Are you ready to upgrade your orbital sander but aren’t sure if you should buy a dual-action or random orbital model?
When you need to tackle tedious sanding jobs, having a quality power sander in your tool kit is invaluable.
To get the best sanding tool for your projects, you need to understand the differences between a dual-action sander and a random orbital sander.
Luckily, I put all the information you need right here in this guide where you’ll find:
- What type of sander these are
- What projects they are good for
- What a dual-action and random orbital sander is
While many assume these two types of sanders are the same, they are not. So, stick around and get the details about each type of sander so you can shop with confidence.
What Type of Sanders Are Dual-action and Random?
Both dual-action and random-orbital sanders are a version of a standard orbital sander but have more features to achieve better results in complex sanding projects.
What projects are these sanders good for?
Both DA and random-orbital sanders are great for paint stripping, rough stock removal, rounding edges, autobody metal and paint, and ultra-smooth finishes on metal and wood.
What a Dual Action or DA Sander Is
A dual-action sander (commonly known as a DA sander) has one mode that locks the sanding pad to spin in a flat-plane circle. The second mode moves the pad using an internal bearing, which gives the head a bit of a wobble and creates less friction against the surface.
This dual-action feature provides the user with more options to complete sanding projects. Locked rotation action allows you to cut through material fast (but will leave swirl marks) since you can push down firmly without stopping the disc from spinning. Switch to the orbital motion to create a smooth finish.
What a Random Orbital Sander Is
Random orbital sanders have one mode. The round sanding disc spins, but also creates a random elliptical motion which keeps the sanding pad from hitting the same area twice.
This random orbiting feature keeps the sander from leaving swirl marks in the material and floats across different wood grains with ease.
Main Commonalities and Differences Between DA and Random Orbital Sanders
Dual-action sanders are a favorite for rough autobody work and serious construction projects. Most dual-action sanders are pneumatic, but you can purchase electric versions. A dual-action orbital sander is ideal for:
- Grinding down sharp edges and rust
- Flattening down wood planks
- Sanding rough Bondo/putty
- Stripping many layers of paint
Random orbital sanders are typically electric which makes them easier to use about the home and garage. The random spinning/wobble of the head allows you to create a fine finish with no swirl marks when working on:
- Paint or varnish stripping
- Woodworking projects
- Sanding down wood flooring
- Autobody detailing
Choose the operation mode (standard or random orbit). Attach sanding disc to pad. Grip the handle and start the unit.
Once the pad is spinning at top speed, carefully press the sander to the surface. You can apply pressure to one place to reduce material quickly in the standard mode or move it around for overall smoothing in the random orbit mode.
Random orbital sanders
Attach sanding disc to pad. Turn unit on and let the disc spin at full speed before you place it against the surface. Grip the top of the sander in your palm and immediately move the sander across the surface using gentle downward pressure. Pushing down too hard can stop the head from spinning.
Keep the disc flat to the surface to prevent divots. Only tip the unit when rounding off edges and corners.
Dual-action sanders cost between $30 up to $450. The price rises as size, speed, and power increase. The average cost of a quality 5-inch DA sander is about $60-$80.
Random orbital sanders cost as much as $650 for a direct-electric professional-grade model. While random orbital sanders are available for as low as $29, the average cost of a good 5 or 6-inch random orbital sander is around $75-$100.
The cost of a multi-pack of sanding, buffing, or polishing discs run between $10-$40.
Both DA and random orbital sanders are available with a 5-inch, 6-inch, or 8-inch disc size and weigh between 2-4 pounds. Most are ten inches or less in length.
Dual-action sanders tend to be longer than their random orbital counterparts due to the handle. You can buy DA sanders with a palm grip if you want to save on storage space.
Random orbital sanders have a more compact size since you use the top of the sander to control the movement.
Strength of Sander
Dual-action sanders mainly run off powerful air compressors, which give them the strength to sand through tough material. Most have variable speed options from between 2000-10,000 RPM (rotations per minute).
Random orbital sanders are usually electric, which provides a steady stream of power to the unit. The orbital action has the strength to achieve an ultra-fine finish when sanding down wood, metal, or paint. Some models can reach speeds of 12,000RPM. At high RPM, the motor that sits under your hand can get hot, making the unit hard to hold.
For those who do automotive body repair or lots of home improvement projects, a DA or random orbital sander is a must-have.
I hope this guide highlights the difference between a dual action versus a random orbital sander, so you purchase the right tool to handle your needs. Pneumatic or electric, the perfect dual-action or random orbital sander is waiting to make those tiresome sanding tasks much more enjoyable!