Notifications
Clear all

First Print Problems  

  RSS
andrew.l7
(@andrew-l7)
Eminent Member
First Print Problems

Hi,

I have carried out the V2 calibration and started my first print - the gear. It seems to start off okay, with the PLA stuck well down, but then, after just a couple of minutes, parts of the model comes unstuck and parts start to be taken off the bed, whilst other parts remain firmly stuck. Does anyone have any ideas (see pic).

Posted : 29/05/2017 5:55 pm
Filip Safran
(@filip-safran)
Eminent Member
Re: First Print Problems

This doesn't look very good. Even the skirt doesn't seem to be stuck to the bed.
I'd check the V2 configuration print again and adjust Z. The line needs to really stick so you can't easily take it off.
There are a couple more calibration tests that guys here recommend, but I managed to adjust my Z axis properly with V2 so I didn't use other.

have you tried printing the Prusa logo? How did that go? Can you try and print that, only the first layer and then stop the print, take a picture and post it here? (again, others may have recommendations for better calibration prints, but these worked for me with no issues)

Posted : 29/05/2017 6:16 pm
andrew.l7
(@andrew-l7)
Eminent Member
Topic starter answered:
Re: First Print Problems

Filip,

Okay, I will do that.

I seem to be having conflicting reports about the z calibration and the height of the probe. My Z reading is about 1,6mm - is this too high?

Thanks,

Posted : 29/05/2017 6:46 pm
Filip Safran
(@filip-safran)
Eminent Member
Re: First Print Problems

The probe should idealy be 0,7 - 1,0 mm above the nozzle. I had to do the calibration and lower the probe 3 times before my nozzle didn't catch the piece of paper. Then live Z adjustment took another 0,75 mm lower before the sticking was OK (you'll see the difference, you won't be able to sweep away the line with your fingers but you'll have to lift one end with your fingernail and then pull the rest in the direction it was printed in, that's a good indication it's sticking well).

I noticed now in your picture that your PEI has something on the surface? Is that scratched or did you smear glue on it?

Posted : 29/05/2017 7:43 pm
andrew.l7
(@andrew-l7)
Eminent Member
Topic starter answered:
Re: First Print Problems

Thanks for the probe height advice.

The general area of smearing is the glue. The line is the remnants of the V2 calibration, not properly removed as I knew that the gear model would not touch it.

Posted : 29/05/2017 8:20 pm
Filip Safran
(@filip-safran)
Eminent Member
Re: First Print Problems

Remove the glue and recalibrate the Z axist position without it.
My guess is the V2 calibration seemed to go well because of the glue, while in fact you didn't adjust Z correctly.
The line needs to stick to the PEI surface without any glue. You don't need any adhesive for PLA in most cases, I've printed a thin - 200 x 180 mm (max dimensions) contour with lots of sharp edges and points, no problem at all. Just clean the PEI, adjust Z well enough and everything will stick and even if it doesn't, for PLA you can just increase the bed temperature by about 5 °C

Posted : 29/05/2017 9:57 pm
andrew.l7
(@andrew-l7)
Eminent Member
Topic starter answered:
Re: First Print Problems

Filip,

Okay, will try that.

Thanks,

Posted : 29/05/2017 10:05 pm
JeffJordan
(@jeffjordan)
Member Moderator
Re: First Print Problems

the photo above is a typical picture of a bad first layer adjustment !

sorry that i've to mention it another time:
getting the first layer adjustment right with only the v2calibration gcode is like winning in a lottery.
so i've set up a thread about a more reliable method to do so.

go for the 4th version of the little calibration surface, but read at least the first sites of the thread to get how it works and how to interpret the results.

if it helped you, keep that thread alive with a short post there... so that other newcomers get a chance to read it.

dem inscheniör is' nix zu schwör...

Posted : 29/05/2017 11:30 pm
Filip Safran
(@filip-safran)
Eminent Member
Re: First Print Problems

I feel that V2 is a good code for quickly getting the print to stick. It'short and quick so if you need to do it again, you can get it done with minimal filament loss and in minimal time.

Then you can use the Prusa logo or the g code Jeff made to check if the infill is good or that the lines are spread correctly.

But I wouldn't dismiss V2, it is for fast adjusting of Z axis and worked well enough in my case.

Posted : 30/05/2017 10:42 am
andrew.l7
(@andrew-l7)
Eminent Member
Topic starter answered:
Re: First Print Problems

Okay, finally moving forward with this I think.

I won't bore you with the re-calibration/PINDA height adjustment details but the photos show the first actual printing attempt. Satisfactory do you think, or still some tweaking to do?

Two issues that I think are pertinent: firstly the initial extrusion of PLA to prime (I think) the extruder is always very flat, like it is way too close to the bed. However, the print seems fine. Secondly, there is a clicking at the extruder feed which is constant, but not as loud as it was at one point when I had to unload and reload the filament. When I unloaded it, the last 4-5 cms were marked with a screw impression from the gear.

The diagonal line from the "S" to the "A" is when they filament was being restricted from being supplied due to the filament holder mechanism not being free enough.

Thanks,

Posted : 05/06/2017 2:47 pm
Share: