How to polish a metal flooring like the one in this image?
The product is known as Aluminum Diamond Plate.

Sadly it is going to take some work and if you can, rent a commercial floor buffer, or expect to spend a lot of hours and your hands and knees. Which would still require at least a hand held buffer. (Choice of hand held or commercial floor buffer should be based on square footage and accessibility.)

Taking Care of Aluminum Diamond Plate
Like any other type of high-use metal, it is important to take good care of your aluminum diamond plate to help keeping it looking and working great. Because it is used for such demanding purposes, chances are good that it will get quite dirty on a regular basis. Below is a basic guide on how to clean aluminum diamond plate.

Step One: Cleansers
Do not ever use harsh detergents or floor soap to clean diamond plate. Don’t allow water or cleaning products to sit on the surface for a long period of time. Harsh chemicals will eventually destroy the finish, as will acid-based cleansers, detergents and compounds, when used improperly. Non-detergent car wash soaps are your best choice. Wash and then rinse thoroughly right away to prevent staining, water spots, blemishes or etching on the surface.

Step Two: Protection
A protective coat of wax will help to keep your diamond plate looking new, regardless of whether it is aluminum, steel or stainless steel. Regular waxing will help to preserve the diamond plate and reduce the amount of time required to clean it on a regular basis. Start with clean diamond plate and evaluate the condition of the aluminum diamond plate to see how much wax and correction needs to be done to get it looking shiny and new.

Step Three: Correction
In some cases, it takes more than clean diamond plate and some wax to get your metal looking new. You might need to use specialized metal cleaners or polishes, as well as a buffer to get it back to its original shine. Buffing and polishing will take a lot of time and effort, so make sure you set aside enough time to get the job done. You don’t want to leave any cleaners or polish on the metal longer than the manufacturer’s recommendations suggest.

Preventative Maintenance for Aluminum, Steel and Stainless Steel Diamond Plate
Sometimes the best way to clean diamond plate is to never really let it get out of hand in the first place. The next part of our guide to proper care and maintenance of diamond plate is a series of tips that you can take that will help to reduce the amount of time required to clean and care for the metal on a regular basis. Establishing good habits like these will help you to take even better care of your aluminum diamond plate than ever before.

More can be read here: http://midcitysteel.com/proper-care-maintenance-of-aluminum-diamond-plate/

Here is a link to a product called Marine 31. It has good reviews and great results. https://www.amazon.com/Marine-31-Heavy-Cut-Oxidation-Cleaner/dp/B00CMHJMVM

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