Bowl Sanding Tools are somewhat simplistic. How those bowl sanding tools are used to get the best looking bowls can seem overwhelming at first.
I’ll tell you straight out: I used to hate sanding. I dreaded the idea of “wasting time” and wanted to get on with doing other more important things. Sanding and I have come to agreeable terms over the years. We get along fine now, and the results are satisfactory for both of us.
Who really enjoys sanding? I was that way. The thrill while turning and seeing a beautiful wood bowl emerge from a chunk of wood is dramatic, fast paced and inspiring. After a bowl is formed, it’s easy to want to call it done and move on to the next bowl. But not so fast, that’s where the bowl sanding tools and finish techniques come in.
If you have fellow woodturning friends, you know there are endless ways to sand and finish a wood bowl. There are the guys that treat sanding as a religion and will spend days finishing each piece as if it is museum bound. And then there are folks that barely sand at all and like the “natural” look of the wood.
The small incremental step from beautiful turned bowl to beautiful finished turned bowl with a great finished surface can seem time consuming and painstakingly elusive. It doesn’t have to be either.
What is the best way to sand a wood turned bowl? Well, like everything else, there are many ways. Let me share with you the way I’ve obtained outstanding results sanding my bowls. I believe I’ve managed to find a happy medium between efficiency and a nice quality finished smooth final surface.
Bowl Sanding Tools
We need to address the bowl sanding tools part of the bowl sanding tools and finish techniques equation before we go any further.
My bowl sanding tools consist mainly of an angled power drill, foam-padded sanding mandrels, and a variety of sanding disks. See my Recommended Sanding Equipment guide for all the details.
The electric drill I use is a variable speed that allows for more controlled sanding at high and low speeds. The angled neck of the drill helps to access bowl interiors with ease. I’m surprised how inexpensive this drill is online, here’s the listing.
Foam-padded sanding mandrels, with their velcro receiving top layer, make changing sanding disks quick and easy. The foam component on these pads cushions the sanding process and prevents the sandpaper from making harsh effects on the wood surface. The foam pads also help by making transition areas on the bowl blend smoothly.
My Sandpaper Back Story
Frugal parents raised me, and until adulthood, I thought all sandpaper grits were really the same. The reason for this was growing up I never saw new sandpaper purchased ever, as far as I knew. So the “sandpaper” scraps, essentially paper with little to almost no abrasive left, must be okay I thought. Nothing can be further from the truth.
Sandpaper is the critical component of my bowl sanding tools. And sandpaper needs to be treated like any other tool in this process. In fact, some turners refer to coarser grits as their “60 or 80 grit gouge.” Ha. I think you get what I mean.
But, seriously, sandpaper needs to work or “cut;” otherwise, it is not helping this process. Just like a dull gouge that burnishes more than cuts, worn sandpaper is useless and wastes time. After sandpaper stops cutting it needs to be pitched and replaced.
Maybe that’s why I hated to sand. Go Figure!
Not All Sandpaper Is The Same
I’ve graduated beyond my parents’ eternal, pinch-a-penny sandpaper-lasts-forever thinking, but I still like to save money, too. So in order to blend my money-savings roots with a quality sanding process, I purchase two different types of sandpaper.
The cost-effective sandpaper I use is the Hurricane Blue disks, and the higher quality disks I use are the Mirka brand. I’ll explain how I use these two different disks in my sanding process in a moment. Here are all available grits for each brand along with Amazon links to check the current price and availability.
|Two-Inch Sandpaper Disks||Three-Inch Sandpaper Disks|
|80 Grit||80 Grit|
|120 Grit||120 Grit|
|180 Grit||180 Grit|
|220 Grit||220 Grit|
|320 Grit||320 Grit|
|400 Grit||400 Grit|
|600 Grit||600 Grit|
|Three-Inch Mesh Sanding Disks|
The Hurricane Blue sanding disks are simple, straightforward sandpaper with a velcro attaching back. These are the super cost-efficient sanding disks which do a good job sanding, and I don’t mind using them liberally.
