Do the following if you have issues with prints cracking

1. Check for Drafts

Check the area you are printing in for drafts or moving air. Shield your printer from anything that may cause your print to cool too quickly

2. Lower the Layer Height

Cracks can form from too large of a layer height. A rule of thumb is to keep layer height within 20% of the nozzle diameter. Layer height also needs to align with your stepper motors' magic number. A helpful video explaining magic numbers can be found here.

3. Lower the Printing Speed

In your slicer, find the settings for printing speed. Test out several slower speeds in increments of 10 mm/s and see if cracking persists.

4. Decrease or Disable Print Cooling

Some filaments need to cool slowly and the print cooling fan interferes with this process. Start by slowing the print cooling in increments of 10% or fully disable the setting

5. Decrease Infill

Higher percentages of infill can cause internal stress to a part as it cools which may lead to cracking. Lowering the infill by increments of 5% may take some stress off the part.

6. Print in an Enclosure

An enclosure is the best option for controlling the temperature of a part as it cools. There are many options on the market that can be bought or built yourself.