3D Printing a rounded base - Problem.

[Catlord 17]

Is it normal that the nozzle bump into the already printed part ?

we can see that almost 0.5mm of the Nozzle is directly printing into the material. (I'm a newborn in 3d printing but I find this weird)

Edited October 23, 2015 by Guest

[Titus 170]

I think your part is not getting enough time to cool down before the next layer. Therefor it stays glass like and you push it around when printing the next layer, and thus push it 'outside' the part.

[gr5 2,192]

It's normal but it's more complicated - the PLA shrinks as it cools - within milliseconds it is already like a liquid rubber band. When you have convex overhangs like this each layer above tries to pull inward the layer below and you get a lip or a raised edge. There's tons of posts about this in other parts of the forum with really interesting slow motion macro photography and 2 possible solutions. The main fix is MORE FAN. Or just do less overhangs. Some day we'll have a printer with 2 heads that prints a soluable second filament for support. Some day.