Closed TOP surfaces

[esteban-pacheco 33]

Just a detail, but you should increase your travel speed.

The higher the difference between printing speed and travel speed, the better. Much less oozing and stringing that way.

I'd recommend 150 mm/s travel speed. Faster is possible, but I like to keep speeds to a minimum on my UMO.

/edit:

If your UMO has problems with 150mm/s travel speed, then you should inspect your gantry. Everything perfectly rectangular? shafts oiled?

 

Everything is well oiled with sunflower  oil! (joke! im using sewing machine oil)

and YES, all is perfectly rectangular, and perfectly Circular...

i've testet yesterday, and im getting better result if i print between 225 and 230 C... thats weird, if youre printing at 50 mm/s and with 0.1 mm layer height, right? if i use 210 C and 215 the Shells are perfect, is just the stupid top layers that doesnt want to Play with those temperatures.

Edited July 6, 2015 by Guest

[danilius 118]

Before you drive yourself completely crazy you want to test various PLA filaments first. The variance in quality between brands/unbranded and colours within even the same brands is quite unreal.

[jonnybischof 60]

Before you drive yourself completely crazy you want to test various PLA filaments first. The variance in quality between brands/unbranded and colours within even the same brands is quite unreal.

 

True enough, though Colorfabb has a very good name...

Sometimes various colors from the same manufacturer also make a big difference. Maybe just try another color if you have any?

[esteban-pacheco 33]

 

Before you drive yourself completely crazy you want to test various PLA filaments first. The variance in quality between brands/unbranded and colours within even the same brands is quite unreal.

 

True enough, though Colorfabb has a very good name...

Sometimes various colors from the same manufacturer also make a big difference. Maybe just try another color if you have any?

 

I have many Colors, ill gona try some today... all Of them Colorfabb.

[francfalco 37]

Isn't this thread is a separate continuation of 'Fatal Under extrusion, Top layers looks REAlly BAD' thread? What happened to that thread - it appears that this issue is being heavily discussed but getting nowhere!

I'm still intrigued to see if  esteban-pacheco has made the .stl available and others have printed it successfully with a nice clean closed top surface - cant see any reference to that?

Can the .stl file be made available please for others to test?

cheers

Edited July 6, 2015 by Guest

[esteban-pacheco 33]

Isn't this thread is a separate continuation of 'Fatal Under extrusion, Top layers looks REAlly BAD' thread? What happened to that thread - it appears that this issue is being heavily discussed but getting nowhere!

I'm still intrigued to see if  esteban-pacheco has made the .stl available and others have printed it successfully with a nice clean closed top surface - cant see any reference to that?

Can the .stl file be made available please?

cheers

 

I already prepared it THE STL, and the INI File... Now, HOW can i upload it here? for you guys to test it?

Edited July 6, 2015 by Guest

[francfalco 37]

I already prepared it THE STL, and the INI File... Now, HOW can i upload it here? for you guys to test it?

 

Exactly my point, if you make available your original .stl (not the sliced file) then we can slice and print from your original file. And then if others can print it successfully, then potentially, with those settings (slicer settings, temp, speed, etc.) can be shared and hopefully help with your issue.

I did request you to send me your .stl file via email: info.co.uk in the previous version of this thread but i never got a response?

But to upload your .stl via this thread, there must be a way surely? Anyone?

[jonnybischof 60]

You could use www.youmagine.com for uploading the stl and other files.

Edited July 6, 2015 by Guest

[gr5 2,172]

Or drop box or google drive or your own website or 10,000 other services. But youmagine would be appropriate.

[esteban-pacheco 33]

So, it is Uploaded, Also the INI File, please test it!

My_Flat.STL on Youmagine

thanks.

[danilius 118]

I can't see any reason your file should not print. It looks quite straight forward. Well, at least we can eliminate that. It's going to need a lot of support, though.

[esteban-pacheco 33]

[media=3464][/media]

today

[esteban-pacheco 33]

a little bit better... but still... not closed

[neotko 1,417]

If nothing changed. Have you check the temperature room? In summer um2/umo+ boards can get overheat on the stepper chips... Just wondering. Because when a stepper heats too much it can understrude, misssteps etcetc

[francfalco 37]

a little bit better... but still... not closed

Are you changing settings?

What are the new settings that are improving the finish?

[esteban-pacheco 33]

well, at the beginning i used Tweak at Z (but it was too clomplex because i Need to run it like 10  times)

what ill try today is to print the top infill and the outer Shell at 25 mm/s (first Shells, then infill) the rest at 50 mm/s, with 223 - 225 C

those temperatures are not uncommon with PLA right?

Edited July 8, 2015 by Guest

[neotko 1,417]

For the speed it's also important to know the layer height. That way you can get a mm3 of material per second.

[esteban-pacheco 33]

0.1

[danilius 118]

I don't know your filament, but at 25mm/s you probably want to print at around 200C to 205C with a 0.1mm layer height. The thicker the layer height at a given speed, the more temperature you need because you have to squeeze out more plastic for the same distance travelled.

