Negative angle printing is not smooth

This is for general discussions. Also FAQ can be found here.

Moderator: speedake95

Post Reply
Boris
Posts: 45
Joined: Thu Jan 15, 2015 11:59 pm
Location: Moscow
Contact:

Negative angle printing is not smooth

Post by Boris »

Hello guys.

There is another question about quality :)

Here, on a picture you may see legs printed without supports with ABS(I dont think supports bring any difference in that case).
As you see, the positive angle, outside of legs printed very well. But negative side is very ...steppy :)
Well, is there any way to smooth things like that ?
I can't rotate the model for many reasons :(
Attachments
negative_angle.jpg
Felix 3.0 x2 extruders

fesch
Posts: 35
Joined: Fri Dec 05, 2014 11:14 pm
Location: Luxembourg
Contact:

Post by fesch »

I have the same problem and would be really happy about a tip on how this could be avoided.

Most of the time I can turn my prints in some other way so that I don't need to print negative angles, but this is not always possible. :-(

fesch
Posts: 35
Joined: Fri Dec 05, 2014 11:14 pm
Location: Luxembourg
Contact:

Post by fesch »

I'll answer my own question, at least partially: Today I've added an additional fan near the extruder. This reduces the distortions on the printed negative angles. Maybe I'll have to move it closer to eliminate them totally ?

frankjoke
Posts: 150
Joined: Sat Dec 28, 2013 6:07 pm

Post by frankjoke »

Strange, on ABS I would not use fan at all!

Anyhow, which slicer do you use? How many perimeters (solid outside lines) and do you print them inside out or outside in?

I use 3 perimeters on Kisslicer from inside to have best coverage of such angles.

On top print speed and material matters as well because it flows down easily without any support.

satoer
Posts: 436
Joined: Mon Oct 01, 2012 8:00 pm
Location: Netherlands

Post by satoer »

With large overhangs you get a better quality if you print the inner Perimeters first.
steep.jpg
This was sliced with Slic3r, it's halve a inner sphere and printed upside down. The layers near the middle are almost horizontal and still printed perfectly. (used a layer height 0,2mm with a speed of 150%)
My Felix 1.5 printed designs on Thingiverse
E3D V6 Hot end upgrade for your Felix
Tweezer bracket for your Felix
Led bar upgrade for your Felix

frankjoke
Posts: 150
Joined: Sat Dec 28, 2013 6:07 pm

Post by frankjoke »

satoer,

this is a very big print where every loop takes pretty long. On such small prints for the legs the material has not a lot of time to bind and cool and it's then too hot on the next perimeter and 'rinning' down.

Post Reply