Curing Resin Prints in Water? How to Do It Properly

There are many ways that people cure their resin 3D prints, but water is one way that actually works a lot better than people expect. I decided to write an article about how to properly cure your resin prints in water.

Fill a container with water, place uncured resin print into the water-filled container, and expose the container to UV lights in the UV cure chamber or direct sunlight for half the time you would usually give to the print when curing without water.

Keep on reading to get the details and a walkthrough on curing your prints successfully in water.

Why Should I Water Cure My Resin 3D Prints?

When you look into the specific science on what makes resins cured in the first place, you’ll learn that oxygen has a huge role in the photopolymerization process and how it actually inhibits it.

Oxygen is delaying the curing process through a chemical process which doesn’t work very well with the properties that uncured resin has when coming into contact with the UV light.

The reason why you should cure your resin 3D prints in water is because that oxygen is significantly decreased to almost nothing when underwater, leading to a stronger curing process.

Water may be transparent, but it does block some forms of UV light. Luckily, not the UV wavelengths that are present in curing resin so it can easily penetrate through and cure your prints without issue.

Another property that works in our favor with water is how it evenly refracts the UV light all around the transparent container, allowing those lights to reach the inner corners and crevices that your average curing methods may not get to.

You can expect a resin 3D print with a more durable and better looking surface.

Curing in water is the primary method that resin 3D manufacturers like Peopoly recommend.

When parts feel tacky to the touch, a contributing factor is usually the oxygen that inhibits the polymerization or curing process.

The only real downsides to water curing is your part getting wet and needing to dry afterwards.

Some people have talked about their water quality not being the best, like one user who said their tap water in Chicago is pretty cloudy with warm water, then turns clear after sitting. Using that cloudy water led to the resin prints being covered in bubbles.

In addition, typical curing time can be cut in half by using the water curing method.

How to Properly Water Cure Resin 3D Prints

In order to properly water cure your resin 3D prints, you’ll need:

• An empty see-through plastic, glass container (zip-lock plastic bag is another option)
• Water
• A nicely rinsed & cleaned uncured resin 3D print, with supports removed
• UV light from a lamp or direct sunlight
• Nitrile gloves & safety glasses for protection

Follow the steps below to properly water cure your resin 3D prints.

• Fill up your clear container with water from your tap
• Place your cleaned up resin 3D print model in the water, ensuring it is fully engulfing the print
• Direct your source of UV light to the resin print, whether a UV lamp or direct sunlight
• Cure your resin print for half the normal curing time you would use
• Remove the model from the container and let it sit to dry for some time

The process is fairly simple and doesn’t require some complicated steps, just simply have your model in water within a plastic container and cure it for a lesser time than usual until it’s done.

As mentioned above, water curing resin 3D prints has some pretty cool benefits and really gives your models an optimal look.

The process is really well-illustrated in the video below, so definitely check that out!

What are the Best Water Washable Resins?

• Elegoo Water Washable Resin
• Phrozen Water Washable Rapid Resin
• eSun Water Washable Resin

Elegoo Water Washable Resin

The first of the best water washable resins that you can get for yourself is the Elegoo Water Washable Resin that you can find on Amazon.

The first thing you’ll notice when you hit the Amazon page is just how highly rated it is, coming in with a 4.6/5.0 rating at time of writing, with 89% being 4 stars or above.

Now the product itself has many features and benefits:

• Low odor so you don’t stink up the whole work area
• Low volume shrinkage for dimensional accuracy in your models
• High precision with a smooth and clear finish
• No expensive cleaners, alcohols, or hazardous chemicals needed
• Reduced printing times with the rapid aspect of the resin
• Great hardness of print models
• Resultant prints provide clean, bright, fresh, and stunning colors

This water washable photopolymer is compatible with most resin 3D printers, especially those that use a wavelength light source of 405nm. It allows you to easily print your 3D models and wash them using tap water without any hassle.

A user that shared his experience with Elegoo Water Washable Resin stated that he used this resin to print a mermaid model, only taking 4 minutes to complete the whole process of curing the print and the result was pretty great.

Most people love how they don’t need to hold huge tubs of alcohol around and you are saving money since you don’t have to buy them! Several people have had great success with this resin.

Get yourself some Elegoo Water Washable Resin from Amazon today.

Phrozen Water Washable Resin

Next up is the Phrozen Water Washable Resin, also from Amazon which currently just comes in black & gray, though more colors may be released in the future.

It’s referred to as a hydrophilic, meaning easy to be cleaned by water, but make sure you aren’t just dumping the waste water, as it shouldn’t be mixed with drains. Ensure you cure the waste water before disposing of it.

The resin itself comes with great features such as:

• Low viscosity and odor
• Take less time for printing and curing
• Practically elastic
• The prints are tough and the resultant prints are non-brittle
• No nasty, costly, or harmful chemicals

If you’re tired of weak resin 3D prints, then this resin should do you justice. The models come out sturdy and durable, so they can withstand at least some impact before breaking.

This resin isn’t the choice if you want to save money, rather a premium resin that is perfect for your printing ideas, especially miniatures.

One user said that once you dial in the settings, things are really worth it. They said the Phrozen Water Washable Resin (Amazon) is their new go-to resin, having a really low smell compared to other resins.

Prints are easier to get off the build plate because the models have a little more flex in them, and the model holds up nicely when removing supports, though it’s still a good idea to use medium thick supports.

eSun Water Washable Resin

This resin is gaining a lot of popularity with the increasing use of water washable resin for 3D printing. Its high precision, non-brittle prints, and property of being eco-friendly are some of the basic reasons behind its popularity.

Other features of this resin are:

• Low viscosity and easy to clean up
• Great impact resistance with a hardness of 76D
• Excellent print details and great precision
• Compatible with almost all LCD 3D printers
• No harsh odors while printing or cleaning
• Comes in a safe packaging which is leak-proof and wrapped in a plastic bubble bag

It also has low shrinkage, fast curing, and a high success rate when printing with it.

Some people have had a few complaints about the printing, but this may have been due to bad batch. Overall it has positive feedback and produces amazing prints which are easy to wash.

Get yourself some eSun Water Washable Resin from Amazon.

How Do You Dispose of Resin Washable Water

There are two different types of water here when talking about curing resin prints with water.

When it comes to the initial cleaning of your resin print from the build platform, this is uncured resin that is being washed off the print. You need to properly dispose of this by curing the container of water, then removing the leftover resin.

Once that is done, you can dispose of the water down the drain because it doesn’t have uncured resin in there.

With the water that you use after the cleaning process, or your curing water, since it doesn’t have uncured resin in there, it is okay to pour into the drain or sink, though you want to ensure there is no uncured resin from the previous cleaning.

I would recommend getting yourself an ultrasonic cleaner to properly clean your resin 3D prints.

You can check out my article I wrote called 6 Best Ultrasonic Cleaner for Your Resin 3D Prints – Easy Cleaning, or if you want a quick choice that works really well, the Magnasonic Ultrasonic Cleaner is a great choice.