Calculate RPM when changing pads
Written by: Vinnie van Rooij
In some cases, you feel comfortable with a certain speed (rpm), and feel that this works best with a certain product. However, not all your pads are the same size and you want to know what speed setting you need to maintain the same speed.
Contents
Why maintaining the speed
Not all pads are the same size, which means that the outside of the pads does not always spin with the same speed. We can demonstrate this with a simple example.
Let’s say that we have a wheel that makes 20 turns every minute. The wheel has a diameter of 20 inches.
The circumference of this wheel is (diameter * π) 20 * 3.14 = 62.8 inch. Which basically means that the wheel would travel a distance of 62.8 inch when it spins 1 time. Seeing as the wheel spins 20 times a minute, we can calculate that it would travel 20 * 62.8 a minute. This comes to: 1256 inch (104 feet 8 inches). The outside of this wheel spins with a speed of 1256 inch per minute.
Now we take a wheel that spins with the same speed, but it has a diameter of 10 inches.
The circumference of this wheel is 10 * 3.14 = 31.4 inch. If you add the amount of spins per minute to this, it comes to (20 * 31.4) 628 inch (52 feet 4 inches). We can therefore conclude that the wheel spins with a speed of 628 inch per minute. Even though the wheel makes the same amount of spins per minute, the speed on the edge is very different.
Calculate the speed of your pad
Lets say that you are using a wool pad that has a diameter of 16 centimeter. You want to use another foam pad that is 12 centimeter in diameter. You are going to use the wool pad with a speed of 1800 rpm (read the manual of your polisher to see what setting matches what rpm).
The formula would be:
rpm * diameter = speed
For the wool pad this comes to: 1800 * 16 = 28800 centimeter per minute.
For the foam pad, the formula would look a bit different, seeing as we only know we want to keep the same speed. So it would look a bit like: ??? * 12 = 28800 centimeter per minute. To fill in the ??? we need to turn the formula around, which would become: 28800 / 12 = ???. The answer would be: 2400.
To use the foam pad with the same effective speed in comparison to the foam pad, the rpm should be set to 2400 when using the foam pad.
- For removing defects with the Kevin Brown Method we first apply a massive amount of the finishing polish on the pad and massage it in. This is to prime your pad properly, so that the product covers the hole face of the pad. ...
- Farecla is a manufacturer of detailing products located in Hertfordshire, United Kingdom. The company has a range of products aimed at refining and perfecting surfaces in several different ways....
- Gumming can occur when polishing with not enough lubrication, to much heat and a clogged pad. It will show up as sticky residue marks on the paintwork. It is a general indication of an incorrect polishing technique. Ignoring this issue will negatively affect your polishing result....
- When you polish a surface, the level of imperfection defines how much work it will be to achieve a perfect finish. This can either be a 1 stage polish, a 2 stage polish or even a 3 stage polish. Different types of stages needed define slightly what pads and/or polish you are going to need, and might give an indication of the time-frame needed....
- Paintwork can, in some cases, become oxidized. Making it turn matte and slightly fade color. If untreated, it can eventually cause the lacquer and/or paintwork to completely fail. It is most common on red cars, but it can happen with every color....
- A Dual Action polisher is a polishing machine that uses a circular motion combined with a spinning motion to create a rational double action. This motion is useful when polishing a surface by machine. The Dual Action polisher is famed for being easy to work with, making it ideal for beginners....
Links to this article
There are no external links to this article. Yet.