Types of Metal Polishing Techniques and Their Polished Step

Product engineers commonly utilize various polishing techniques to enhance the surface quality of their metal products. Before discussing the different techniques for metal polishing, let’s check the pre-polishing procedure you should know.

Surface Preparation Before Polishing

Preparing the metal surface to be polished properly before polishing is crucial. Here are some steps to follow for better surface preparation:

• Remove Rust or Corrosion: You must remove any rust or corrosion on the surface of a metal part before polishing.
• Clean the Surface: Eliminate any grease, debris, or contaminant from the metal’s surface using a suitable cleaning agent such as a mild detergent.
• Smooth-Out Imperfections: Smoothen all dents, scratches, and imperfections on the metal’s surface.
• Rinse and Dry: You have to rinse off any cleaning agent, abrasives, or rust removal residue after eliminating all imperfections from the metal’s surface. Wipe off and dry the surface thoroughly to avoid water spots and corrosion.

After being ready for the metal surface, this section explores the step-wise guide to metal polishing techniques.

1. Hand Polishing Technique

Hand polishing is a manual technique involving different polishing compounds and tools. It requires direct contact between the metal surface and the polisher. Although hand polishing consumes more time than machine polishing techniques, it provides personalized, controlled, and precise results. Below are the steps involved in the hand-polishing process:

Select and Apply the Polishing Compound

Choose a suitable polishing compound depending on the type of metal and preferred finish. Typical examples of polishing compounds include jeweler’s rouge, metal polishes, and rubbing compounds.

Start Polishing

Rub the metal surface with a polishing compound in a circular or back-and-forth motion using moderate pressure. Polish continuously until you achieve the preferred level of shine. However, you may need to re-apply the compound as necessary.

Clean and Inspect

Clean the metal’s surface with a soft cloth to wipe off residues of the polishing compound once you have achieved the desired polishing. Also, inspect the part’s surface for any imperfections or areas needing further processing.

2. Machine Polishing Technique

Machine polishing technique uses power tools such as dual-action or rotary polishers. Metal types compatible with this technique include titanium, nickel, chrome, bronze, stainless steel, and copper.

Manufacturers in various industries such as electronics, aerospace, and medical devices usually use machine polishing techniques for desired results.

Below is a step-wise guide for machine polishing technique:

Choose the Right Polishing Pad

Use the appropriate polishing pad depending on the required polishing level. The various polishing pads suitable for machining polishing include wool, foam, or microfiber pads with varying levels of aggressiveness.

Apply the Polishing Compound

Apply a small amount of polishing compound onto the polishing pad. Ensure you coat the pad evenly but don’t overload the metal surface with compound.

Program the Speed and Begin Polishing

Program the machine polisher to the preferred speed. Then, begin polishing by operating the machine in a slow, overlapping motion across the surface of the machined parts. Apply moderate pressure while polishing and avoid polishing one spot for longer to prevent heat buildup.

Check the Progress

Stop and inspect the metal polishing’s progress periodically. Wipe-off excess polishing compound and check the surface for any defects. Replace the polishing pad if required and regulate the polishing pressure and speed.

Complete the Polishing

Use a soft cloth to clean the metal’s surface to eliminate any residue once you have achieved the preferred level of shine.

3. Chemical Polishing Technique

This technique involves using specialized chemical compounds to eliminate thin layers of the metal’s surface, providing an improved and aesthetically appealing exterior. The chemical polishing process is an ideal technique for delicate parts. Here is a breakdown of the chemical polishing technique:

Select a Suitable Chemical Polishing Solution

There are varying chemical solutions available for this technique, depending on the type of metals. Etchants are a primary element in these solutions. It selectively dissolves the surface layer of the metal sheet.

Prepare the Solution

Mix the chemical polishing solution correctly by following the provided instructions. Usually, the mixtures involve diluting the compound with a certain solvent or water.

Submerge the Metal Object

Bathe the metal component in the chemical polishing compound. Ensure the metal component is fully submerged and the solution spreads across the metal surface marked for polishing.

Monitor the Chemical Process

You must be very careful with the chemical polishing of metal components because it is a delicate process. Monitor the reaction of the metal parts with the polishing solution. However, the required time for polishing depends on the metal type and the required outcome.

Rinse and Dry

Rinse the metal parts thoroughly with water after removing them from the solution. Then, dry the moist completely to avoid any water spots or corrosion.