Problems with prusa i3

[JorKsX]

Hello. Hopefully this is right place to post this.

I’m having problems with my prusa i3 clone.

Basically sometimes I get very good prints and sometimes its so bad.

I cannot print small parts like holes for screws, printer like fills the holes and if I try to make 1cm hole, then after the print the hole is like 4mm.

I have tried to print between 30-60mm/s speed and also temp between 170-210. I also tried 0.1 - 0.3 layer height. 0% infill. 20%infill 40% infill.

Most succesful print is done with 20% infill. 0.2 layer height. 190c hotend and 60c bed, with 45mm/s print speed, nozzle diameter is 0.4 and filament is 1.75

No effect, And I print with PLA

I’m using Slic3r software

I’m also getting this spiderweb thingy but I get it at 170c nozzle temp also?

Also the feeder motor starts skipping when I try to print object that height is more then 5cm.

Yes I have turned the potentiometer 90 degrees and It got littlebit better but I think even that 90degrees is too much. The motor did not get hot so I left it there.

And also wht my PLA snaps in half IN the extruder? the filament is not under stress or anything, it just snaps in half and then everything is stuck and I have to dissasemble it.

When I get successful print and the print finnishes and it goes to home. After 1-2min, filament snaps half at the spool. And this is always after the print.

I really need the answer to why my printer wont do small prints, and why the PLA snaps all the time. I have 4 spool of diffrent PLA and it always snaps in extruder.

Every screw is tight and I have tried to loosen extruder screw.

[grantpsd]

How old is the filament. I have seen these issues with filament left sitting, not vacuum sealed and no desicant in the vacuum sealed bag. Filament naturally absorbs moisture from the air. Both ABS and PLA does this. Sometimes I have to throw half a spool away. A filament drier is on my list of things to buy.

[JorKsX]

Is there any way to fix the filament? Baking it or something? I tried to bake it at 85c for 3 hours, it was good for one print. Then it was so hard again and snaps half so easily.

I have no idea how old it is, it’s the one that came with the printer. I have ordered 0.8kg PLA for 35€ so hopefully its better.

Also what about flexible filament? is it any good from hobyking?

Can I fix this bad filament with filament dryer?

And If I buy good PLA, do I need to store it in the bag all the time. because I print every day and the printer is running 15h in one day. So do I need to take the spool away for few hours or can I leave it in the printer for few days?

How long until its going bad?

[RobertHarding]

I would recommend slowing your speed down to about half. You will see less issues at a slower speed and then slowly try increasing it from there. For your questions on the PLA I have filament that has been open on my desk for a year that does not show this issue. I think you should check the temperature on your hotend and make sure it actually is reaching the correct temperature. If the temperature is too low it wont flow smoothly and the gears will snap the filament trying to push it into a cold hotend. Upload some photos of your hotend showing the entire hotend and some showing the different electrical connections. thermistor, temp sensor, fans

I purchased a clone a while back and had massive issues with the direct drive extrusion that most come with. The head was called a MK6, if you google MK6 Extruder you can see if its the same one. The filament would heat up from the motor before entering into the nozzle and cause these issues. I switched to a bowden setup using a E3D V6 and it solved everything. You should know more when the new filament arrives, whether its your hotend or your material.

[JorKsX]

It dosent look like MK6, ebay seller says its MK8?

When I slowdown the speed, it only keeps getting worse…

E3D V6 is on the order list already yes.

I can push filament through hotend easily without force so I think its hot enough?

I’ll see what I can do when I recive new filament.

What upgrades you reccomend?

I have already fixed the Z axis wobble by printing supports and I changed the whole threaded rod because it was not straight.

Do I need to print new belt tensioner if my printer already has them?

Or atleast I have screw thingy where I can increase tension of the belt