion issue. I did buy a direct drive extruder kit, so I'll try that out. Have to fix this motor issue first though.

[MartyS (Gromit)]

Very first thing to check is if the grub screw holding the pulley has loosened up, is the motor turning but simply not moving the belt?

Feel the motor to see if it's overheating.  How does the control board adjust motor current on your system? 

If you plug in a different motor and it runs, feel that motor to see if it's getting hot.

You can over heat steppers and they will stop working when hot, they will start to skip steps a lot as they get too hot.  If you get them way too hot, say over 80°C, the magnets inside will suffer permanent damage. 

Can you still feel the steps when turning the motor by hand (power off and take the belt off to feel it easier)?  If you don't feel the magnet poles locking and unlocking any more the magnets have been over heated.

Possible causes are:

Stepper motor had a flaw and died prematurely.
Board putting out too much current and killing the stepper (feel motor to test).
Stepper controller on the board has died (plug in another motor to test).

Too high a belt tension can cause a stepper to overheat, or wear out the bearings, if it's hard to turn by hand with the belt and power off then the bearings have worn out.

[MartyS (Gromit)]

Oh, and if it is the grub screw when you tighten it back up make sure it's on the flat part of the motor shaft, if the pulley has 2 grub screws tighten the one on the flat first.

[Darth Geek]

Thank you for the suggestions, Marty. I will try that out tonight after work.

[Darth Geek]

Ha, it's been days since I did anything with it because I wanted to wait for the weekend when I could devote hours during the day to deal with it...and it turned out to be a really obvious loose wire connection to the motor.
I had seen some people had 3D printed cable guiding "chain" systems, so I think I will do that to prevent the connections coming loose again.