It is never that hard to achieve a mirror finish on raw stainless steel. However, the process can be time-consuming and tedious. If you are patient enough, the result will be worth it.
There are many ways of polishing stainless steel, and this article describes the easiest and probably the most effective method. The two methods of polishing stainless steel described in this post involve the use of a mini-grinder and a bench grinder with 750W.
You can start polishing stainless steel using a standard low-cost 350W bench grinder and still achieve better results. However, if your amount of polishing is high, you will need to upgrade to a more powerful machine. The 750W bench grinder is not as expensive as you may think.
Polishing stainless steel using a bench grinder is by far the most effective way. What you need to understand is that a low powered bench grinder may not give you the desired finish. You should use at least a 350W model for the work.
Additionally, the grinder should be one that allows the removal of the grinding wheel to allow the fitting of a pigtail to the shaft. This is a supplementary shaft with spiral threads onto which mops are fitted.
If you cannot access a mini-grinder or a bench grinder, then you can use a powerful hand drill with grinding discs to polish stainless steel. The hand drill has to be fitted with a shaft-like disc in the chunk of the drill. This method of polishing stainless steel can also be used to polish old, scratched, and stained fittings.
If you want to make a specific trim, you can get stainless steel from your dealer. 304 is the best for trims even though some people also prefer 316 stainless steel.
Whatever gauge you choose, there will be no difference in the work you want to polish.
How to polish stainless steel step by step
Step 1: Preparing the strip or angled steel
If you have a flat bar of steel straight from the shop, you will realize that it has some rough, mottled finish. This is what you need to ground off first to give the metal a base finish before you start polishing.
For this stage, you need a mini-grinder. Start with the coarse flap disc to remove the rough edges, and then use a finer disc to remove the deep scratches. Alternatively, you can use a drill and flap disc to get the job done, but expect it to be slower.
After the first grind, your stainless steel will have a flat surface with some scratches because of the flap disc used.
To remove the scratches left by the flap disc from stainless steel, you will need Abracs discs starting from the coarsest to the finest.
As you progress from one step to the other, you will realize that a surface shine is appearing. If you have removed all the scratches, then your stainless steel is ready for polishing. If some scratches are remaining, then you need to repeat the process over and over.
Step 2: Preparing Stainless Steel Sheet
If you have a wider area to polish, you will realize that the grinder is digging deep into the surface. For stainless steel, you may need a 3-inch dual action air sander or an electric sander.
Start with the coarsest 60-grit abrasive and proceed using finer versions 180-grit, 320-grit, and lastly 400-grit. The 60-grit will give your stainless steel a matt brushed finish, while the 180-grit and above produces a dull shine.
After the 400-grit, proceed to 3000-grit disc, which is designed to produce a high-quality finishing. This disc is usually wet, so you need to be cautious when using an electric sander.
Step3: Final Polishing With A Wheel
For this step, you require a 750W grinder even though the 350W grinder can also be useful. You also need a hard sisal wheel with a black polishing compound and a soft cloth wheel with a white polishing compound.
Start with the hard sisal wheel and the black polishing compound that you will need to apply on the wheel as it spins. Work the stainless steel up and down or side to side as you continue applying more polishing compound.
After you are done with the hard sisal wheel, then transition to the soft cloth wheel and white polishing compound to give stainless steel a final finish.
When you are through the two processes, you will realize that stainless steel has a polishing compound stuck on its surface, which prevents it from shining. You need to remove this compound using a metal polish like Solvol.
Using the 3-inch sander with a woolen buffing pad, clean the stainless steel to get the final finish, which is a highly polished and reflective surface.
PRO TIP: It is essential to check that all scratches and marks are removed at every stage before proceeding to the next step. This helps to save time and avoid having to retrace your steps later when you should be finishing.
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This article has provided a step by step guide of how to polish stainless steel. The process should not be a hard task if you are patient to follow every step and have the necessary tools. Always remember to ensure that you have the desired result after every step before proceeding to the next. Additionally, your safety should be a primary concern. Always ensure that you have protective gear like goggles, protective earbobs, and gloves. Besides, you should be cautious when using electric grinders. Wipe off any moisture from the working surface to prevent electric shocks. Otherwise, you should find polishing stainless steel a very straightforward process.
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