Doming resin casting resin – resin formulas explained

doming resin casting resinWhat’s the difference between casting resin and doming resin?

This difference is important to know for your resin success! Depending on what you want to make, choosing the right resin for your project is important so that you can get the results you want.

Let’s start with a couple of basic concepts

A doming resin mixes thick enough that when you use it, it finishes in a smooth dome on your project. If you think about it like a teardrop, when you drop doming resin onto a surface, it will stay in a domed shape. A doming resin is what you want to use when you want a curved surface to something or if you want to use resin on a surface where there are no sides to keep the resin contained. The surface tension of doming resin will be enough for it to want to stay on the surface.  Note:  The larger the surface, the harder it is to keep resin on that surface, even if it is a doming resin.  

A casting resin mixes in a thinner viscosity. It is meant to be used in something with sides like molds. This thinner viscosity is what makes casting resins ideal for spreading into all the intricate parts of a mold.  You could also use a casting resin in a bezel, but it is not going to have a domed finish.  Casting resins also do not self-level as doming resins do.  This means that casting resins will not level themselves out over a surface.

When would you use a doming resin?

A doming resin mixes in a thicker surface tension and is going to stay on the surface of something without sides. For example, if you want to do resin for artwork, you want a doming resin so that it will (mostly) stay on the surface of your painting.

Doming resins are also important if you want to make jewelry with a domed finish.

Note:  The larger the surface, the less likely you are to keep all of your resin contained, even if it is a doming resin.

When would you use a casting resin?

Casting resins are meant to be used for just that – casting. You should pour them into something that has sides to be able to contain it. They can be poured into deep layers if desired. Since they don’t mix as thick, removing bubbles from this resin is easier compared to a doming resin.

For small jewelry projects, you want something that is going to cure clear and durable.

When making larger projects like sculptures, deep paperweights and river-tables, a slow-curing formula meant for deep pours is an advantage.

Can you use doming resins and casting resins interchangeably?

Yes, but you may not get the results you want. Doming resins are meant to be cast in no more than an eighth-inch depth to allow bubbles to easily escape. You can cast a doming resin in a thicker layer than that, but it is likely to retain bubbles. If you are using a deep or intricate mold, it may be hard for you to get all the bubbles out before it starts to cure.

A casting resin can be applied to a surface without sides, but because it mixes thinner, it will not want to stay as a complete mass. It will continue to spread out and will produce the dreaded ‘fish eyes’.

What should I notice when I’m mixing these resins?

Doming resins will mix to the consistency of syrup. Casting resins will mix more like water. If you create bubbles during mixing, more will escape on their own in a casting resin.

How do I know if I’m buying a casting resin or doming resin?

When you buy a resin, it is going to be one or the other. If it that information isn’t on the packaging, ask! For the resins sold on Resin Obsession, we have that information in a PDF link in this article: resin casting

Can I apply multiple layers of doming resin or casting resin?

Both will take additional layers. You can wait until the previous layer is fully cured before applying the next layer, or if you only wait until the previous layer starts to gel, you can pour the next layer and minimize the lines between them.

If you want to see differences between doming resin and casting resin, this video shows you:

You can buy both kinds of resin here.

Want to learn more about doming resin or casting resin?  Then you will want a copy of Resin Fundamentals.  I explain everything you need to know about resin in clear and concise details.  It’s the book I wish I had when I was a resin beginner!  Buy it now and you can download it in minutes.

Unpublished Blog Posts of Resin Obsession, LLC © 2021 Resin Obsession, LLC

Like this post? You may be interested in  What kind of resin should I use? - Choosing a resin

32 thoughts on “Doming resin casting resin – resin formulas explained

  1. I’ve been trying to coat polymer clay earrings that I put an image on to (baked in) with the doming resin and find that many times when I think I’ve put enough on it starts to pull back from the edges (no rims on the earrings) or leaves a dry spot. If I try to correct this after the resin hardens it doesn’t blend in. Any suggestions? BTW this video is great.