Mirka brand sanding disks are commonly used in the automotive bodywork industry as well as woodworking. These higher-quality pads are made of mesh fabric and cut wood beautifully. Because they are made of mesh, they can be pulled off the velcro pad and instantly become free of any dust or build up. The Mirka brand sanding disks perform very well and last much longer. The mesh pads also sand fantastically on wet green wood.
Discovering that sandpaper needs to flow with the grain was one of those ah-ha moments while learning woodworking that sticks with me. I still marvel at this simple wood-grain property. Break the rule, and the scratch marks will show.
If the sandpaper cuts against the grain of the wood, marks from the sandpaper will be visible. However, turning the sanding direction 90 degrees makes the paper move in the same direction of the wood grain, and everything looks great.
When I started turning bowls, it took me awhile to learn to determine which direction to make supported cuts with the bowl gouge. But what about bowl sanding directions compared to grain direction?
I like to turn side-grain bowls. If you look down on a side-grain turned wood bowl, there are two locations that are end grain and two positions 90 degrees away that are both side grain.
How do you sand the bowl “with the grain” if the grain is in all different locations? Flat boards are easy; bowls are very different.
The sanding purist has already clicked off this page by now, most likely when they read “electric drill.”
One theory for sanding, the purist theory, is sand by hand. Everything! Take the time and manually work through all the grits and create a beautiful final finish. Yes, that is possible, but hold on, there are other ways.
My childhood experiences attempting to accomplish anything with abrasive-free sandpaper perhaps taints my view on hand sanding. Actually, I’m not sure I have an opinion…it’s more like a reaction. “Oh, heck no!”
I have zero desire to turn a beautiful wood bowl then spend the rest of the day, or several more days, hand sanding. I’m already looking longingly at another chunk of wood to put on the lathe in a few moments.
Brute Force Sanding
On the other end of the spectrum are turners that drop the gouge and grab the power sander all without turning off the lathe. They push through the grits like shifting gears in a high-speed race to the finish.
While this approach, at least the speed part, appeals a bit more to me, the results are somewhat lacking. Also, if there are tool marks or blemishes, this aggressive bowl sanding technique won’t fix those problems.
Recall that grain direction discussion above. When all sanding is done with the lathe turning, the sander is cutting against the grain half the time. Against the grain, sanding leaves scratch marks no matter what the final sanding grit.
My Sanding Technique Process
An attempt to blend speed with quality is my approach to using my bowl sanding tools to obtain the best results for me. I’m not looking to make my finished bowls museum quality, but I also don’t want visible scratch marks, either.
Don’t worry; I’m not going to suggest any hand sanding. Rarely will I hand sand a bowl. I still want to get the sanding over with as soon as possible and get to the next bowl blank.
Examine the bowl surface for any trouble areas: tool marks, gouges, or a nub or divot in the center bottom. If the center bottom does have a nub or divot, use specific bowl bottom techniques to fix the area before you start sanding.
Depending on the extent of any trouble areas, start with a coarse sanding disk, perhaps 80 grit. With the lathe off, sand with the grain (more about this in a minute) just in these trouble areas. With the trouble areas fixed, move up to a finer grit sanding disk.
Turn the lathe at a slower speed, around 300 rpm, begin sanding the entire bowl surface. Sand from rim to center and after a short time, stop the lathe and address the areas where the rotating sanding cut against the grain. The locations to inspect are usually the end grain and transition areas between the side and end grain.
After finding the newly created scratch marks in the end grain areas, with the lathe off, sand with the grain to remove these marks.
I then move up to the next finest grit sandpaper, once the surface looks smooth and free of scratches. With the new sandpaper attached, I will return to step three and repeat the steps three, four and five.
Finesse The Trouble Spots
Once you become aware of these trouble areas, you will instinctively know where to find them. Potentially, anywhere the sanding disk cuts across the wood grain will produce scratch marks.
Surprisingly if you run across an area that is problematic, it’s very common to rotate the bowl 180° and find the same issue on the other side of the bowl.
Take a look at the graphic below. While the bowl was spinning, the side grain areas were in line with the side of the sanding disk. So, they were cut “with the grain.” However, the end-grain areas and the transitional areas in between were sanded at least partially “against the grain.”
