My first layers are good. When print is finished and l remove from bed the bottom layer is good but middle of object breaks easily apart?
I would start with increasing the extruder temps a bit +5-10º I would look for under extrusion second.
When filament comes out of the nozzle, it should be hot enough, long enough to partially melt the filament below and beside it. That way the new filament and the previously laid filament weld together.
If the part breaks easily then the filament is coming out too cool and/or cooling too quickly.
In addition to @kitedemon’s suggestion to raise the temperature, you could also try two other things:
- slow the fan speed down so it doesn’t cool the filament as quickly.
- slow the print speed down so the hot nozzle lingers a bit longer over the newly deposited filament.
Both these changes will slow the rate at which the new filament cools, giving it more time to bond to previous layers.
I’m sending pictures of the part and on the big piece it is rough to touch and the other pieces which broke off don’t look right either. I’ve printed three of these before with no problem?
On the spool it says bed temp between 40-60 deg and nozzle temp between 180-220deg and my bed is 65 deg and nozzle is 205 deg.
Should l increase?
I might increase the extruder temp some but it looks like under extrusion to me.
@496 From what I can tell in the images it appears to be under extrusion more than temps. (It could still be temps however)
If you think it looks like this there are a number of things to check. If it just ‘happened’ I would suspect a partial nose clog first and do a cold pull. It might be the fast solution.
I m new so a cold pull is? I can clean the nozzle but every time I change filament l always heat nozzle and push down then pull up. And when I put new filament in l always push some out of nozzle
Also I have a direct feed so my bowden tube is very short.
A cold or atomic pull is when you allow the hot end to come up to temp then shut down the heating disable the steppers and around 85-90º you pull the filament from the extruder. The idea is the cooling filament collets any junk in there and it is all pulled out.
1 try a print with increased nose temp. and or slower fan speeds
2 switch filament to something else.
3 does the print look like images of under extrusion? try a cold pull, test print
4 disassemble and check everything visually
4.1 calibrate the extruder and re level test print.
Just a quick thought as well, Verify your nozzle size it setup properly in your slicer, If you have a .4 in the printer but have your slicer setup for a .3 you will see exactly this as well.
Double check that your flow rate is set to 100%,
My nozzle is correct.
I’m using prusaslicer and where is the flow rate on slicer. Is it the print speed override ( max volumetric speed)?
no print speed is different, Flow is the amount of filament pushed at a specific speed, Print speed will increase both speed and Volume
I do remember having this exact issue several years ago, I do remember it was a slicer setting I had changed trying to tweek stuff and never changed it back. Let me have a look around and see if I can jog my memory.
If you don’t mind I just want to eliminate extrusion first.
Could you run the 100mm extrusion test first and let me know if its within 2-3%?
OK. I’m new so how do I do that?
sorry, I will give some additional information.
I have included a link from another site that has an extremely good guide on doing just this
They have it compiled much better than I can explain.
Basically you are going to request to extrude 100mm of filament through your nozzle, and then measure and see if 100mm actually extruded.
Hope this is OK
I’ve done it but I’m not sure where I have to measure. I have a direct drive so do l measure from the nozzle, or l have a short piece of bowden tube do l measure there. When I make my mark and do the test do l measure if l see my mark from there to what point. The test l did l marked 100mm and did test and l still saw my line. I measured from line down to nozzle?
if you have a short piece of Bowden on the DD yes you can use this as a guide, as long as you use the same ref point before and after the extrusion.
It really doesn’t matter where you measure from as long as you can see it before and after.
Usually I will place my mark at 120mm, Extrude 100mm and then measure the difference. Ideally you want to measure 20mm left at the end of the test.
I measured 100mm, 110, 120 mm from same place. I went to extruder on my lcd and extruded 100mm out and watched and waited till it stopped. I measured from same place and l saw my 100mm line and l got 31mm. So if this is correct l calculated my e steps /mm setting, which is 93. 93x100=9300. Divide 9300 by 31 and l got roughly 134. If this is correct so lve been under extruded all along. I don’t understand why, how…