Troubleshooting print issues + scaling question

[Deshed]

Hi all,

Just got an ender 3 V2 and managed run a levelling print, print a benchy & an adaptor for my dust extractor all fine but now prints keep lifting off the bed in places, to the extent that the first layer is getting pushed off the bed by the extruder on small items.

Not really sure where to start trouble shooting, I'm guessing clean the bed, use brims or rafts, try a temperature tower? It's in my shed, which is insulated but lacking a heater, and it's a bit cold and windy here currently so that's probably not helping. Using PLA & default cura settings.

Unrelated printing question, the bodies on scale3drc all seem to be listed for a fairly narrow range of wheelbase. Is there any reason they can't just be scaled up or down to fit whatever parts I can shove under them? Presumably that would apply to bodies from other sites as well if so.

Any advice would be gratefully received!

 

[imthatguy]

I pretty much always print with a brim, well, at least I used to on my older printer. You could try laying down a layer of Blue painter's tape on the bed. I found the adhesion to work a bit better that way. Printing in a shed probably isn't ideal.

You can scale any file you want, but a byproduct of that is the wheelbase will change, and you'll have to adjust your links.

 

[skinanbones]

I believe that the Ender 3 doesn't have auto sense bed leveling. So its the same as my CR-10 and what i have found that after several multi hours prints, i need to check the bed level agian with a piece of paper. My guess right now is that you need to turn the adjuster wheels out about a quarter to half turn, just to bring the bed a little close to the nozzle.

If that starts to cause issue with elephant foot on the part or it still lifts. I would use glue or masking tape on the glass to get better adhesion.

 

[Svar]

I have the same printer, for very small parts, a brim or a raft is needed. In the settings I select preheat PLA and wait 4-5 min. then I start printing. The only change I have made to my printer in the last year is the bed springs, I still do the level adjustment with the bed at 60C and the hot end at 160c for 5 min. but with the new springs this is very rare. When the bed is cold I clean it before each print with 90% alcohol and a micro fiber cloth.

 

[Deshed]

Thanks for the advice! Warmer weather and blue painters tape have solved the bed adhesion issues, but I noticed it was getting elephants foot even with the bed set to 35C. Apparently squish in the first few layers is a common issue with a few different Creality printers - it seems to have been reduced to a tolerable level so far by adjusting the tension on the z axis carriage rollers, loosening the screws that hold the brass lead screw nut into the carriage, and printing with a raft.

 

[Svar]

Hi,

In Cura you have a setting to correct the elephant foot. Don't loosen the screws it will affect the quality of your print.

#1 The bed at 35°C is low, put it at 60°C, PLA adheres well at that temperature.

#2 Adjust the thickness of your first layer so it sticks well, a first layer at 0.2 or 0.15 is good.

#3 You can correct the elephant foot problem in the Walls section - Initial layer horizontal expansion. Write a negative value like -0.1 and the first layer will be printed 0.1 millimeter inside the perimeter of the part. Make a comparison with different values and look at the effect on your part once sliced.

 

[Deshed]

Thanks, forgot to mention I did the horizontal expansion thing too. One more question, just sliced a body to print in Cura and it's estimating 2 days 18hrs for the first half...is that normal? Was expecting it to take a long time but .

 

[Svar]

Several parameters can make a difference on the printing time.
The thickness of the layers.
The amount of support
Also as you are printing a body, you have many outer walls that are printed slower than the infill. You can always increase the thickness of the layers and the speed of printing the outer walls, but the quality will suffer.
I did some testing with a 1/10 body found on Thingiverse (1/10 Truck body ZIL 157) and for the main part my shortest printing time was 2 days and 19 hrs. Standard quality, standard support everywhere, but with a 4mm support line distance.
Yes, some printing can be very long, my longest project so far was 21 hrs.