Ekasand electric sanders are great for a number of reasons, including the ergonomics, brushless motors, internal fan system to keep it cooler, portability and of course, the option to run the sander at various RPM’s. The Ekasand sanders offer a range of speeds from 4,000 to 10,000 RPM for 5 & 6” random orbital sanders, and 4,000 to 9,000 for 3×4” sheet sanders.
Given the option of using this tool at various speeds, and that most people want to get their sanding done as quickly as possible, you might be wondering why you’d want to lower the speed of the sander. Well, in this article, we’ll go into the thought process for what speed to choose for your application.
Heat – The Enemy of Sanding
Firstly, the most common issue in sanding – specifically with electric sanders – is heat generation. Heat is a problem because it leads to loading, which leads to a bad, uneven finish and lower lifespan of your abrasives. Not to mention, if your sander gets too hot, the built-in protection would kick in to automatically power off the tool, thereby preventing overheating of the internal components. While this is a safety feature designed to optimize the life of the tool, it can be incredibly frustrating while in the process of sanding, as it can completely interrupt your flow and productivity.
As you can see, heat is the enemy of sanding, yet it is nearly unavoidable due to the nature of the friction and the motion involved in sanding, as well as the rotation of the motor in the machine. Additionally, putting too much pressure on the sander will lead to more heat, versus letting the weight of the sander do the work, a problem that inexperienced operators often deal with.
Luckily, there are some things we can do to minimize heat and prevent these negative outcomes – one of which is utilizing the various RPM speed options built into the sander.
A Note about Random Orbit Disc vs 3×4” Sheet Sanders & Speed
While both of our electric sander types, sheet and disc, offer the options for variable power/speeds, our experts recommend that for most woodworking applications using the 5 and 6” random orbit disc sanders, operators stick to 10,000 RPMs, as slowing down could contribute to sanding swirls, and there unfortunately isn’t much that could be done to prevent this outcome when sanding wood with slower RPMs on these sanders. On the other hand, these sanders can be slowed down on solid surface and when using polish and a polish pad.
When it comes to the 3×4 sheet sanders, because the rotation is not a random pattern as with a 5”or 6”, the 3”x4” does leave swirl marks when running a coated abrasive. To mitigate these swirl marks, simply use a pad saver between the coated abrasive and the back up pad.
Like with the 5” & 6” sanders we do not recommend slowing the sander when sanding on wood when using a coated abrasive. We do however see an advantage when using a foam back abrasive, slowing the sander to sand sealer can assist in less cut through.
Why run the sander faster?
Uneeda’s electric sanders offer speeds up to 10,000 RPM, which is great for most woodworking applications, particularly if the user is not pressing too hard on the sander. In the majority of circumstances, our sanding experts recommend setting and leaving the sander at the highest speed, while, of course, using proper technique and pressure.
Using faster speeds has both some advantages and disadvantages. Firstly, using a faster speed and proper technique will allow for a faster sanding job, so less time spent sanding! The higher RPMs will also provide a more aggressive sand, so it would be good for rough sanding applications, such as stock removal, stripping paint or rust, and more. The higher speeds can also be used for finishing applications, if you are adept with the sander, however too much pressure or too aggressive sanding can lead to issues like cut-through or flat-spotting.
The disadvantages of the higher speeds would mostly relate to the likelihood for heat generation, leading to a sander that is hot to the touch, in addition to loading and the associated problems. Also, it can be more difficult to control the sander at higher speeds, particularly for operators with less experience.
Why sand at a slower speed?
While it may seem counterintuitive to sand at slower speeds, especially since most people want to get sanding done more quickly, it may be a wise choice to choose a lower RPM in certain circumstances.
For instance, using a lower speed could be helpful when doing projects that require a finer attention to detail, such as sanding thin materials like veneers, where over-sanding/sanding-through can quickly become a problem. Additionally, using the slower speeds could be helpful on finishing applications, such as sanding between coats of finish – particularly for stain/lacquer and sealer, where it’s important to not sand through the coating. Further, when sanding ornate edges, curves and profiles, a lower speed could be helpful to avoid flat-spotting or changing the shape of the piece.
In addition to these fine sanding applications, where it will be easier to control the sander at lower speeds, when sanding materials prone to melting, such as polyester, plastic or film, using a lower speed can be helpful to reduce heat, thereby preventing clogging.
The main disadvantage to slower sanding speeds is that it could take slightly longer to sand your piece. In addition, a caveat is that slowing an orbital sander down can contribute to the creation of sanding swirls, so it’s important to pay attention and use proper lighting to make sure your surface is smooth after sanding.
The Ekasand electric sanders offer a speed range from 4,000 to 10,000 RPM. While most people want to finish their sanding faster, and would therefore prefer to max out the RPMs, it can sometimes be beneficial to slow down the machine. The main problem we are looking to avoid is heat generation, which could lead the sander to shut down, work piece materials to melt and abrasives to load. The second most important thing to consider is the ability to control the sander, which can be easier at slower speeds. Therefore, it can be helpful to slow down the RPMs when sanding materials prone to melting and loading, such as plastics, and in applications that require more attention to detail and finer control of the sander, such as thin materials like veneer.
Our sanding experts are available to answer your questions at email@example.com.