Created with Sketch. Created with Sketch.
Fundamentals of Random Orbit Sanding

Fundamentals of Random Orbit Sanding

Posted by Klingspor's Woodworking Shop on Oct 5th 2021

References for Bare Wood Sanding Applications

Klingspors Woodworking Shop Principles of Sanders

1) Principles of Sander

Sanders are a power tool that helps smooth and level the surface of wood. Wide range of sizes and shapes are available, but the process stays the same. Keep an RO Sander flat as this allows you to use all of the abrasive on the disc not just the edges.

Klingspors Woodworking Shop Heavy Stock Removal

2) Heavy Stock Removal

When surfacing down rough wood, it's referred to as heavy stock removal. Belt sanders are the most common portable power tool for this task. Typically 24-60 grit is used when you want to flatten your project.

Klingspors Woodworking Shop Use the Correct Tool

3) Use the Correct Tool

Angle grinders are meant to be used at an angle, hints the name. These should only be used when shaping wooden sculptures or leveling welds. Your Random Orbit Sander is not an Angle Grinder so keep the RO sander flat, and the angle grinder at an angle.

Klingspors Woodworking Shop What is Random Orbit

4) What's Random Orbit?

A random orbit sander both oscillates and orbits. Oscillation is the process of moving back and forth in one linear planar direction, while orbiting is spinning in a constant circle. When you mix these two together you get a random pattern that is harder to see in your finished surface than an oscillating pattern.

Klingspors Woodworking Shop Riding the Sander

5) Riding the Sander

Biggest mistake in sanding, pressing down on the sander. Let the weight of the sander (Machine) allow the tool (Abrasive) to do its job. You cannot make a 220 grit act like a 120 grit by pressing harder. This slows the sander down, causing adverse swirls and improper scratch pattern.

Klingspors Woodworking Shop Do Not Skip Grits

6) Don't Skip the Grits

This isn't to sell more sandpaper, it's the proper way to sand. Do not skip more than 1 grit in a sequence. If you start with 80, (skip 100) then 120, (skip 150) then 180 on bare wood, this is a base sanding sequence. We advise not to sand with only 80 and 220.