I was once in a position where I found it frustrating to clean & cure resin 3D prints, but that changed when I figured out the actual techniques people use.
This article will be a simple-to-follow guide on how to clean and cure your resin 3D prints as the experts do.
The most popular method to clean and cure resin 3D prints is using an all-in-one solution like the Anycubic Wash & Cure. This is one machine which assists in washing a resin print, then emitting UV light to cure it. On a budget, you can use Isopropyl Alcohol to wash and a UV station to cure.
Cleaning and curing resin 3D prints is something that demands a decent amount of attention and attending to. This article will break down the whole operation so you can grasp the concept better and effectively post-process your 3D prints at the end of the day.
What Does Curing Resin 3D Prints Mean?
Before getting into the best ways to clean & cure your resin 3D prints, let’s go over what is really happening in this process, and other key things to be clued-up on.
When you’ve finished printing a resin model, you’re not finished at all, rather your model is now in what’s called a “green state”.
Curing your resin 3D print means that you’re about to unlock the print’s full mechanical potential and complete its polymerization reaction.
Not only are you going to maximize the quality of your prints, they’re ultimately going to perform better as well. This is why curing is extremely essential in SLA 3D printing and amounts to the finalization of the whole process.
What curing really refers to is the mechanical properties of the print. I keep mentioning the term “mechanical” because we’re talking about the actual hardness of the print here.
Curing makes sure your prints are hardened properly and incorporates a stiff finish. Scientifically speaking, curing leads to the development of more chemical bonds in the print, making them very strong in turn.
The element that triggers the process here is light.
That’s not all there is to it, however. When you combine heat with light, you get an additional boost in the curing process.
In fact, it’s exhaustively understood that heat kicks off the optimal curing process, so we can see from here how it’s so important.
There is a range of ways that you can do this. Options range from curing with sunlight to whole UV chambers, which we’re going to discuss later on in the article from top to bottom.
Another reason why post-curing is necessary that you should know about is how it negates oxygen inhibition during the process.
The gist of it is, when you’re printing your model, oxygen tends to accumulate inside the outer surface, making the curation time-consuming and difficult.
However, when you cure your model by letting it rest in a bath of water and letting UV rays or sunlight hit it directly, the water barrier that has been formed allows curing to happen faster.
In conclusion, you can’t expect to make your prints outstanding and quality-driven if you don’t take your time in curing it with appreciable regard. As the points explained, curing is key when it comes to making good prints look amazing.
What Safety Do I Need for Resin 3D Printing?
Truth be told, resin 3D printing might pose a health risk far greater than any other form of 3D printing, may that be FDM. This is because there is a liquid resin involved which can be harmful when not handled appropriately.
Nevertheless, when the curing part has been done and dealt with, you’re out of the danger zone. But, when curing is still yet to be done, you’ll have to be careful not touching your model barehanded.
Before we get into more, you’re going to need the following items to ensure SLA printing remains safe for you.
- Nitrile gloves
- A face mask
- Safety glasses
- A spacious, uncluttered worktable
When working with resin prints, it’s always best to stay one step ahead of the game and strategize your 3D printing.
While that can help you out in several printing aspects, for instance print quality and whatnot, let’s focus on the safety part for now.
The Nitrile gloves are what you’re going to be using before doing anything. Appropriate protection is severely recommended.
To talk about uncured resin, you’re only going to start dealing with toxic stuff from here on out. Therefore, you can estimate how essential it is to be careful at all times.
Uncured resin can quickly be absorbed into your skin, and some people have gotten burns from that same uncured resin spot being in the sunlight, which sets off a chemical reaction.
It’s pretty dangerous stuff if not handled correctly!
Also, try not to let your uncured resin print touch any surface as that’s only going to worsen the conditions for you.
If you do get it somewhere, like the handle of the printer or anywhere on your worktable, clean immediately with IPA and make sure of a rigorous cleansing wipe.
A spacious worktable is what’s going to cover you in case something goes wrong, which is quite an adequate possibility considering the type of printing we’re working with.
It’s a good idea to have some kind of tray underneath your SLA printer to protect your workspace and floor, keeping things secure and organized.
The risks are something to be wary about, but credit where it’s due, the level of quality SLA printing produces is worth it all.
Nevertheless, another important measure to proceed with is to use safety glasses and this is why.
It’s undoubted that you’re going to handle Isopropyl Alcohol (IPA) and uncured resin. A mix of both in the air can get nasty.
Your precious eyes could use a little shielding here. Safety glasses could prevent the hazardous odor from irritating them.
Here’s a video by Makers Muse that details very well on the topic.