The red and yellow marked areas are what needs addressing with the lathe off. These trouble spots just need a little more attention before moving on to the next sanding grit.
Power Sanding With The Grain
The idea of power sanding with a spinning disk with-the-grain might seem odd at first. However, turning with the grain is very achievable. It does take a bit of practice.
At no point should the entire circular sanding disk engage the wood bowl surface. If it does, the sanding pad grips the wood and vibrates wildly to free itself. Instead, the best sanding action is on the side of the sanding disk.
I’m right handed and hold the electric drill in my right hand. Turning my wrist slightly angles the sanding pad and utilizes the right edge of the pad only.
Using this right side of the pad, which turns in one direction, we can sand with-the-grain. Simply think of the right side of the sanding pad as being linear and line it up with the grain as you sand.
Keep the pad moving without stopping in one area. A long pause can remove too much material and leave a mark. Also, let the sanding disk do the work. You should not be pressing hard on the disk. If you find yourself pressing to make the disk sand, it might be time to replace the sanding disk.
Turning and twisting your wrist will position the sanding pad side in various locations to better line up with any wood grain flow. In step four described above, I typically work from the outer rim around the bowl several times sanding the grain until I reach the center. The active lathe sanding only takes a minute or so.
The better your turning skills get, the less sanding you will do. I used to start at 80 and go to 120, 180, 220, and then 320. Now, most of the time I only sand 180, 220 and 320 grit. Three grits reduce the sanding time even further.
Don’t Cross the Center
With the lathe spinning, like in step three, do not cross the center line during power sanding. Stopping at the center may seem strange at first, but crossing the center line equals double sanding.
The area sanded right before reaching the center point is the same area on the other side of the center point. If you cross the center and sand on the other side, a trough or shallow valley will begin to form around the bowl bottom center.
Sandpaper Grit Progression
The purpose of progressing through various sanding grits is to remove the scratches and marks from the previous sandpaper grit.
The sandpaper grits need to progress in a way that is most efficient time-wise but also does the job of removing the previous marks.
When I sand, I use the “fifty-percent up” guideline. Each sandpaper grit is fifty-percent finer than the previous grit. An example of this progression is 80, 120, 180, 220 (or 240 depending on manufacturer), 320, 400, 600 and so on.
If you have mastered removing tool mark tricks, then you don’t need to start with a coarse grit. Depending on how smooth your surface is, you may begin at 120 or 180.
I usually start at 120 and proceed up to 320. That process is only four changes of the sanding pad and does not take much time. If you’re starting out, you may need to spend more time with 80 grit smoothing off tool marks before moving up through the process.
320 grit is my stopping point because my favorite food safe wood bowl finish, and other oil-based finishes need to be able to soak into the wood pores. Sanding smoother than 320 closes the wood cell pores and makes it difficult for the oil finish to penetrate.
Green Wood Sanding
Yes, you can sand green wood. High-quality sanding pads work best. If a wood is sopping wet, I will let it turn on the lathe at a slow speed for ten or fifteen minutes. Pausing a bit after turning the surface usually allows enough evaporation to make sanding much more manageable.
Here’s another reason why I have two different types of sanding pads in my bowl sanding tools arsenal. Green wood can be nasty to sandpaper. The wet fibers combined with the tree resins can quickly gum up regular sandpaper rendering it useless.
The downside with the Hurricane sandpaper pads is they don’t last long on wet green wood. They will cut green wood, just not as long as the Mirka brand sanding pads.
Mirka sanding pads, made of a mesh material, are easy to clean off, usually just pulling them off the velcro foam pad is enough. A quick shack off and they go back on ready to continue.
The downside of the Mirka pads is that mesh material will grab the irregular surface of a natural edge bowl and tear. The Hurricane Blue sanding pads being a flat and even paper material do not grab rough edges often and do fine on drier woods.
So there are several trade-offs between performance and expense when it comes to sanding disks. For me, I find blending the features of two different types of pads works best.
These are the wood bowl sanding tools and finishing techniques I use in my bowl making process. And here is my Recommended Sanding Equipment.
Your process might be different, and that’s perfectly fine. Please leave a comment below and let me know how you sand and what bowl sanding tools you use when finishing your bowls.