5 Things That Will Ruin Your 3D Print (And How to Avoid Them)

You've got the file, you've dialed in your slicer settings, you hit print... and three hours later you're staring at a pile of spaghetti or a warped mess that belongs in the trash.

Sound familiar?

3D printing can be incredibly rewarding, but it's also unforgiving when things go wrong. Here are the five most common killers of good prints – and how to avoid them.

1. Wet Filament (Yes, Really)

The problem: Filament absorbs moisture from the air. When you print with wet filament, that moisture turns to steam inside the hotend, causing bubbles, stringing, poor layer adhesion, and a rough, inconsistent finish.

How to spot it:

• Popping or hissing sounds during printing
• Excessive stringing between parts
• Brittle or weak prints that snap easily
• Rough, bumpy surface texture

The fix: Dry your filament before printing. PETG and nylon are especially hygroscopic and will soak up moisture fast. Even PLA can benefit from drying if it's been sitting out for weeks.

We covered this in detail in our filament drying guide – it's one of the easiest fixes that most people overlook.

2. Bad Bed Adhesion

The problem: If your print doesn't stick to the bed, it'll warp, shift mid-print, or just turn into a tangled mess of plastic spaghetti.

How to spot it:

• Corners lifting off the bed (warping)
• Print detaching mid-job
• First layer not squishing properly

The fix:

• Level your bed properly (and check it regularly – beds shift over time)
• Clean the print surface with isopropyl alcohol before every print
• Adjust your Z-offset so the first layer squishes just enough
• Use adhesion aids: glue stick for PLA, painter's tape for tricky materials, or a PEI sheet for consistent results
• Increase bed temperature if warping persists

A good first layer is 90% of a successful print. Get this right and you're golden.

3. Wrong Print Temperature

The problem: Too hot and you get stringing, oozing, and sagging overhangs. Too cold and layers won't bond, leading to weak, brittle prints that fall apart.

How to spot it:

• Stringing and blobs = too hot
• Poor layer adhesion and under-extrusion = too cold
• Inconsistent extrusion or clogs = way off in either direction

The fix: Run a temperature tower test. Print a calibration model that tests different temps in 5°C increments and see which gives the best results for your specific filament and printer combo.

Don't just trust the manufacturer's recommended range – every printer is different, and even batches of the same filament can vary.

4. Ignoring Retraction Settings

The problem: Retraction pulls filament back into the nozzle during travel moves to prevent oozing and stringing. Get it wrong and you'll have hairy prints or clogs.

How to spot it:

• Strings of plastic between parts (under-retraction)
• Gaps in layers or grinding filament (over-retraction)

The fix: Tune your retraction distance and speed in your slicer. For direct drive extruders, start around 1-2mm. For Bowden setups, try 4-6mm. Adjust in small increments until stringing disappears without causing under-extrusion.

We covered slicer settings in our Slicing 101 guide if you need a refresher.

5. Unrealistic Expectations for Overhangs and Supports

The problem: Gravity exists. If you're trying to print a 90° overhang without supports, you're going to have a bad time.

How to spot it:

• Sagging or drooping on overhangs
• Failed prints where unsupported areas just collapse
• Messy surfaces where supports were removed

The fix:

• Use supports for overhangs steeper than 45-50°
• Orient your model in the slicer to minimize overhangs
• Use tree supports for easier removal and cleaner surfaces
• Adjust support density and Z-distance to balance strength and ease of removal

Sometimes the best fix is just rotating the model 90° so gravity works with you instead of against you.

Bonus: Skipping the Test Print

Look, we get it. You're excited. You want to print that 12-hour model right now.

But if you haven't printed anything in a while, or you just changed filament, or you tweaked your settings... do a quick benchy or calibration cube first. A 30-minute test print can save you from wasting an entire day on a failed job.

Still Having Issues?

Sometimes the easiest solution is to just let someone else handle it. If you've got a design you want printed but don't want to deal with the troubleshooting, that's literally what we're here for.

Order a custom print and we'll take care of the rest.