Best Ways How to Clean & Cure Resin Prints
Assuming that you’ve taken your print off of the build platform gently with a spatula or a dedicated scraper blade that slides in nicely underneath, the following will guide you to clear and cure your resin prints productively.
Cleaning Your Resin 3D Prints
Without proper cleaning of resin prints, you can experience a whole host of imperfections such as artifacts, surface powdering, pooling and much more.
When your 3D print comes fresh out the printer, you’re going to observe how uncured resin still resides in numerous places on the surface. We’re going to fix this.
As it is covered with this unwanted, unappealing resin, we’re going to have to get rid of this to proceed any further. Let’s start with rinsing and washing.
So, there are two ways that can happen:
- An Ultrasonic Cleanse
- Isopropyl Alcohol Bath or Other Cleaning Solution
The first method is generally more expensive and less common, but it sure has its surreal benefits. First off, you’re going to need an Ultrasonic Cleaner which you can purchase from many places online.
If you have a medium-size resin 3D printer, then a normal ultrasonic cleaner can work really well for you. I’d recommend the LifeBasis 600ml Ultrasonic Cleaner from Amazon which is highly rated and has many professional features.
This model has a 600ml stainless steel tank which is more than you need for regular resin 3D prints. The great thing here is that you can also use it for tons of household items and your favorite jewelry such as watches, rings, glasses, and much more.
The ultrasonic core generates serious energy at 42,000 Hz and has all the necessary accessories such as a basket, watch support and a CD holder.
Get yourself a device that can give you a professionally cleaned look, and improve your resin 3D printing process.
A 12-month warranty is always welcome, but the many certifications that this cleaner holds really drives home the reasons to add the LifeBasis Ultrasonic Cleaner to your arsenal.
For a larger SLA 3D printer, a great ultrasonic cleaner would be the H&B Luxuries Heated Ultrasonic Cleaner. This is 2.5 liters of industrial cleaning power, with many safety features and controllers to ensure amazing results.
Some people use a cleaning agent with their ultrasonic cleaners, but even just clean water works really well.
You can fill the tank up with water than place your resin print in a plastic zip-lock bag or Tupperware filled with either IPA or acetone. This makes it a lot easier to change the liquid once it gets polluted with resin.
Uncured resin mixed with IPA can be pretty dangerous if care is not taken, and can even carry resin through the air which can affect your lungs, so make sure to wear a mask.
Here’s a really cool video of a large-scale ultrasonic cleaner at work!
The second method is what many of the 3D printing community recommends and works pretty well as a budget solution and that isopropyl alcohol or some other cleaning agent.
For the resin that’s latched onto your print’s surface, a thorough rinse that’s repeated two times at best does the trick because IPA is no joke. It works effectively indeed, but it isn’t matched by the Ultrasonic Cleaner.
Spending about three minutes with the alcohol bath is satisfactory enough. Your handling should be swift so that you can cover the whole print.
People’s go-to container for small resin 3D prints is the Lock & Lock Pickle Container from Amazon, simple and effective.
So when you’ve got the cleaning part down, you’re good to go for the next step. Reminder: You must have your Nitrile gloves on at all times during the rinsing step.
IPA can be quite harsh to work with, so below is an alternative and I’ve listed some more alternatives along with a video near the end of this article.
You can find the Mean Green Super Strength Cleaner & Degreaser from Amazon, a very loved product for resin 3D printer enthusiasts.
The method to get your resin 3D prints nice and clean here would be to have a small tub ready with hot water to dunk your prints into right after they are off the build plate.
What this does it ‘melt’ the supports without damage to the print and also lifts excess resin in the process.
You can then give your resin print a quick 3-4 minute bath with Mean Green, then also give it a quick scrub with a soft toothbrush in warm water (can also add dish soap for extra cleaning properties).
If you are tired of the manual work, you can also get an all-in-one solution which I’ve detailed below, after the curing section of this article.
Continue with Support Removal
The next step is to remove your added support items with either a model cutter or a flush cutter, both ways work fine given that the manipulation is unhesitating.
Some might recommend that you could always remove the supports after you’re done curing your print, but generally speaking, you’re better off if you do this in the beginning.
This is because supports that are cured are naturally hardened strongly. When you try to take them off then, the process might be damaging and you might end up compromising the print quality.
Therefore, it’s nothing but optimum to remove the supports right after you’re done with cleaning the part.
If your print can take a hit or two in terms of quality and texture, you can easily remove the supports by hand and not worry about the few imperfections that are left behind.
However, if you’re keen about the intricacy, you’ll have to proceed with caution. Using a model cutter, take off the print by gripping from its tip.
