Let’s start with materials we have on hand.

Episode 2: Let’s Get Started with Everyday Materials

You can begin mold polishing with things you already have around you

What this article wants to convey

• You can start polishing even without specialized tools.
• Try experiencing the basics of polishing using easy-to-find materials.

1. What you can and can’t do with everyday materials

What you can do

• Practice stepping up through finer grits using sandpaper and stick stones on a practice piece.
• Practice removing small dents and scratches.
• Practice keeping your sanding/stoning direction consistent.

What you can’t do (for now)

• Mirror finishing (I want to be able to do this eventually.)
• Shapes that require high dimensional accuracy.
• Deep damage that requires welding.

2. “Everyday materials” checklist (easiest to get first)

Tools

• Sandpaper (e.g., #180, #240, #320, #400, #600, #800, #1000, #1500, #2000, etc.)
• Felt or T-shirt scraps (for wiping)
• Backing blocks
• Disposable chopsticks or bamboo skewers
• Aluminum square stock
• Square wood stock, etc.

Clog prevention / protection

• Machine oil
• Parts cleaner
• Protective tape or masking tape (for masking/protection)

3. A basic process you can start today

Step 1: Check the area to be polished

• Identify the area you will polish.
• Check how rough the surface is.
• Mask off surrounding areas with masking tape (so you don’t polish where you shouldn’t).

Step 2: Prepare the sandpaper

• Start with a slightly coarser grit.
• Guideline examples (a table in the article would be helpful):
  • Noticeable scratches → #240 to #400
  • Light scratches → #600 to #800
  • Smoothing/conditioning for finishing → #1000 to #2000

Step 3: Basic polishing technique

• Change the sanding direction by 90° (or 45°) as you progress.
• Use a backing block so the paper contacts the surface evenly while you sand.
• For corners, modify the backing block so it can reach the corner properly.
• Use parts cleaner or anti-rust spray to prevent clogging; anti-rust spray also helps the sandpaper slide smoothly.

Step 4: When to change to the next grit

• When the sandpaper starts to lose resistance, it’s time to move to the next grit (e.g., #320 → #400).
• Don’t skip grits (e.g., don’t jump from #320 → #600).

4. Tips by area: polishing with everyday materials

Flat surfaces

• Press the backing block (chopstick/skewer, etc.) evenly.
  • If the backing block isn’t flat/even, the polished surface can become wavy.

Corners / edges

• Hold the backing block perpendicular so you don’t round over the edge.

5. Common mistakes

• Polishing with only your fingertips can make the surface wavy.
• Skipping grits (if the base surface isn’t properly prepared, scratches will show through even with fine paper).
• Focusing on the same spot too long and creating a hollow.
• Not keeping the backing block straight, causing edges to get rounded (“washed out”).

6. Checking the finish

• Use a metal polish to check (e.g., Pikal).
• Run your finger across the polished area.
• Shine a light on it and inspect.
• Use a magnifier to examine the surface.

8. Summary (short)

• Even with everyday materials, you can improve by learning how to use backing blocks and sandpaper properly.
• Don’t keep polishing the same spot over and over.

Images of the everyday tools will be added in order.

団まごめ

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