What to Do When 3D Print Is Slowly Falling in Resin

Ever watched and wondered what to do when your 3D print is slowly falling in resin mid-process? You’re not alone. This “sinking” or “falling” effect is a common 3D printing issue, and it usually points to trouble with adhesion or your printer’s settings. With some adjustments and a bit of troubleshooting, you can get your print back in good shape.  Here’s what to do when your 3D print is slowly falling in resin and how to get the smooth, perfect prints you’re aiming for.

1. Build Plate Adhesion Issues

One of the top reasons a 3D print might sink into the resin tank is poor adhesion to the build plate. When the first few layers don’t stick well, the print can lose its grip and sink into the resin, leaving you with a failed project.

Why It Happens:

• Uneven Build Plate: If the build plate isn’t perfectly level, your print won’t adhere evenly.
• Dirt or Oil Contamination: Even a tiny bit of dust, oil, or a fingerprint on the build plate can mess with adhesion.
• Incorrect Exposure Time: The first layers might need more UV exposure to properly bond with the build plate.

How to Fix It:

• Clean the Build Plate: Before every print, give the build plate a quick wipe-down with a microfiber cloth. If it’s especially dirty, use isopropyl alcohol (at least 90%) to remove grease or oil.
• Level the Build Plate: Take your time to level the build plate according to your printer’s instructions. Uneven leveling is a common culprit for poor adhesion.
• Adjust Exposure Settings: If the first layers seem under-cured, try increasing the exposure time by 10–20%. This can make a big difference in how well the print sticks during those critical first layers.

A clean, level build plate with the right exposure settings is the key to a solid start for your 3D print!

2. Incorrect Exposure Settings

Exposure settings are one of the trickiest parts of resin printing, but they’re also critical. If your settings are off, layers might not bond properly, leaving your print sagging, unstable, or even failing halfway through. Let’s break down what causes this and how to fine-tune your settings for stronger, more reliable prints.

Why It Happens:

• Insufficient Exposure Time: When each layer doesn’t get enough UV light to cure fully, it’s like building with wet glue—things shift, wobble, and eventually collapse.
• Other Settings Like Layer Height and Lift Speed: These can also play a role. Too fast of a lift speed or improper layer height can make adhesion worse.

How to Fix It:

1. Increase Initial Layer Exposure Time: The first few layers are the foundation of your print, so bumping up their exposure time by 10–20% can significantly improve adhesion. This ensures they cure properly and stick firmly to the build plate.
2. Test with Tools Like Phrozen XP Finder: Not sure what exposure time works best? Download the Phrozen XP Finder, a free tool designed to help you test and optimize exposure settings for your specific resin and printer. For a full walkthrough, check out this guide from the Phrozen Help Center. It’s beginner-friendly and a lifesaver for dialing in settings.
3. Mind Your Layer Height: As noted by All3DP, larger layer heights make printing faster but reduce detail, while smaller layer heights increase detail but take longer. Find the right balance based on your project.
4. Optimize Lift Speed: After each layer, the build plate lifts out of the resin vat. If this speed is too fast, your model can detach or fail. According to Ameralabs, aim for 40–60 mm/min for normal layers and about 5 mm/min for bottom layers.

By tweaking these settings and testing your setup, you’ll get stronger adhesion, better print quality, and fewer headaches with your resin prints!

3. Print Orientation and Support Structures

The way you position your print on the build plate can make or break its success. A poorly oriented print or inadequate support structures can lead to uneven stress, lifting, or even sinking into the resin.

Why It Happens:

• Poor Orientation: If your print has only a small contact area with the build plate, it might not stick well, making it more likely to fail.
• Insufficient Supports: Without enough support, sections of your print might lift, warp, or deform during the process.

How to Fix It:

1. Reorient the Print: Position your model so that more of its surface is in contact with the build plate. A larger contact area means better adhesion and less chance of sinking.
   
2. Add More Supports: Supports are crucial for keeping your print stable and evenly distributing pressure. Thicker support tips (around 0.4–0.5 mm) tend to work better for high-speed prints compared to thinner ones (0.2–0.3 mm), which can break off more easily.
   
3. Balance Support Placement: While more supports generally mean better stability, don’t overcrowd them. If supports are placed too close together, they can fuse and create solid chunks that are harder to remove.
   

By reorienting your model and carefully adding well-placed supports, you’ll reduce stress on the print and avoid sinking or deformation. It’s a simple tweak that can make a world of difference!

4. Resin Tank and Vat Position

Your resin tank’s position is one of those details that seems small but makes a big difference. If the tank isn’t sitting perfectly level, even the slightest tilt can throw off how your resin spreads or how the UV light cures your layers. This can lead to uneven prints or, worse, parts sinking right into the resin.

