Issues with detaching brim / general print suggestions

[Jarls 0]

Hello all, I just got my first printer, an Ultimaker 2 Extended, and I'm trying to adjust my settings to get the best print quality possible. One problem I've been running into consistently is not being able to remove the brim cleanly. Bending it back and forth until it breaks off always leaves a ragged edge, which would not be a big problem to clean up, except that when I do so the bottom layer of plastic will peel away from the bottom of the model. In this photo, I broke off the piece that peeled up:

Other images of this print, pre- and post-cleanup, are here.

All of the settings I changed are listed below; anything else was left at the default value. Any advice fixing this problem or on improving my print quality in general will be greatly appreciated.

Printer: Ultimaker 2 Extended

Filament: Ultimaker Bronze PLA 2.85 mm

Slicer: Cura version 15.06.03

Settings in Cura:

- Layer height: 0.08 mm

- Initial layer thickness: 0.16 mm

- Wall thickness: 1.2 mm

- Bottom/top thickness: 1.2 mm [it's giving me a warning for this?]

- Diameter: 2.85 mm

- Flow: 100%

- Retraction on

- Print speed: 30 mm/s

- Movement speed: 150 mm/s

- Infill: 40%

- Cooling: on

- Fan full at layer: 2

- Supports enabled

- Support everywhere

- Use towers

- Zigzag pattern

- Brim on

- Brim line count: 15

Settings on the Ultimaker:

- Print temperature: 215*C

- Bed temperature: 60*C

- Max acceleration: 2000 mm/s^2

[gr5 2,167]

Fan on full at layer 2 is too soon - this combined with .08mm layer height of layer 2 means you don't get good adhesion. When the fan comes on the nozzle cools down quite a bit and the filament isn't melting the layer below enough to get a good bond. Have the fan come on more gradually - try full fan by 1mm so you get at least 10 layers - or do layer 10. That way it will be 10% fan, then 20% fan, and so on and give the PID controller time to get the head back up to normal printing temperature.

As far as removing brim I use a combination of a razor (e.g. a box cutter) and sometimes I can remove it with my fingernail. I do a thicker bottom layer (0.3mm) so possibly that is easier to remove? But usually I have to get some of it with a razor knife tool. Be careful not to cut yourself.

[DidierKlein 729]

If the brim is well fused with the model, best thing is to cut it with a putty knife.

I also agree with the fan setting coming on too soon and the first layer, put it to 0.3mm it will be better.

Also, from the picture it seems that your first layer is not squished enough? the plate can be slighly higher

[ultiarjan 1,223]

Think your part has a big footprint so you don't need to use a brim at al imho ..

If you'r worried about sharp corners lifting you can also make small "ears" on it in CAD, so you have less material to remove, like this;

[Labern 774]

I tend to hold a sharp knife at 90degrees to the part and scrape the edge. this way you don't cut into the model.

[danilius 118]

The simplest solution is not to use a brim. For the model you posted you simply don't need one.

Also, as has been mentioned, fans have to come on slowly. So, allow several layers for the fans to ramp up speed.

[Jarls 0]

Thanks all for the replies, very informative. For my next print I'll adjust the fan settings and make a thicker bottom layer. I'll also try out the mouse ears/no brim.

I do have a few more brief questions about working with Ultimaker:

 

• The glassy finish on the bottom of the part is not ideal for me. Does UM PLA like printing onto painter's tape? I assume this will give a more textured surface.
  
• I'm having some issues with stringing embedded in the part. Should I try to use combing to help with this?
   
  
• Can anyone explain the warning Cura is giving me for bottom/top thickness?
  

 

Didier: I've been running Ultimaker's bed-leveling procedure so I can just barely slip a sheet of paper between the nozzle and the bed. I've actually been thinking the bed might be too close, as some of the deposited filament has been getting smeared back onto the nozzle on the first layer. Is there something else I should be trying here?

[gr5 2,167]

The glassy finish on the bottom of the part is not ideal for me. Does UM PLA like printing onto painter's tape? I assume this will give a more textured surface.

 

Yes, this is an older technology but works great. No heat needed (although 40C helps the filament flow into the cracks a bit but turn off heat after first layer is done). Although if your part isn't sticking well try cleaning the tape with isopropyl alcohol. And if the tape lifts off the glass use wider tape.

 

I'm having some issues with stringing embedded in the part. Should I try to use combing to help with this?

 

Unchecking combing can reduce scars/marks on visible layers (bottom layer, top layer). This increases stringing across empty spaces but reduces scars/marks embeded in solid areas.

 

Can anyone explain the warning Cura is giving me for bottom/top thickness?

 

Your settings look okay - what's the warning? I see your thickness is a multiple of layer height so you should be good. Did you hover mouse over this to get a warning popup message?

 

Didier: I've been running Ultimaker's bed-leveling procedure so I can just barely slip a sheet of paper between the nozzle and the bed. I've actually been thinking the bed might be too close, as some of the deposited filament has been getting smeared back onto the nozzle on the first layer. Is there something else I should be trying here?

 

That could be - actually you might be too *far* from the bed. At any rate stop messing with leveling procedure and at this point adjust by turning the 3 screws while it is on the bottom layer. Try turning the 3 screws identical amounts as the bed is probably "level" just not at the right height. Alternatively push up or down on the bed while it prints to see which way you need to move it.

[Jarls 0]

Your settings look okay - what's the warning?  I see your thickness is a multiple of layer height so you should be good.  Did you hover mouse over this to get a warning popup message?

 

Thanks for the detailed response. Actually there's no error message, but the value is highlighted in yellow. I've noticed that when I put some extreme values in, the highlight switches to red, so I presumed it was sort of a yellow = caution, red = danger situation.

I'll also try the bed adjustments you suggest. I would have never imagined the nozzle actually needs to be closer.

[danilius 118]

Learning how to level the bed was the hardest thing to achieve for me. You have to babysit your prints at first until you are confidant. After that, once your bed is levelled you will rarely have to do it again. Even if you move the machine around, or hold it upside down to retrieve a lost part, and you are hearing the voice of experience

[gr5 2,167]

Actually there's no error message, but the value is highlighted in yellow. I've noticed that when I put some extreme values in, the highlight switches to red, so I presumed it was sort of a yellow = caution, red = danger situation.

 

Try hovering the mouse over the yellow (if you don't have a mouse try installing Cura on a computer with a mouse). I think you will get an explanation of why it turned yellow. I'm curious to know what the text says.

[ultiarjan 1,223]

if you don't have a mouse try installing Cura on a computer with a mouse

or just plugin a mouse ?

[Jarls 0]

Try hovering the mouse over the yellow (if you don't have a mouse try installing Cura on a computer with a mouse).  I think you will get an explanation of why it turned yellow.  I'm curious to know what the text says.

 

Yeah that's what was confusing, it just shows the normal tooltip message ("This controls the thickness of the bottom and top layers..."). I'm wondering if it's just Cura acting screwy, as I've had a few other instances of weird things happening.

Edited September 18, 2015 by Guest