Height problem platform

[olafson 0]

Hi,

I have a new Ultimaker and assembeld it by my self. Everything is working fine.

But when I am printing a wide object like a box of 8x4cm, the nozzle is scratching on the layer he just printed. It is happening when the printer is at a height of approx 10mm.

Only when I am printing something small like a monopoly house, its working fine and do not scretch.

Before each print I run the "bed leveling wizard" and screw each corner to zero. (so it is in contact with the nozzle)

I also tried to start with a bed level of 0,1mm lower, but then the filament is not sticking onnthe bed anymore when printng the first layer.

Somebody know what the problem is?

[illuminarti 18]

What makes you think the head is catching on the layer below? Can you post photos, and/or video. They gcode would be good, also.

What print speed, temp and layer height are you using?

 

[olafson 0]

I am not sure if the height of the platform is the issue of course, due to no experience yet :-)

But I am hearing the nozzle making a scrathing and gridding sound, also I see that the layer which is printed is feeling very rough and looking sandy.

Temp: 210 degrees

Filament: PLA 2.89mm

Layer hight: 0.1mm

I am not in the occasion to make picture/video of it, will post that tomorrow

[gr5 2,004]

also tried to start with a bed level of 0,1mm lower

 

So don't do that, lol.

How large is the print? 8X4cm? You probably have the corners lifting off the blue tape. This is very common. It happens because the PLA upper layers shrink as they cool and they pull hard on the part and lift the 4 corners.

You can fix this many ways.

1) First wipe your blue tape with isopropyl alcohol (also called rubbing alcohol). You can buy this at any store that sells bandages such as a supermarket or drugstore. This removes the wax from the blue side of the tape and increases stickyness. Also if the blue tape itself lifts off the bed it helps to get larger pieces of tape available at any store that sells paint and paint brushes. Ask for "blue painters tape". This one thing will help you more than any other thing below.

2) Add a brim. Cura has a brim setting on the adheasion section. Do about 10 passes. This will help keep the corners of your part down.

3) Print first layer slower and hotter. I always set my temperature to 0 in cura and adjust it by hand using either cura print dialog or ulticontroller. For large parts I print the first layer at 240C and then lower the temperature after it is done with the first layer. Also squish that PLA into your bed nice and hard with the bed nice and high.

4) Don't infill the first layer. This might not be practical depending on what you are printing but cura allows you to not fill the bottom or top layer - it's a checkbox.

5) Get a heated bed. Not neccessary for PLA but this helps also. Step 1 and 3 alone are usually enough.

 

 

[olafson 0]

But I can not see any lifting of the corners. Everything is sticked to the platform very well, also the tape.

The problem occurs over the whole surface and not only at the corners but also in the middle. Does you advice stay the same?

How can I attach a photo here? I only find an url link

 

[gr5 2,004]

Then I was wrong.

To post a picture, Click on "Gallery" at the top left of this page. Create an album, upload a picture, then "post" a response to this topic and click on "my media" next to the smiley face.

 

[olafson 0]

This is the surface how it looks after the printer nozzle scratch over the surface.

 

 

 

 

 

[gr5 2,004]

I see no picture. Sorry.

 

[olafson 0]

Now the foto is visible. It was still on the private mode :-)

 

[illuminarti 18]

It looks like the problem is just that the solid top isn't covering over the infill very well. It takes a few layers to get a solid cover over the 'sparse' infill. Make sure your fan is turned on, and try printing slower, or thicker layers. It looks similar to what we were just discussing over on the google group.

I recommend making sure your top/bottom thickness is set to 1mm or more, to get a smooth top on 0.1mm layers.

 

[olafson 0]

Hi Illuminarti,

It's fixee now. Have it under control because of your advise!

Thx

Regards,

Olaf

[illuminarti 18]

Yay! I'm glad you got it working. :-)