A closet knob, UV resin and jewelry concrete: one builder's kicker rail method

Here is the sequence exactly as the builder describes it, with the reasoning behind each stage.

1. Pick your rail. The rail is a closet knob. The post doesn't say what the knob is made of or what shape it is, and that matters: whether it's metal, plastic or wood decides how trucks behave on it (more on that below).
2. Set it in a mold. The knob goes into a mold that will become the base. The builder hasn't described the mold's size or material.
3. Fix it with UV resin. A layer of UV resin is poured and cured to "fixate" the knob, in the builder's word. This step stops the rail from floating, tilting or shifting when the heavier concrete goes in.
4. Fill with jewelry concrete. The rest of the mold is filled with jewellery concrete, which gives the kicker its weight and its "sturdy" feel.
5. Demold and clean up. The builder called the first result "a bit messy," so expect some tidying of edges and surfaces.

For curing either material, follow the instructions on the product you buy. The post doesn't give times, and different resins and concretes vary.

These aren't answered in the post, but they decide whether your version actually rides well.

The rail surface

A fingerboard rail lives or dies on how trucks slide across it. A smooth metal knob will usually grind; a painted, plastic or wooden one may stick. If yours grabs, a bit of wax on the contact surface is the usual first fix.

Scale against your deck

Knobs come in all sizes. Hold your board against the knob before you commit to a mold, and check that the rail's height and length suit a 32–34 mm deck and the tricks you want to do on it.

The kicker angle

A kicker rail needs a ramp-up into the rail. The post doesn't explain how the kicker shape was formed, so plan your mold so the concrete surface carries the board onto the rail cleanly.

The concrete surface

Concrete finish affects how wheels roll and how boards slide off. A rough top is fine for pop but can chew up graphics; a smoother finish is kinder.

• Skipping the fixing layer. The resin step exists so the knob stays put. Pouring concrete straight around a loose knob risks a crooked rail.
• Not checking scale. A knob that looks right in the hand can be oversized next to a fingerboard.
• Ignoring the rail finish. A sticky coating turns a grind rail into a stall bar. Test it, wax it, or pick a different knob.
• Expecting a perfect first pour. The builder's own first attempt came out messy; that's normal for a first cast.
• Guessing cure times. Use the manufacturer's guidance for both the resin and the concrete.

Read u/mainlymoltencheese's original post and look closely at the photo for the shape of the base and how the knob sits. If you have questions about their mold or materials, the comments on that post are the place to ask, since those details aren't in the write-up.

If you try it, start with a small mold and a cheap knob, and treat the first one as a test piece. Once you know how your resin and concrete behave, the second cast is where you dial in the kicker angle and the finish.