Why It Happens:

• Tilted Resin Vat: A resin vat that isn’t level can cause uneven exposure, meaning parts of your print don’t cure properly or fail to stick to the build plate.

How to Fix It:

1. Level the Resin Vat:
   • Use a bubble level to check if your tank is flat. These small, affordable tools are available at most hardware stores.
   • For more precision, download a 3D-printed tool like the Phenom Leveling Puck. It’s designed for Phenom printers but might work with other large-format resin printers too. Adjust your printer’s feet or the tank until the level shows it’s perfectly flat.
2. Check Calibration:
   • Once your vat is level, run through your printer’s calibration settings. Most resin printers include a “Z-axis calibration” or a “leveling wizard” in their setup menu.
   • Follow the steps carefully to align the build plate with the resin vat. This ensures the build plate is close enough to the resin for proper adhesion but not so close that it squashes your first layers.

Spending a few minutes leveling and calibrating your tank before every print can save you hours of frustration. It’s one of those little habits that pays off big time!

5. Resin Viscosity and Air Traps

Sometimes, the resin itself can be the culprit when prints go wrong. If it’s too thick, filled with air bubbles, or just not at the right temperature, it can throw your print off completely. These issues often lead to uneven layers, poor adhesion, or parts that shift mid-print.

What Causes It?

• Thickened Resin: Over time, resin can thicken if it hasn’t been mixed well or has sat unused for too long. This makes it harder for the printer to work properly.
• Air Bubbles: Air trapped in the resin can form between layers, reducing adhesion and impacting print quality.
• Cold Resin: As Hiro Creations explains, resin that’s too cold can cause viscosity issues. When resin is cold, it becomes thicker and flows more slowly, making it harder for the printer to lift each layer cleanly from the vat.

How to Fix It:

1. Mix Your Resin Well:
   
   • Stir the resin thoroughly before each use to redistribute pigments and ensure a consistent texture. This prevents thick spots and improves layer bonding.
2. Let Air Bubbles Settle:
   
   • After mixing, let the resin sit for 10–15 minutes so any air bubbles can naturally rise to the surface. This simple step helps eliminate those pesky air pockets that mess with adhesion.
3. Use Room-Temperature Resin:
   
   • Make sure your resin is at room temperature (around 68–75°F or 20–24°C) before starting your print. If the resin is too cold, you can warm it slightly by placing the bottle in a bowl of warm (not hot!) water for a few minutes.

Taking a little extra care with your resin prep can go a long way toward preventing failed prints. A well-mixed, bubble-free, room-temperature resin is the foundation of smoother, more reliable results.

6. UV Light Calibration

Your printer’s UV light source plays a critical role in curing the resin layer by layer. If it’s not calibrated properly, uneven curing can result, causing parts of your print to sink or fail to form correctly.

What Causes It?

• UV Light Misalignment: If the UV light is not aligned or calibrated correctly, it won’t cure the resin evenly across the build plate, leading to adhesion issues or incomplete layers.

How to Fix It:

1. Check the UV Light:
   
   • Use a UV test card or sticker to verify that the light source is functioning correctly. These inexpensive tools change color when exposed to UV light, helping you quickly spot inconsistencies.
   • Visually inspect the UV light for a steady, solid blue glow. Flickering or dim spots may indicate a problem.
2. Run a Test Print:
   
   • Conduct a small test print using minimal resin to check how well the layers are curing. This helps identify if the light’s intensity is adequate across the entire build plate.
3. Use a UV Light Meter (Optional):
   
   • For precision, invest in a UV light meter to measure the light’s intensity. Uneven readings can confirm the need for recalibration.
4. Recalibrate if Necessary:
   
   • Refer to your printer’s manual for instructions on recalibrating the UV light. Many printers include a “light test” function or guidance for adjusting alignment.
   • If you’re unsure, contact the manufacturer’s support team for step-by-step help.

Taking the time to ensure your UV light is properly calibrated can prevent common printing issues like sinking layers and uneven curing. This small maintenance step can save hours of troubleshooting down the line.

Conclusion

Resin 3D prints can stand the test of time with the right materials and proper care, but noticing your print sinking into the resin during the process is a sign something’s off. Fortunately, there are straightforward solutions to tackle the most common culprits.

Start with the basics. Make sure there’s a solid build plate adhesion, fine-tune your exposure settings, and double-check your print’s orientation. These small adjustments can make a big difference in preventing mid-process failures. Regular maintenance, like keeping your resin at the right viscosity and ensuring your UV light is properly calibrated, also goes a long way in creating strong, reliable prints.

Now you’re equipped to troubleshoot and fix sinking prints like a pro. With these strategies, you now know what to do when 3D print is slowly falling in resin. You now are in the direction of your prints turning out beautifully and stand the test of time.