  2. Let’s say I want to add a dome to something that I have cast, can you use a doming resin on top of a casting resin?

  3. I have seaglass, small shells and some pottery shards glued to an old window and want to use resin like grout for the mosaic. I am still not sure if I need doming or casting. I have not used resin before

  4. Why can’t you use some resins on wood? I’ve got a table and the top is timber Pailings with a gap between each one. I know it’s a design feature but it’s not good for crumbs. I want to pour resin into each gap. But I think I’ve bought the wrong product. It’s called Kleer Cast by Norski

    1. Some resins shrink too much after curing and can pull away from the wood. What kind of resin is Kleer Cast? I’m not familiar with that one.

  5. if my resin is gooey after curing time what do I do, or what can I do. I did a 6 pane window with seaglass I want to hang inside but it i hang it will it run?

  6. Hi, and thanks for all the helpful advice above.
    I am trying to make some drink coasters on ceramic tiles. The painting part is fun and works out well. However, I can’t get any resin to go hard enough to withstand a hot coffee cup without getting indentations from the cup base. Even after 2 weeks it still happens. The only doming resin in my local (ie. New Zealand) hardware store is by Norski. I have also tried a casting resin and a clear polyurethane varnish. Any ideas?

  7. Thank you for responding, your answer really helped. I am VERY new to this, but I’m also very eager to expand my creative side with resin! After watching your vid, I also learned that I’m going to have to make a contraption of some sort to rotate the piece (a mannequin head) 180 degrees throughout the process which will be tricky because I need the resin to cover the entire piece, top of the head to the base.

  8. I have mistakenly bought the casting resin to seal artwork. One coat and I see the non coverage. If I put another coat of this resin will it eventually make a smooth coverage? Or do I have to get some doming resin to do the next coat?

  9. I did a 1 7/8″ wide x 1″7/8 H x 3 1/8 long paper weight with Amazing Clear Cast resin. I did the pouring into the silicone mold (I made) in 2 sections. I poured the first mixed portion and waited about 8 hours before I poured the second mixed resin portion. The outside shape came out great and shiny but I had “tons” of very small bubbles. While I was mixing, I put the mixing cup in hot water (from the faucet) to minimize bubbles. I also used a butane candle lighter on the surface to also pop any air bubbles that came to the surface. After 10 minutes in the mold, I use a few light spritz of spray of isopropyl alcohol, again to pop any bubbles that came to the surface. I read about using a fire torch or a candle flame lighter, the warm/hot water in a bowl and the spray of alcohol from various readings and videos, and I did all these. But I still got “tons” of tiny bubbles – help!

    1. Hi Teresa, I’m sorry this happened to you. Because of the mixing thickness of the Amazing clear cast resin, it likes to hold onto bubbles. It’s very difficult to get a bubble-free casting when using this resin in pours of greater than 1/8 inch. Instead, one of our clear casting resins is a better fit. For pours of 3 ounces or less, the Resin Obsession super clear resin is what you want:
      For pours of 3 ounces or more, the Resin obsession deep pour casting resin works great:

  10. Hi! I want to use clear doming resin to seal shrinky dinks. They have irregular shapes, and they’re also typically decorated with either colored pencil or alcohol marker.

    Is there anything I need to do to protect the designs? What do you recommend for a beginner?

    I included a link to my products. I currently seal them with embossing powder, but find it can cloud the image a bit.

  11. I am currently making epoxy resin cheese boards,the problem I have is that the epoxy only leaves a very thin layer on the sides with very little I need a thicker epoxy resin?

    1. Hi Wayne, unfortunately, it’s the nature of epoxy resin to drip off the sides. While a thicker resin will help, it’s not going to be as thick as the top of your cheeseboard.

  12. Hi!
    Does anyone know if this Casting Resin turns yellow over time?
    I love working with Polyester resin because it’s harder, never goes yellow, and has less bubbles then Epoxy… but I also wanna try something different.

    I’m worried about the yellowing… Does anyone know about it?

    Thank you!

    1. Hi Isabelle, unfortunately, all resins, whether polyester or epoxy, will yellow over time.

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