Today, we’re diving into something we see a lot here at GigaParts: those head-scratching moments when your 3D printer just won’t cooperate. You know what we’re talking about—those disappointing times when you excitedly start a print, only to return hours later to find a spaghetti monster or a half-collapsed creation.
Here are a few tips on how to avoid these structural headaches!
The Foundation: Understanding Why Prints Fail
Before we jump into fixes, let’s quickly talk about why 3D prints have structural issues in the first place. Most problems come down to three things:
- Physics is stubborn - We’re literally building objects layer by layer while fighting gravity
- Material quirks - Different filaments have their own personalities and demands
- Design challenges - Some shapes are just trickier to print than others
The good news? With a few tweaks to your design process, you can avoid most of these problems before they start!
Overhangs: The Gravity Challenge
One of the most common issues we see is failed overhangs. When your printer tries to put plastic where there’s nothing supporting it from below, you’re asking for trouble.
The fix: Design with the 45-degree rule in mind. Most printers can handle angles up to 45 degrees without support. For anything steeper, either:
- Add supports in your slicer
- Design your own supports into the model
- Break your model into parts that can be printed flat and assembled later
- Slow your overhang speeds in the slicer settings
Pro tip: Sometimes rotating your model to a different orientation can eliminate the need for supports entirely!
Those Pesky Thin Walls
Ever had a print where parts of the walls just didn’t show up? Or they’re so fragile they break when you look at them funny?
The fix: Check your wall thickness before printing! As a rule of thumb:
- Vertical walls should be at least 0.8mm thick (2x your nozzle diameter for standard 0.4mm nozzles)
- Horizontal surfaces should be at least 1.2mm thick
- For functional parts that need strength, go even thicker - 1.6mm or more
Remember, your slicer needs to fit at least two perimeters within your wall for decent strength.
The Warping Woes
Nothing’s more frustrating than coming back to find your print has lifted off the bed and warped like a potato chip. Warping generally happens because the top of the print cools and pulls the print off the build plate.
The fix: This one’s all about design choices:
- Add rounded corners to your base whenever possible (sharp corners tend to warp more)
- Design with a wider base that gradually narrows as it rises
- For large flat objects, consider adding some recessed areas in the bottom to reduce material
- Make sure to clean the build plate with Dawn detergent and warm water. This will help with adhesion.
- Adjust your infill pattern and/or density. Certain infills and high infill densities can facilitate the warping. Consider honeycomb or adaptive cubic as a pattern. Usually, 10% to 25% infill is plenty. You can also add walls to compensate for less infill.
- If all else fails, add a brim or raft in your slicer settings
Bridging Gaps Successfully
Trying to print horizontal bridges between two points? This is actually doable without supports if you design smart!
The fix: When designing bridges:
- Keep bridges under 5mm for beginners (you can push to 10-20mm as you gain experience)
- Make sure the starting and ending points are solid and well-supported
- Orient your model so the bridge runs parallel to your cooling fan’s airflow
- Design with a slight arc rather than a flat bridge when possible
Building Strong Connections
Those joints and connections are often where prints fail after they’re done. Let’s make them stronger!
The fix: Instead of sharp 90-degree joints:
- Add fillets (rounded internal corners) to distribute stress
- Use gradual transitions between different thicknesses
- For pieces that connect, design with mortise and tenon joints or add alignment pins
Bonus Tips from Your GigaParts Pals
- Hollow isn’t always better: Using infill (20-30%) is often stronger than hollow parts with thick walls
- Layer orientation matters: Remember that prints are weakest between layers, so design with that in mind
- Test critical features: Not sure if something will print? Create a quick test piece with just that feature
- When in doubt, beef it up: It’s better to use a bit more filament than to have a failed print
Stop by for Help!
Still having trouble with your designs? Pop into GigaParts and talk with one of our 3D printing experts for a little help!
Remember, the perfect print often comes after a few not-so-perfect attempts, so don’t get discouraged. Keep designing, keep learning, and most importantly, keep having fun with your 3D printer!