Building a Flagstone Base

For the small (30 mm) bases I'm using Hirst Arts Flagstone Floor Tile Mold #260 . The squares are 1", plenty to cover the 21 mm or so that the floor of the base has

For the medium and large ( 40 mm and 50 mm) bases, I'm using Large Flagstone Mold #265 . The squares are 1.5", which is more than enough for the 40 mm and almost enough for the 50 mm.

After mixing up enough Apoxie to fill the number of squares that you want to cast (always mix more than you think you'll need), take a large paintbrush (a cotton swab will work too) and dip it in water. Then dab it into the squares you're going to fill. You don't need much, just a small bead of water in each stone recess.

Now press the Apoxie into the cavity. Don't be too concerned about getting into the corners, as those will be cut away to fit inside the ring. You don't need to fill the entire depth either, but make sure you're over halfway for sure.

Now because you're pressing into the mold there will be a bit of distortion vs. pouring a liquid. (I mention this because I'm sure someone will try to use this method for doing terrain and then wonder why their tiles aren't lining up exactly.) Once the mold is filled, you'll need to let it cure for at least 3 hours on average. You can speed this up a bit by setting the mold under a warm desk lamp. (Heat kills silicone though, so don't get it too close or you'll wear out the mold prematurely.) Ideally, let it cure naturally overnight. When the Apoxie has set, flip the mold over and pop out your new flagstone tiles.

Now take your base ring and lay it over the top of the tile to get an idea of where to cut. I'm doing a 50 mm base here as my example as they're the trickiest ones. I've cut off the corners until it fits inside the ring.

Looks good so far, right? Well, check the profile view.

Because the Apoxie was pressed in instead of poured as a liquid it's going to be rough and uneven on the underside. You'll need to file / grind away at it until it lies flat. This takes a bit of practice but it gets easier if you do it enough times.

Once the tile is nice and level inside the ring, it's time to fill and attach it. In the past, I've used green stuff for this part. Recently though, I've been using more Apoxie. It's much stronger and more durable than green and it will stick to the plastic base ring as well.

I start by adding small lumps in the missing sections.

I press these into the gaps. Take care not to distort the plastic ring while doing this. It's easy to do. Once the gaps are filled I smooth out the Apoxie with a wet finger and pull some over the already cured tile. Apoxie bonds to itself very well so this makes a seamless piece once it cures.

Now turn the base over and look at the areas where the Apoxie squished up to fill the gaps. Take a sculpting tool and carve some lines in those areas to blend them into the rest of the base. When you're satisfied set it aside and allow it to cure. Finished.