Random Orbit Sanding Speeds

[Frank Berryman]

Boy am I a newbie. After doing some research here and online I picked up a Milwaukee 6021 ROS. I am ready to sand. It has six speeds. I have no clue which speed to select. Is it by grit? Any guidelines. Thanks in advance.

[Chris Padilla]

I've always run mine at the highest settings but it all depends on how much control you need over your ROS.

This is often dictated by the size of the surface you are sanding. If it is a large flat surface, max it out. If it is a small surface where most of the ROS isn't touching wood, you may want more control so run it slower.

[Ray Dockrey]

I have the Ridgid 5" VS ROS and I have never used the variable speed. I tested it when I got it but that was it. I am not sure if the VS even still works. When I have to get another one I won't spend the extra to get VS.

[Mike Henderson]

There are times when I'm sanding and don't want to be as aggressive as full speed - for example, when sanding some veneer - so I use the lower speeds. But most of the time, I use it full speed.

Usually, I find the sander not working well, and realize I had turned the speed down and forgot to turn it back up to full speed.

Mike

[glenn bradley]

I tend to use lower speeds on finer grits. Generally, full speed up to 220 grit. Then, depending on what I'm doing I will slow down for higher grits. Just to be confusing I will run low speeds with 220 if I want good stock removal but a bit more control.

[Michael Schwartz]

According to a Porter Cable engineer I talked to a while back who worked on the initial design of Random Orbit Sanders they are designed to be moved very very slowly along the surface.

Lowering the speed would allow you to maintain a slow speed when sanding thin materials such as veneers/plywood but lower the material removal so you don't sand through.

99% of the time I run my festool sander full speed.

[Cole Dunlay]

If you're removing a film finish such as paint or poly you'll want to slow the sander down. The slower speed prevents the finish from "melting" and clogging the sandpaper. Also, if you're sanding small pieces it helps to slow down the pad as it gives you better control.