At 50mm/s you might need something around 220C at 0.1mm layer height.

The caveat is that it depends on your filament. In your case, I would experiment first with simple models to see how the speed/temp/layer thickness ratio works with it.

[francfalco 37]

what ill try today is to print the top infill and the outer Shell at 25 mm/s (first Shells, then infill) the rest at 50 mm/s, with 223 - 225 C

those temperatures are not uncommon with PLA right?

Well, on the UM2 i print my PLA at 210C

but on the MB Rep 2 at 230C

I wouldn't normally need to go any higher than 230C for PLA

[esteban-pacheco 33]

hello, i was doing a few test yesterday. ... what i've noticed is that the VERY FIRST layer.. is always perfect, the second too, and so on, up to the 5th layer (there the fan is blowing 100% to avoid warping). the next BOTTOM LAYERS begin to be not so homogeneous like the previous ones, principally (i think) because the material begins tho shrink a little when applied (and again - i think) is the reason the bottom and the top layers are not closed...

so i don't know maybe 30 mm/2 (thats sound too slow for me), 210 C and 0.1 mm?

maybe i can print cooler but with the fans a little bit slower?

[danilius 118]

It sounds a little strange that the fans would cause such a drastic change. There is something here we are missing, which is so annoying.

If you can print a hollow cube with 15% infill and 1.2mm wall thickness, say 60mm square at 30mm/sec and 210C and that works out fine, then we have a bigger mystery on our hands.

If that does not work out, maybe it will help tracking down the issue.

[esteban-pacheco 33]

well I can... but the top layers will be not so nice the rest, i think the fans have smth to do, based on my observations,

[gr5 2,172]

You should definitely test this with small prints that take less than 10 minutes to print. A small cube 10mm on edge with only 10% infill should be about right.

The main thing I think you noticed is that it is printing slower on the bottom layer (default 30mm/sec maybe). I don't think this is fan related. Unless your heater block is touching the fan shroud - you could test that by looking from behind the print head and trying to slip a small blade or putty knife or piece of paper between the fan shroud and the nozzle block. No much more likely you are seeing things better due to temperature.

Different can have quite a bit of error. I've seen some temp sensors that print cold by 10C. I normally print at 210C or 220c but occasionally go up to 240C. Never hotter than 240C and never that hot with only 0.1mm layers.

[gr5 2,172]

I think your printer is underextruding. I know you said you just rebuilt it but something is still wrong. There are about 30 causes of underextrusion. I guess I could start posting the list. Here's probably the top ten - this is from an old post I made. #1 is temperature and printing speed but you are within my normal suggested values - you just need to go even hotter or slower. I recommend hotter.

2) Isolator - this is most common if you've printed extra hot (>240C) for a few hours or regular temps (220C) for 100 hours. It warps. It's the white part touching the heater block. Test it by removing it and passing filament though it by hand. Consider reducing the pressure on the isolator from the spring and the bowden tube both (see #5).

3) Curved filament at end of spool - if you are past half way on spool, try a fresh spool as a test.

4) curved angle feeding into feeder - put the filament on the floor -makes a MASSIVE difference.

5) Head too tight? Bizarrely MANY people loosen the 4 screws on the head by just a bit maybe 1/2 mm and suddenly they can print just fine! Has to do with pressure on the white teflon isolator.

5b) Bowden pushing too hard - for the same reason you don't want the bowden pushing too hard on the isolator.

5c) Spring pushing too hard. Although you want a gap you want as small as possible a gap between teflon isolator and steel isolator nut such that the spring is compressed as little as possible.

6) clogged nozzle - the number one problem of course - even if it seems clear. There can be build up on the inside of the nozzle that only burning with a flame can turn to ash and remove. Sometimes a grain of sand gets in there but that's more obvious (it just won't print). Atomic method (cold pull) helps but occasionally you need to remove the entire heater block/nozzle assembly and use flame.

7) feeder spring issues - too tight, too loose

8) Other feeder issues, one of the nuts holding machine together often interferes with the feeder motor tilting it enough so that it still works but not very well. Other things that tilt the feeder motor, sleeve misaligned so it doesn't get a good grip. Gunk clogging the mechanism in there.

9) Filament diameter too big - 3mm is too much. 3mm filament is usually 2.85mm nominal or sometimes 2.9mm +/- .05. But some manufacturers (especially in china) make true 3.0mm filament with a tolerance of .1mm which is useless in an Ultimaker. It will print for a few meters and then clog so tight in the bowden you will have to remove the bowden from both ends to get the filament out. Throw that filament in the trash! It will save you weeks of pain

9b) Something wedged in with the filament. I was setting up 5 printers at once and ran filament change on all of them. One was slowly moving the filament through the tube and was almost to the head when I pushed the button and it sped up and ground the filament badly. I didn't think it was a problem and went ahead and printed something but there was a ground up spot followed by a flap of filament that got jammed in the bowden tube.