I was sitting here with my Anycubic Photon Mono X printing a model, and I realized there were white marks or residue over my resin prints, so this got me wondering, how do I fix this?
After some research, I found some pretty simple fixes to solving the issue of white residue on resin prints.
Cleaning your resin print in two separate containers of cleaning solution helps to reduce white residue and marks on your models. Use an ultrasonic cleaner or a toothbrush to give your model a thorough clean before curing the model. Ensure your resin print is fully dry before curing it.
Keep on reading for a little more detail that should make things a lot simpler and to improve your resin printing experience.
Why Do My Resin 3D Prints Have White Residue on Them?
Resin 3D prints get white residue on them from being cleaned in a liquid solution that has thin particulates of slightly hardened resin. Another reason could be from curing a resin print that isn’t completely dry and still has isopropyl alcohol on the surface. You should dry your resin prints before curing them.
If you are using isopropyl alcohol (IPA), it usually has a tendency to collect all that uncured resin and settle at the bottom of your container. When it comes to washing, swirling, and dipping your prints in that IPA, the residue can easily collect onto your prints.
These dissolved resin residue can form a thin solid layer or white spots on the print.
This is really obvious when you have clear or transparent resin then clean it in that used IPA container. Rather than the uncured resin be cured, they get dissolved in the alcohol, which isn’t great for future print washing.
I’ve personally experienced this where I used some gray Anycubic Eco Resin, then switched to clear resin and saw the residue on some of my washed prints.
In terms of curing resin 3D prints when they are wet, there seems to be a pattern between people curing wet prints and residue showing up on their prints, so it’s likely that this is a key reason why you are getting these white marks.
One user said he washed his resin 3D prints using tap water, and often faced the issue of white marks on his 3D prints. Tap water can actually have impurities or particles that can stick to the prints and cause these spots.
He ended up changing his method of curing and started to wash prints in two different containers of IPA and stopped washing his prints with tap water. This solved the issue and the instances of getting white residue on future prints dropped.
How to Fix White Residue/Marks on Resin 3D Prints
The simple process of preventing and removing white residue from your resin prints is easy to follow once you have the knowledge on how to do it. It’s mainly about your process after your resin print has finished printing.
Once you refine your post-processing methods, you can fix and solve the issue of white residue or marks on your 3D prints.
Follow the step-by-step procedure mentioned below and you will get pretty good results without any white spots on your prints.
Before you begin, make sure to wear your nitrile gloves as usual when handling your resin models.
Lay out some paper towels and remove your resin 3D print from the build plate into the paper towels
Gently dab and press down on the resin print, and very gently wipe it to remove most of the uncured resin
Now that most of the uncured resin is off the exterior, you can place it into your first container of cleaning solution or your ultrasonic cleaner.
It’s a good idea to gently scrub the print with a toothbrush to wipe off more excess resin that has slightly hardened.
You can choose to have a separate container of hot water a little less than boiling point (around 90°C) and soak the print for around 20 seconds to make your supports easier to remove
Remove all your supports
Put the model back into the first container of cleaning solution
Get your mostly cleaned model, and place it into a second container of cleaning solution to clean off the model even more to avoid the residue
Some people then let the print air dry (or use a fan) at this point then put it into their UV light curing chamber
Hopefully that process makes sense to you and you can try it out to get better overall results and less of that white residue on your finished prints.
The video below goes over that step of having a separate container of hot water to help remove those supports easier.
Most people who have experience with resin 3D printing make sure to use two separate containers of cleaning solution so you aren’t dunking the print in the same dirty liquid that you used to original wash the uncured resin off.
Dunking the print in a fresher liquid should make sure that no previous residue gets stuck to the print and will allow you to clean your resin 3D print efficiently.
How to Fix Resin Prints That Get Sticky/Tacky
Resin 3D prints that get sticky or tacky are usually due to not being cured enough. You want to dunk your print in IPA or your preferred cleaning solution, then cure the print under a UV light as usual. You can cure it for longer if you notice that the print is still sticky or tacky.
Washing properly, curing for enough time and then sanding the print is one of the best solutions to deal with sticky prints. This process will get you prints with extra smooth finishes and it’s inexpensive to implement as well.
There are many other cleaning agents available in the market but IPA is one of the ideal recommendation because of its effective and rapid cleaning and quick-drying properties.
Some people have had a lot of luck with ResinAway & 1-Gallon Yellow Magic 7 Cleaner from Amazon. It gives prints a great thorough cleaning and doesn’t have the same harsh smells that IPA has.
I’d definitely recommend switching from IPA to these less harsh, but still very effective cleaning solutions.
Some parts of the prints are too difficult to wash such as pockets, textured areas, tubes, holes, areas with dense supports, etc. In such areas, your cleaning solution may not reach properly and may lead to the sticking of the uncured resin to the prints.
If this is the problem, keep the print in the liquid for a longer time and agitate the print effectively. Scrub the print with a smooth toothbrush or rinse with a paper towel to wipe out the extra reason from the prints.
One user actually did a test to see what variable mattered the most, and they found that when they didn’t give any time for the print to dry before curing, but made use of an ultrasonic cleaner, there was no white residue.
You don’t want to use IPA in an ultrasonic cleaner, but you can actually use the 1-Gallon Yellow Magic 7 Cleaner from Amazon just fine without safety hazards. This is a combination that many experienced resin 3D printer hobbyists use with good results.
It’s likely to be how there is space for the uncured resin to settle, which is why you are more likely to get white marks if you are using a larger layer height as well.
You want to avoid that thin layer of residue on your prints and any leftover water or liquid on the print.
For containers of cleaning solution that have gotten really dirty, you can actually cure the whole container with a UV light, then filter the hardened UV resin out and re-use it.
Michael Dwamena is the founder of 3D Printerly, a platform dedicated to simplifying 3D printing for hobbyists and professionals alike. Owns over 20 3D printers (filament and resin) and has plenty experience 3D printing. Michael has authored over 900 articles, helping millions navigate the exciting world of 3D printing.
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