First Layer Cal Issue
My attempts at a "First Layer Cal" have been unsuccessful. The print head output at "Z=0" is so fine that I can not lower the print head. I am going to provide some background and then some experience information.
Background:
1. Purchased an assembled MK3
2. Testing date: 30 JA 18
3. Delivery date 2 FE 18
4. Firmware: 3.1.1.RC5-150
5. " First layer cal" print and Prusa Logo print with machine were perfect
6. Other priorities in life kept me from starting up the unit until 21 JN 18 - almost 5 months since unboxing
Initial experience:
1. I chose not to update the firmware before first operations. Since the prints that came with the machine were so good, I did not want to introduce a new variable.
2. My first operation was to remove the small piece of filament shipped with the machine. I preheated and unloaded the filament without issue.
3. I watched the Prusa start up video several times and I read the handbook carefully.
4. I chose to use the "Wizard" to do a complete check of the functions and calibration
5. All initial "Wizard" checks were perfect: fans, temperatures, and calibration
6. When it was time to load the filament for the "first layer cal" print, I used new Prusa black PLA filament, preheated and loaded the filament.
7. In the Prusa start up video, it appeared to show a reasonably significant stream of melted filament being ejected from the loading process. I did not observe this on my unit. I only got a very fine extrusion that immediately curled up.
8. When I started the "first layer cal", I found the layer to be so thin that I could not lower the "Z axis" to flatten it out.
9. I read as much as I could about problems, verified that the extruder was clean, verified the correct fan operation and temperature setting, and I did a basic nozzle cleaning, but I found no change. In the output.
I would appreciate some advice about next steps to resolve this problem. Did the long time between receiving the printer and first operation have any impact? Do I have to keep trying the nozzle cleaning process? Even though the extruder appears to pull the filament in fine during loading, is there some possibility of slippage of the filament against the hobbed pulley?
Thank you.
Ned McClurg
Re: First Layer Cal Issue
What do you mean by this?
> The print head output at "Z=0" is so fine that I can not lower the print head.
That line to me sounds like your PINDA probe is too low and needs to be raised a tiny bit. If your live-z is at 0 and you cannot go any lower (< 0) since the nozzle touches the hotbed and of course there is no space for the filament to flow then this is a confimation that your PINDA is too low. It needs to be a zip tie high when nozzle is barely touching the hotbed.
Having the printer stored for some time should not be the reason for what you are describing.
Re: First Layer Cal Issue
Hi Ned,
I understand your concern about changing firmware...
I would suggest trying one more print,
Give yourself a fair chance, give the build plate a really good clean with dish detergent and plenty of water, (over the sink)
and dry really well with clean dry paper towels... don't touch the build surface with your fingers, afterwards.
put the clean build plate carefully on your printer heatbed
download Jeff Jordan's "Life adjust Z my way"
the version 6.1 files are at the bottom of the first post,
use the version that matches your available filament. it's ready sliced so should negate slicing errors.
run the print
if the filament looks like thin spaghetti and fails to stick well to the build plate then your live Z is too high
(too small a negative number)
if the filament looks like the sand after the tide goes out, with little ripples in the surface, then your live Z is too low
( too big a negative live Z number)
Live Z values are unique to every printer
if your filament makes a nice smooth even layer, and adheres well to the heatbed, then your live Z is about right
if this fails I suggest updating to the latest firmware and trying again...
if it passes, Change to the latest firmware as soon as the initial excitement dissipates... no point chasing issues with out of date firmware...
also load the latest drivers with latest Slic3r profiles.
My mk2 mmu stood unused for about 6 months at the beginning of the year... it was giving problems and I had a new mk3 to play with!
it printed fine when I got a replacement multiplexor! so standing for a while with PLA in the extruder should not be a problem
Good luck,
Joan
I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK
Re: First Layer Cal Issue
Thank you all for your thoughts. I was able to get a good first layer print by making one basic change. I changed the filament to a newly unsealed roll of filament. I was then able to print one of the SD card test prints perfectly. It appears that the 5 months of inactivity had no impact on the printer, but it did on the filament that was on the machine. I learned a lesson about protecting filament.