[Katherine Swift]

This question comes from Oliver:

Hi,
I have some oak tree stumps I plan to use to make small side tables out of. I want to cast them in resin and the look im aiming for is similar to the picture attached:

[Katherine Swift]

HI Oliver,

What a beautiful project! I would like to ask you a few questions first:

Do you have a mold for this project?
What is your experience with resin?

[Oliver]

Hi I am a joiner mainly making tables and small furniture. I don’t have any experience with casting resin so there will be some trial and error.
I planned to make a mold out of melamine laminated particle board coated with a mold release.
Any advice you can provide would be a huge help!

[Katherine Swift]

Since it’s going to be furniture, I would suggest using a polyester casting resin. It will cure very hard and will allow you to polish it with a buffing compound and polishing tools. Unfortunately though, polyester resin isn’t something I recommend for beginners. Here’s an article on why: https://resinobsession.com/resin-resin-resin/polyester-casting-resin

I would suggest starting with a smaller project, getting to know the ins and outs of the resin, then moving onto to a bigger project like this.

[Oliver]

Thank you for your response. I will experiment a bit first with some smaller projects.
Do you have any specific advice on a larger casting? Obviously it will need to be a huge amount of resin cast in multiple layers. Can witness lines be sanded/polished out?
I assume the tree stump will need to be kiln dried?
What would be the best way to avoid bubbles? The stump will be too large for any pressure or vacuum vessels.

[Katherine Swift]

For a casting this large, there is going to be a lot of heat generated. I mention that because in order to minimize lines, you will need to pour the next layer while the first layer is in the gel stage. If you decide to use polyester resin for this project, you will need to add a little less hardener with each layer to account for the extra heat.

Yes, the tree stump will need to be very dry before placing in the resin. I would then suggest coating it with at least two coats of a clear drying acrylic based spray. Otherwise, trapped air will come out into the resin.

With a casting this large, avoiding bubbles is going to be tricky. The best advice I can give you is to mix your resin carefully to avoid them to begin with. A heat gun is good for getting the bubbles to pop.

https://shop.resinobsession.com/collections/tools-and-supplies/products/wow-embossing-heat-tool

The tough part is going to be with the amount of resin you pour at once. The larger your pour, the less work, but the harder it is going to be for bubbles to rise to the surface and pop. More layers means you will have an easier time getting the bubbles out, but more work mixing and pouring, etc.

[Jennifer Dillon]

I am attempting to turn some palm trees into a table and plant stands for my lanai. I don’t need the resin for beauty in this project but simply to seal the fiberous, soft core and prevent rot in the stump. Each stump will be receiving a slate top. What would be a good resin for this project and what do I need to keep in mind? I do not have experience with resin.

[Katherine Swift]

Hi Jennifer,

Any of the doming resins in our store will work for this project:
https://shop.resinobsession.com/collections/resin/doming

You need to make sure the stump is completely dry and sealed first. Otherwise, trapped air will escape into the resin and cause bubbles. The resin will also not stop rot which is why it needs to be dry first.

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