In this Hometalk tutorial, I show you how to put seashells in resin. Also, learn the best resin to use to seal seashells in order to reduce bubbles, how to properly mix resin, and much more. So, let's get started. Be sure to visit my blog and subscribe to my YouTube channel for free DIY tutorials & handmade items.
How to Put Seashells in Resin
I included a video in this tutorial to serve as a supplement to the written tutorial. The written tutorial is more detailed than the video, so I encourage you to read the written tutorial and refer back to the video as needed.
Luckily, I live a short walk from the beach where my family and I collect seashells while doing other beach activities such as paddle boarding and snorkeling. If you don't live close to a beach or unable to collect seashells, there are many places to purchase them online. I included a link in the tools section of this post. I work with resin quite often and I learned there is a resin more suitable for seashell crafts.
While this project can be done with all types of epoxy resin, choosing the correct resin will save you time, frustration, and money. I work with resin quite often and I learned there is a resin more suitable for seashell crafts. To simplify, there are 2 types of resin. Actually, there are many, many more but there are 2 commonly used for DIY projects. The rest are beyond the scope of this article.
- Epoxy Resin for Thin Pours 1:1 mixing ratio.Cures within 24 hours.Very Dense.Can only be poured up to 1/8" to 1/4" thick.
- Epoxy Resin for Deep Pours 2:1 mixing ratioCures slowly depending on thickness of pourVery thin.Can be poured up to 4" thick
Seashells come in many shapes, sizes, and textures. Most importantly, the various shapes and porous surface of seashells may trap air and cause bubbles when set in resin. As a result, I prefer to use deep pour epoxy because:
- Thinner epoxy penetrates the porous surface and tiny holes better. In turn, better penetration means less bubbles and a stronger bond.
- Deep Pour epoxy cures slower which helps it form a stronger bond.
Again, there is nothing wrong with using epoxy resin for thin pours as many resin artists use this type of resin. In fact, it does offer a few benefits such as quicker cure time. I recommend deep pour epoxy based on my experience from using both types for various projects.
Now that you chose the type of resin you will use, it's time to determine how much you need. Resin is not cheap, so determining the amount you need for your project is an important money-saving step. To make this simple, I included a free resin calculator download on my website so that you can use it over and over again on your personal computer, tablet, or phone. It's absolutely free, so be sure to download a copy.
The formula to determine the gallons or quarts needed is as follows: Gallons: (L*W*H) * .004329
Quarts: (L*W*H) * .017316
I'll briefly explain how to get the numbers to plug into the formula: Measure the length, width, and height of the area resin will be used in inches. Measure in inches b/c the formula is based on cubic inches. Multiply the length x width x height to convert the area to cubic inches. Then, multiply this number by the numbers above to get gallons or quarts. The total amount of resin I needed for this project was 3 gallons. (47*10*1.5) * .004329 = ~3 gallons.
Use the total amount of resin needed for the project and divide that number by 2. This will give you enough resin to fill the area halfway in order to set the seashells (more on this in a later step). In my project, 3 gallons divided by 2 = 1.5 gallons. I mixed the resin according to the manufacturer's instructions. Most epoxy looks cloudy at first. Eventually, it turns clear when properly mixed and ready. As a quick tip, use 3 containers when mixing epoxy resin for accurate measurements and proper mixing. Trust me, it is well worth the money to use 3 containers. In fact, most epoxy resin manufacturers recommend it. Essentially, I use each container for a different purpose when mixing epoxy resin.
- First Container: Part A
- Second Container: Part B
- Third Container: Mix Part A and Part B.
If you want clear resin, skip this step.I like to add color or glow powder to the bottom layer of my projects, but sometimes I don't. If you want to add pigment powder or dye, now is the time to do it.
Pour the epoxy into the area and check for leaks. After pouring, you may need to remove air bubbles with a mini torch or heat gun for 5 to 15 minutes after the pour.
IMPORTANT - Before setting shells in resin, allow the epoxy to cure about 30%. Some shells float to the surface if set in place before the epoxy pour. Or, shells sink to the bottom if set in uncured epoxy.By allowing the epoxy to cure 30%, the shells slightly sink and form a bond. I prefer to suspend the shells in the middle of the resin rather all the way on the bottom or top. I check the epoxy by touching it with a stick on one end. Once the resin slightly adheres to the stick, I know it’s time to set seashells. Essentially, a small string of resin follows the stick when removed.
As you can see, the glow powder adds a nice touch to this project.
Once you place the shells in the resin, they should sink a small amount. This is what you want as it will make the next steps easier.
Choose the shells from your collection to set in resin. Next, place the shells in the resin in a random pattern to resemble a beach or ocean shore.
To further prevent air bubbles if using thick epoxy, I recommend using a foam brush to apply resin to the exposed shells. I find it easier to do this immediately after the previous step so the cure times match. However, it works just as well to seal the shells before starting this project. Some people prefer to use fast setting epoxy to seal the shells before the project. Again, different strokes for different strokes. I encourage you to do whatever you feel most comfortable with. Keep in mind, I did not seal the shells in this project and had no issues with bubbles b/c I used deep pour (thin) resin.
Before pouring the second layer of epoxy, make sure it is cured enough for the second layer. Different epoxy resin may have different instructions on additional layers.
Thumbprint Test: I recommend to use the ‘Thumbprint Test’ before pouring additional layers of epoxy. In other words, the epoxy should be soft enough to leave a thumbprint. If the epoxy sticks to my thumb, I allow it to cure a bit more before embedding seashells in epoxy resin. However, if the epoxy is too hard for a thumbprint, I know I need to lightly sand the surface before applying a final coat.
Mix the second half of resin (192 ounces in my case) and pour the epoxy over the shells very slowly. I find I create air pockets if I pour the epoxy too quickly when embedding seashells.
Fill the area with resin completely and monitor the resin for 15 minutes to remove any bubbles that may rise. Allow the project to cure in a dust free environment.
This was a fun project and I'm happy I finally finished the seashell desk my daughter wanted for her room. She absolutely loves it - I just hope it doesn't distract her while doing homework. :). Be sure to visit my blog for more DIY tutorials and handcrafted, beach inspired items.