Will a 395nm UV light cure resin?

UV resin is a type of hardening resin that cures when exposed to UV light. It can be used for making jewelry, crafts, and more.

It is often used for making molds for small parts. It requires far less exposure time than other types of resins, which makes it popular among hobbyists and artists.

In order to cure the resin, you need to expose it to a UV light that falls between the range of 300-400nm (between violet and blue). There are some UV lights that have LEDs that emit within this range, but they are far less common than those with LEDs outside this range.

Will a 395nm UV light cure resin?

Will a 395nm UV light cure resin

If you have a 395nm flashlight, then you have a resin-curing light! The only difference between the 395nm and 405nm lights is that 395nm does not cure as well or as fast as 405nm.

The good thing about the 395nm curing light though is that it may work for faster curing resins since you don’t need to worry about the light reflecting off of any pigments in your resin.

This will allow the UV light to reach down into your deep wells more efficiently and cure your resin faster. If you use a 405 nm curing light on some fast curing resins they may start to bubble up in just a few minutes due to how hot they get when being cured under UV light.

So, if you’re using fast cure resins or ones with lots of pigment (like glow-in-the-dark), then using a 395 nm flashlight is probably best.

However, if you’re using regular slow cure resins like SeeThrough clear casting resin or SeeThrough Strong clear casting resin which cures at 60 seconds per 0.1″ (3mm) thickness, then I recommend using the 405 nm flashlights.

Will any UV light cure resin?

As discussed in the previous section, any UV light can cure UV resin if it lies within the 400 to 500nm range. Think of this as a band of radiation – with the lower end being at a lower frequency than the high end.

Anything outside of 400 to 500nm is not capable of curing UV resin by itself.

The intensity of the UV light is important, but so are exposure time and distance between your resin and your curing light source.

If you’re using a 100mW/cm2 intensity light from 10cm away for 1 second, that wouldn’t be enough to cure your resin. But if you were using that same UV light from 2cm away for 30 seconds, that would be more than sufficient to cure your resin.

The amount of energy produced by a given 365nm or 405nm lamp is more than enough for most resins – some resins require more intense lights (higher wattage) but these are typically filled with materials like carbon fiber or metal powders which increase opacity/reflectivity and therefore decrease transparency/ability for UV rays to penetrate through your part very easily.

How many watts do you need to cure UV resin?

How many watts do you need to cure UV resin

Most resins are either 365nm or 395nm. You can use a 365nm light to cure 395nm resin, but the curing time will be significantly longer.

The same is true if you try to cure 365nm resin with a 395nm light—it won’t be as fast. Many lights come with both wavelengths, so there’s no need to worry about making a mistake when picking one out.

The amount of power your lamp puts out also matters. If you have an LED lamp that runs on batteries, you’ll definitely want to opt for the faster-curing resin because it will take forever!

A UV light with 3 watts of power at even 355 nm is going to get the job done in minutes instead of hours or days and it might even lead you towards new adventures in jewelry design where otherwise you would not have ventured!

Is 365nm or 395nm better?

In the 405nm wavelength range, a UV light will still cure resin, but it’s a specialized wavelength that is rarely seen in UV curing lamps. It’s also dangerous for your eyes.

If you’re looking to cure resin with a 395nm light source, you need to be aware that it can cause eye damage, as well as skin damage if you are exposed over a long period of time.

You should also know that 395nm is not the same as 365nm; 395nm refers to the peak emission spectrum (the color intensity), and 365nm refers to the centerline in this spectrum (the color).

The difference between the two wavelengths is small enough that most people who use these terms interchangeably are not being inaccurate; however, if you want to get technical they are slightly different.

What wavelength is used to cure UV resin?

The answer is no. UV resin cures in the exact same way as a gel polish—so if you’ve ever used a gel polisher, this will make sense to you.

If you haven’t, that’s okay! The important thing to know is that the wavelength of light used to cure the resin matters more than its wattage.

UV resin cures with light in the 365nm range, which means that 395nm lights are not ideal for curing it (i.e., they’ll work but won’t be as effective).

Because of this, there are some resins on the market that won’t cure or will only cure a little bit when using these types of bulbs.

LED lights generally provide better coverage than fluorescent bulbs because they emit less heat while they cure; however, most UV nail lamps aren’t designed for curing UV resin and can only fit one finger at a time.

This means you may have to reposition your hand several times during the curing process, which can lead to incomplete curing and sticky surfaces on your pieces when finished.

If you do decide to use an LED lamp (for any type of UV curing), keep in mind that higher wattages and closer proximity offer better results.

Can I use a UV light for epoxy resin?

Can I use a UV light for epoxy resin

You may be wondering if a UV light will cure epoxy resin. While you can use a UV light to cure epoxy resin, it might not give you the results you are looking for.

Epoxy resin requires more wattage than UV resin to cure. If a customer was using this method I would recommend them to try with only one layer of epoxy and then check on the curing process every 15 minutes until complete.

The other issue with curing epoxy with a UV light is that the epoxy could come out sticky, or take hours to completely cure.

Will a black light bulb cure resin?

  • The answer is no. Black lights produce a type of UV light (UVA), but not the specific wavelength you need to cure UV resin. While both emit ultraviolet radiation, black lights are designed to also emit visible light, giving them their signature glow. A true UV light source does not create visible light and will therefore appear dark or be housed in an opaque shell.
  • Black lights are used to make fluorescent materials glow. These include things like tonic water, highlighters, and certain clothing accessories (think fluorescent beads). The mix of UVA and visible light makes these objects easier to see in dim lighting environments like bars or clubs. This makes black lights a popular choice for parties as well as for inspection purposes—for instance, checking money or documents for authenticity.*

Why is my UV resin sticky after curing?

Why is my UV resin sticky after curing

There are so many variables involved here that it’s really hard to give you a definitive answer. To start with, did you use any additives like mica powders, inclusions, or anything else? Those can all affect the curing process of your resin.

Depending on how many of those you used and if they contain UV inhibitors or not, that could be the reason why your resin is sticky. Were you making a larger piece? If yes, then it might need more time to cure thoroughly especially if it’s thick.

I will list out some possible reasons and offer some suggestions on how to fix the problem…

  • Could it be the resin?

If you are using different resins from different brands and only one is giving you problems, this might be due to a difference in quality between them.

The first thing I would do is stick to one brand of resin for now until we have figured out what the root cause for your sticky resin is.


The question I set out to answer was, “Will a 395nm UV light cure resin?” The answer is that it can, but the results are less than ideal.

The result is better than leaving it in direct sunlight for over an hour, but still not great. If you have access to a 405nm UV light, I highly recommend getting one instead of using a 395nm.

If you don’t want to spend any money at all and you have some patience, then use direct sunlight to cure your prints.

If you don’t mind spending $20-30 on a cheap 405nm printer for resin printing then do that instead!

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Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

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