Brittle PLA prints

Hello everyone.

Since my extruder/hotend jammed, I took it apart and after reassembling it, my prints became very brittle. I did not change anything except stepper voltage (from 0.425 to 0.55). I also recalibrated my steps/mm. And now, my prints are fragile, "hairy", not shiny and brittle. Could it be my thermistor issue (isolation or broke) caused while reassembling? However, my temperature reading seems to be fine ( it reads the temp it should). I have tried using different plastic, same thing. I am printing at 190 degrees, however, I tried to change it up to 220, same thing happens.

Here are few photos:

[fbcdn-sphotos-h-a.akamaihd.net]
[fbcdn-sphotos-h-a.akamaihd.net]
[fbcdn-sphotos-h-a.akamaihd.net]
[fbcdn-sphotos-h-a.akamaihd.net]

It looks like you're under-extruding from the photo. Steps/mm should not change unless you change the gearing on your extruder. Have you tried reverting to the original value?

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

While reassembling the extruder, I retightened every single bolt and screw, so the forces pressing fillament have changed, so as a result, my steps/mm changed. Without recalibrated steps/mm, I got like 5mm off. Under extruding, by that you mean my feed rate is too low? If so, even when I turn my extruder gear by hand, the fillament coming out is grey, instead of black, and it looks not the same, as it looked before.

What extruder / hot end are you using? Increasing the force on the filament should not have changed the steps per mm, unless your extruder was slipping prior to the recalibration.

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[3DKarma.com] - suppliers of quality, affordable 3D printer kits and filament for the UK market.

Quote
3dkarma
What extruder / hot end are you using? Increasing the force on the filament should not have changed the steps per mm, unless your extruder was slipping prior to the recalibration.

I am using RepRap 3drag printer with the hotend/extruder it comes with.

Reuploaded pic


Edited 1 time(s). Last edit at 07/11/2014 07:17AM by Capinho.

Definitely uneven extrusion. Possibly wrong steps/mm

What is your print speed?

Get an IR/laser temp gauge.

Quote
MrBaz
Definitely uneven extrusion. Possibly wrong steps/mm

What is your print speed?

Get an IR/laser temp gauge.

My print speed is 50 mm/s