Cracking between layers

When I print a large structure on my mini in the high speed mode after it has finished and cooled I notice cracks in the corners where layers are separating. The corners that are on the build plate are also curving upwards. Any idea what is causing this and how to make it stop?

Image attached below.

Which material, ABS?

What type of filament/brand are you using and at what temperature are you printing?

You could bump up the temperature a couple degrees to promote better layer adhesion. Could also try to reduce your layer height.

I’m going to assume it’s ABS…

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  1. Your part is cooling too quickly. Build an enclosure around the build area of your mini to hold the heat in and let it cool more slowly. Be careful not to cover your electronic exhaust fans.

  2. Reduce your layer height…head towards 0.05mm and see when it stops splitting.

  3. Raise your nozzle temp a few degrees

  4. Turn off the part cooling fan during the print unless it has super fine details.

  5. When all else fails, you can make ABS glue and clamp the split together and wait for the abs glue to dry in about a minute. Also can use abs slurry to fill the crack like putty.

All of these should help. Good luck!

Jim

Yep. If its ABS:

  • increase extrusion temp a few degrees
  • use minimal fan… 40-50%

.05 layer height is a bit extreme, but makes sense since it will be deposited and cool almost immediately. But it will take an excuciatingly long time to print. I regularly print at .3 layer height using a .5 nozzle… just bump the extrusion temp by a few degrees.

If you still have problems, an enclosure would be the next real fix for your print environment.

Thank Jim! I will try your suggestions over the next couple of weeks and see how it goes.

I’m not sure if this was the only solution, but after building a enclosure, splits were minimal. However, ever since I went under Expert : Open Expert Settings and changing Fan speed min and Fan speed max to 40 instead of 40/60 I haven’t had an ABS split since. Might give those two a shot first and see how it goes.

Just wanted to add a solution that seems to be helping for me. I’m printing a 5.5"x5.5"x2.1" “box” for an electronics enclosure with ABS and getting splitting on the corners. I tried most of the suggestions except for building the printer enclosure and I was still getting cracks.

So what I did is manually take out the G code to turn off the heat to the printer plate after printing. After the print finished, I slowly manually decreased the temperature of the plate in small increments over about a 1 hour period. Presto, I was able to get the part with no visible cracks.

I did this manually, but I was looking at G code some and it wouldn’t be hard to automate this by adding pauses to the end G code after each small change in the plate temperature.