This usually bodes well for the 3D printed part, but there’s another way you can increase even more quality when doing this.
And that, is by leaving a little part which is usually the stud of the support tip. Anything that’s left out can be post-processed using a sandpaper of fine grit, so not even a single mark is left behind using support items.
Curing Your Resin 3D Prints
Coming down to one of the most key steps, curing with UV light is what’s going to provide charm in spades for your print. There are a number of methods this can be done, so the following is an overview.
Get a Professional UV Curing Station
You can go right for the ready-made solution for curing your resin 3D prints by getting yourself a professional UV curing station. Many people get machines like these and get some really great results.
I’d recommend the one made by ELEGOO called the ELEGOO Mercury Curing Machine.
It has many features:
- Intelligent Time Control – has an LED time display which allows you to easily control curing times
- Light-Driven Turntable – your resin prints can easily absorb UV light and rotate within battery
- Reflective Sheet – the lights can reflect nicely from the reflective sheet within this machine for better curing effects
- Two 405nm LED Strips – fast and even curing with the 14 UV LED lights throughout
- See-Through Window – easily observe your 3D prints during the curing process and prevent UV light affecting leakage
Curing for about 5-6 minutes mostly does the job, but if you’re not satisfied, let the print cure for a few more minutes.
Build Your Own UV Curing Station
That’s correct. Countless people today opt for building a whole curing station themselves instead of purchasing an authentic one. This cuts back on the cost, and even turns out to be the perfect alternative.
Here’s a gem of a video where the YouTuber explains how he made an inexpensive UV curing station all by himself.
Use Natural UV Rays from the Sun
You could always refer to one of the world’s most natural resource for this ordeal. Ultraviolet radiations are best know to come from the sun, and here’s how you could let it cure your part for you.
All things considered, this option may require you to wait a little extra, but the outcome is surefire appreciable.
You can either dip your print in a bath of water and let it post-cure, or just get it under the sun all by itself.
Efficient post-curing with the sun may take up to 15-20 minutes. This time is based on an estimate, so you can always evaluate the quality yourself by checking your print constantly.
Best All-in-One Solution to Clean & Cure Resin Prints
The Anycubic Wash and Cure Machine (Amazon) is something that does it all without the average-grade consumer ever having to dive deep into the post-processing mechanics themselves.
This handy machine supports several resin 3D printers and features a potent 356/405 nm UV light set. The unit is deemed optimal for the Anycubic Photon printer series, of course, coming straight from the manufacturer, that is.
This all-in-one washing and curing machine comprises a very responsive and fluid touch button, and two built-in modes.
This YouTube video explains the working of the Anycubic Wash and Cure Machine. Take a look at it below.
Wash Mode is truly versatile and is highly user-friendly, while the Cure Mode consists of different ranges of UV wavelengths to make a striking difference.
In summary, both of these modes attribute to a ton of functionality and deliver an amazingly painless post-processing experience.
For the curing and washing time, the machine takes around 2-6 minutes and gets everything sorted out for you.
It also packs a compact washing container where all the work takes place. Additionally, there’s a suspension bracket the height of which, can be optimized in accordance with the fluid level in the container.
There’s an Auto-Pause function too. This automatically occurs when the machine detects that the top cover or lid is not in place and has been taken off, thereby halting the UV light cure instantly.
The curing platform can fully rotate up to 360° so all of the angles of the printed part gets exposed to the directly-hitting UV light.
Physically, it’s a robust looking machine with stainless steal bearings. Sitting on your worktable alongside your printer, we doubt it’s not going to catch someone’s eye.
You can get the Anycubic Wash & Cure for a very competitive price from Amazon today.
What to Do If My Resin Prints Still Smell?
If your prints still smell after you’ve cleaned them with IPA and the curing has been done as well, there are a bunch of things you can try out that you may have missed.
First off, it’s obvious that SLA printing involves resins and usually isopropyl alcohol for cleaning purposes. Both of these, unfortunately, aren’t odorless and can make any environment unlikable with their smell.
Moreover, when the print job is small-scale, this problem doesn’t become that much of an issue. However, for extensive work, it does become something to take care of as prolonged periods of resin 3D printing contribute to the fumes in the air.
This is why we recommend printing in an appropriately ventilated area with a functional exhaust fan somewhere. This makes your surroundings much more tolerable and okay to be in.
The following are some more factors to attend to.
Check for Hidden Uncured Resin
This is quite a common occurrence as a multitude of people take their time meticulously cleaning the resin part, but it’s often that they miss the hidden uncured remnants.
