Buffing Omega Concrete Countertop SealerTM to increase its sheen
Omega Concrete Countertop Sealer is designed to cure to a low sheen. It’s not quite matte/dead flat, but it’s duller than a satin or semi-gloss finish. Increasing the sheen of the cured Omega finish is straightforward and uses readily-available tools and materials commonly used in the automotive industry.
First, Omega must be well cured for the best results. Omega can be polished as soon as it’s sandable, but only a moderate sheen will develop. For a higher gloss, it’s recommended that the finish cure for at least 4 days at room temperature to achieve the best results.
- Variable speed rotary polisher, or a dual action polisher.
- Hook & Loop Rotary Flexible Backing Plate.
- Wool or foam compounding and a polishing pad.
- Swirl-removal or polishing compound.
Bear in mind that these tools and materials are designed for and sold to the automotive industry. They are mainly used to improve the surface appearance of automotive paint and are thus readily available from reputable suppliers catering to that industry.
Polishers are power tools that can quickly increase the sheen of cured Omega when used with the appropriate polishing pad and polishing compound. There are two basic types of electric polishers: rotary and dual action.
A rotary polisher is a powerful tool that spins the polishing pad in a clockwise circular motion, just like a diamond polishing disc is on a wet polisher for concrete. Coupled with a wool pad (more on that later), a rotary polisher can easily buff and polish curves and challenging shapes. Variable-speed is necessary to regulate the rotational speed to minimize heat build-up and control the cutting/polishing intensity. Generally, polishers have speeds that range from around 600 rpm up to about 3000 rpm. The typical speed range used is around 1000-2000 rpm for most applications. Rotary polishes take patience, skill and practice, as the polishing head needs to be continuously moved to apply even polishing action. Polishers are fast, but they can easily damage a finish if used incorrectly. Too much speed, too much pressure, too steep of an angle, a firm pad and compound that is too aggressive all can damage the finish, leaving streaks, haze, dull spots or even worse.
Dual action polisher
Dual action polishers are much more forgiving than rotary polishers, yet are still very effective. Dual action polishers are characterized by the motion of the head. It spins on a central spindle, and this spindle rotates around an eccentric offset. This creates a semi-random pattern that minimizes swirl marks and dramatically reduces the chance of damaging the finish. Dual action polishers tend to be more controllable as the cutting action is less intense, and thus slower than a rotary polisher. They are often variable speed. However, the benefit is a more even, swirl-free sheen that involves less risk to the finish. They can’t remove scratches like a rotary polisher, but dual action polishers can take a flat finish and give it an even sheen without much effort.
The backing plate is the interface between the polishing pad and the electric polisher. Backing plates usually have a 5/8”-11 pitch thread, which is standard on most North American polishers, and often are hook-and-loop faced, allowing for easy and rapid polishing pad changes. Generally the backing plate is sized for the task at hand. Larger backing plates (6” and 7”) are for larger 8”-10” wool pads and 7”-8” foam pads used on larger areas, and smaller backing plates (2” to 4”) are for smaller, or more difficult to reach areas. Backing plates should have a thin, flexible edge to allow for polishing curves. A hard backing plate can apply too much pressure to the edge of the bonnet or pad, resulting in sealer damage.
Compounding and Polishing Pad
The compounding and polishing (C&P) pad is charged with polishing compound and rotated by the polisher to act on the sealer. C&P pads can be made of wool, wool blends, or various densities of foam. Some C&P pads are designed only for rotary polishers, while others can be used on either rotary or dual action polishers. Polishing pads attach to the backer plate with hook-and-loop fasteners.
Wool pads are for aggressive, fast cut action. They’re only meant for use on rotary polishers. Wool pads are thick and can easily conform to irregular surfaces, but can also focus aggressive cutting action on edges and sharp corners, potentially damaging the surface. Wool can create a great deal of friction and generate intense heat build-up, so greater care is needed when using this type of pad.
Wool pads come in twisted and fluffy, straight-fiber versions. Twisted wool pads have a more aggressive cutting action, useful in skilled hands, but dangerous to your finish in inexperienced hands. Both tend to shed lint, and fluffy wool pads tend to clump and get easily matted.
Foam polishing pads eliminate many of the drawbacks of foam: they can be used on dual-action polishers, they don’t generate as much heat, and, foam polishing pads come in a wide range of firmness levels and sizes to regulate the cutting action. Generally, firm foam pads are for aggressive cutting, while softer foam pads are for polishing to a high shine. It’s recommended to start with a firmer pad to start and switch to a softer pad for a higher shine.
Foam pads come in sizes ranging from 1” to 8.5” in diameter, with 6” to 6.5” pads being the most common size. Generally, a 6” pad uses a 5” backer plate.
Polishing compounds are abrasive liquids applied to the polishing pad that abrasively increase the shine of the Omega sealer.
Cutting compounds are the most aggressive type of polish and should be used only as needed. Compounds are commonly used on severely neglected vehicles and to clean up marks left by wet sanding. Compounds will almost always leave behind some marring, hazing, or holograms and should always be followed up with a finer polish and pad combination.
Cutting polishes are less aggressive than compounds regarding cutting power and usually do not finish down as well as a finishing polish. For a higher gloss, it is recommended to follow up a cutting polish with a finishing. Some cutting polishes break down as they are used, and thus are capable of finishing down to create a higher gloss.
Finishing polishes are meant for gloss development and typically will not remove imperfections deeper than a very light swirl. Because they are relatively non-aggressive, a finishing polish used on a firm foam pad will achieve a low luster.
How to Polish Omega
- Ensure Omega is well cured for at least 1-4 days after sealing.
- Remove any dust motes and surficial roughness using fine sandpaper (320). Often a light pass done by hand using old 320-600 grit sandpaper is all that’s necessary to knock off any rough areas that are caused by dust in the finish. The surface should feel smooth after sanding.
- Clean the surface to remove any debris. A clean microfiber cloth wetted with water works well.
- Select a polisher, polishing pad and compound appropriate for the task. Start with the least-aggressive combination of polisher, pad, and polish to get the results you want. Dual action polishers are recommended over rotary polishers because dual action polishers spread out their energy over a larger area because the buffing pad orbits as it spins. Their cutting action is less aggressive, giving you more control. Select a medium firmness cutting foam pad, because it’s less aggressive than a wool pad or a hard-cutting foam pad. And start with a cutting polish, as it will be less aggressive yet still bring up a soft shine. Additional gloss can be developed using a softer pad and a finer polishing compound.
- Start at a slower speed, and work methodically, keeping the polisher moving, and spending equal amounts of time everywhere. Avoid focusing on one spot, or spending too much time in one area, as variations in sheen can occur. The idea is to evenly increase the gloss level everywhere so that the piece looks uniformly shinier. Increase the polisher speed as necessary, ensuring the surface gains gloss and does not show signs of damage from excessive polisher speed.
- Avoid edges, corners and hard or sharp areas, where the polisher could wear through the finish, or the polisher could catch the edge and cause damage.