Have you recently purchased or printed a plastic hidden blade, only to feel that the raw plastic texture is too overwhelming? Does it lack that cold, mechanical steel look from the games?

Once players acquire a 3D-printed hidden blade, many discover an exciting new way to level up their gear: Post-processing and painting.

With the right techniques, you can transform an ordinary PLA blade into what looks like a razor-sharp steel weapon. Today, this guide will walk you through the professional painting process for your plastic hidden blade.

Tool Checklist

Before you begin, gather the following "gear":

Sandpaper: 400, 800, and 1200 grit.

Primer: Grey spray-can surface primer.

Metallic Paint: Silver, Gunmetal, or Chrome.

Weathering Wash / Diluted Black Paint: For creating wear and shadow effects.

Masking Tape: To protect mechanical parts that should not be painted.

Step 1: Sanding – The Foundation of Texture

For most 3D-printed parts, layer lines are often visible on the blade surface. If this is the case, do not apply paint immediately, as it will result in a rough, "cheap" finish.

Start by rough-sanding obvious ridges with 400-grit sandpaper, then gradually move up to 1200-grit for wet sanding until the surface is ultra-smooth. Note: Do not over-sand the sliding mechanisms or slots, as this can change the tolerances and cause the blade to jam.

Step 2: Priming – Improving Paint Adhesion

Next, apply an even coat of Grey Surface Primer. Do not skip this step! Primer enhances the adhesion of the subsequent color coats to prevent peeling. It also acts as a "check-point" to help you spot any surface imperfections that still need sanding.

Step 3: Base Coating – Giving it a Metallic Soul

Wait about 24 hours for the primer to dry completely before applying the main color.

First, apply a layer of Matte Black as a base, then lightly spray Silver or Gunmetal at an angle.

Professionals use the "multiple thin coats" method to prevent paint buildup, which can interfere with the mechanics.

Step 4: Dry Brushing & Weathering – Killing the "Plastic Look"

Dry Brushing: Dip a brush into a small amount of bright silver paint, wipe off the excess on a paper towel until the brush is nearly dry, and lightly "flick" it over the edges of the blade. This simulates the "white edges" caused by metal-on-metal friction.

Weathering: Apply highly diluted black paint (a "wash") into the crevices and gaps, then immediately wipe the surface with a cotton swab. This leaves the "grime" in the cracks, giving the prop depth and history.

Step 5: Clear Coating – Durable and Play-Ready

Hidden blades are meant to be handled. Since sweat and friction can easily damage the paint, apply a thin layer of Semi-Matte (Satin) Clear Coat to protect your work.

Pro Tips: Avoiding Common Pitfalls

Protect the Mechanics: Before spraying, always use masking tape to seal off the springs and the internal sliding tracks. Excess paint inside the mechanism is the #1 cause of deployment failure.

Safety First: Always work in a well-ventilated area and wear a protective mask to avoid inhaling paint fumes.

Patience is Key: Let every single layer dry completely before moving to the next. Haste makes waste!