This goes on to become the major reason of smelly printed parts after you’ve cured them. Carefully check for any uncured leftovers on the inner walls/surfaces of your print and clean them promptly.
Analyze How You’re Curing Your Parts
In some places, the UV index might be insufficiently low. This means that the sun might not be able to cure your resin printed part properly and with a great effect.
Try using a proper UV curing station that consists of a dedicated UV cure mechanism. This does the trick in many cases as well.
This factor especially becomes eminent when the model you’ve printed is solid and not hollow. The UV light from the sun may only be powerful enough to cure the outer surface, but couldn’t reach the inner parts.
This is why the post-cure process should be given importance and be dealt with in similar fashion.
How Long Should I UV Cure Resin Prints?
3D printing is an area where you only improve with consistency and unflinching awareness. As time passes and you become more of a veteran, everything starts to appear in a different picture and you become able enough to take certain decisions yourself.
The recommended time for UV light curation of resin prints in a proper station is around 2-6 minutes. Not satisfied with the result? Hold it in for a few more minutes.
How Long to Cure Resin Prints in the Sun?
When it comes to the sun, make sure that the UV index is acceptable so the job is fairly well done. Just because the sun is shining, doesn’t mean the type of UV ray that we need is high enough.
Subsequently, you’re going to have to show a bit more patience with this method depending on the UV levels and maybe wait around 15-20 minutes.
Then, there is the Anycubic Wash & Cure Machine that cures the print for around 3 minutes all by itself.
Can You Over Cure Resin Prints?
Yes, you can over cure resin 3D prints when you are using intense levels of UV light on an object, as well as from leaving it out in the sun. A UV chamber delivers much more UV exposure, so you don’t want to leave 3D prints in there for a lot longer than necessary.
Many users have reported that leaving their resin 3D prints on the window sill for a few weeks causes small features to easily shatter, and say parts definitely become more brittle.
Other reports have stated that a low level of UV exposure shouldn’t affect the mechanical properties of a resin print.
Although there are many conflicting pieces of information about resin prints, UV, and changes in mechanical properties, I think it can vary quite widely depending on the resin quality, level of UV, and design of the model itself.
Temperature is another factor that comes into play when talking about the curing of resin, where higher temperatures allow better UV penetration of dense parts of a model and speeds up the curing process.
The science behind this is that higher temperatures lower the barrier for of needed UV energy to complete the photo-polymerization process.
UV irradiation results in material degradation, especially because they are organic and can be damaged by UV exposure.
High levels of UV exposure can lead to resin parts degrading which is where those reports of brittle objects come from. You won’t get the same extreme level of UV exposure from sunlight than you would from a professional UV chamber.
This means you are a lot more likely to over cure a resin object using, for example, the Anycubic Wash & Cure at high UV levels versus UV exposure from the sun. Basically, you wouldn’t want to cure a resin part overnight.
What Can I Use to Clean Resin Prints? Alternatives to Isopropyl Alcohol
The main reason why isopropyl alcohol is used is mainly due to being a poor solvent that dries quickly. It does well in seprating the liquidity of the resin from the solid parts of your 3D print.
Basic alcohols like Everclear or Vodka work really well because you usually don’t need to dry them off, making it more convenient for this task. There isn’t a special chemical reaction that takes place to properly clean your resin 3D prints.
If you can’t get access to isopropyl alcohol, specifically the 90% version, there are other solutions you can use for your resin 3D prints.
The following are what many other people have had success with:
- Mean Green
- 70% Isopropyl Alcohol (Rubbing Alcohol)
- Simple Green
- Mr. Clean
- Acetone (smells pretty bad) – some resins don’t work well with it
- Denatured Alcohol
Methylated spirits are used by people, but these are essentially IPA with additives, making them even more toxic to humans. They do work, but you probably want to go with an alternative.
A better choice would be to actually change your resin to water washable resin which would make your job a lot easier.
I’d recommend the ELEGOO Water Washable Rapid Resin on Amazon. Not only does it have really high ratings on Amazon, it cures fast and has great stability to guarantee a worry-free printing experience.
Can You Cure Resin Prints Without Washing Them?
Yes, you can cure resin prints without washing them, but this can be a safety issue with some models that have resin on the inside. Uncured resin inside complex models may leak out after curing. Resin prints that are cured without washing feel tacky to the touch, and have a glossy sheen look.
Washing resin models takes care of the uncured resin inside, so if you don’t wash it, it may leak out after curing. Simple models with no gaps can be cured without washing them for a shinier look.
For most resin prints, I’d recommend washing them with a good cleaning solution like isopropyl alcohol.