Welcome back to another episode of No BS Woodworking where we give you actionable information you can actually take into the shop today and use. There's no fluff, no sponsors, and of course no BS. Today we're going to talk about sanding.
Sanding seems real straightforward right and especially I know a lot of us when we got started we thought it was. We've spent all this time learning and building a project only to you know we can make it look kind of funky at the end when you're just finishing up. Divots, rounded edges, slight tapers of wood.
The flaws can be endless when you're sanding if you don't. do it correctly so today i'm going to show you all the tricks and tips you need to know to sand perfectly and get ready for a smooth amazing finish now small disclaimer most of the things i'm going to show you today we do carry on our website and that's because this channel is supported entirely by people like you visiting km tools and we really appreciate it. And that's how we can do no sponsors, and it's how we can give unbiased reviews and information.
And the reason is, everything in our store is things I believe in and use in my shop on a daily basis. So, come on into the bench, let's talk about which type of sander you should pick. These are the three basic types of sanders that you'll see in most shops.
The random orbital sander is first and foremost everybody's favorite, and the one I use 99% of the time. The reason is because it spins while also oscillating, and that allows you to create a random scratch pattern. so that it's not visible or noticeable when you are moving through the grits and putting finish on. A belt sander like this one is for incredibly fast stock removal.
The only time I'll use this if I need to remove finish or paint, or for some reason need to take out a bunch of stock in maybe an already assembled project because I made a mistake, something I can't take apart and put through a planer. This is a pad sander that uses these square sheets of paper. Usually they come in quarter or half sheets and it just vibrates, no spinning. These are much, much less aggressive than than these two and they're great because they can get into corners and things like that. But if you're just going to buy one sander, get a random orbital.
These are not necessary for your everyday woodworker. Let's go take a look at a couple other machines I have just for the sake of showing you what they are. We won't spend too much time on them so we can round out kind of all the sanders we have here in the shop.
These are oscillating spindle sanders. This one also comes with an oscillating belt. They're for sanding edges and curves. And this is a drum sander. I don't know if you can see behind me in the background, that is a 54. 47 inch wide belt sander, which we just got.
Don't need to talk about that. That's a production machine. Belt sanders are great. Things to know if you're a woodworker, everybody wants one of these because they think it's gonna make sanding easier.
It does not. It does make sanding very square and flat and it's fantastic for that. But because it does not oscillate and spins it in a line, you do need to come back and random orbit sand things.
So usually I'll stand up to 220 to get something nice, flat and square, especially things that are very thin or too short for the planer. and then I'll take it back to random orbital and bump down a few grits and sand it again. So a couple of other sanding machines that I own.
You don't need to know too much about them. They are great machines, but not super important for day-to-day sanding. Let's head back over the bench and talk about a few hand pads.
There's hand sanding pads, which can be anything you can put sandpaper on. Super 77 spray on a block of wood creates a good, firm sanding pad. We carry these ergonomic ones that I love because it takes a 5-inch hook-and-loop disc, and it has an edge that you can get into corners with. that's just a tiny bit tapered away from square so that you don't, you know, if you wanna tilt up and not sand one edge or the other, it's great.
There's also PSA-backed sandpaper. You can get sticky sandpaper, but hand sanding is a part of finishing. Obviously, a random orbital can't get in everywhere, which is why we should talk about when you should sand. Okay, let's talk about when you should sand. Well, Jupiter needs to be in retrograde.
It needs to be between 32 and 56 degrees Celsius. No, I'm just kidding. What I mean is when you should sand.
What should you sand before? before assembly or after? Well, a lot of times, like this is some great example. These are sample pieces I was making with our new box joint jig.
And you can see, I didn't sand the inside because of course they're just sample pieces, but it would be very hard to get in here, especially if you wanted to quickly sand with a random orbital. Really these corners you could only do by hand. So you wanna sand before assembly. However, one thing you need to be careful of is the joints, right?
Obviously, if you sand the inside of joints, you can cause gaps to appear. So you want to stay away from them. An easy way to do that is just put some, you know, blue tape on the joint to protect the areas you don't want to sand. Anything that will be inside of a joint and covered with glue, you don't need to or want to sand because, like I said, you can create gaps. So stay away from those areas, but you do want to sand your parts a lot of times before you assemble.
Sometimes I'll just do them up to like 120 or 150, but get them nice and sanded so that way I can come back in with a hand sander at the end. You want to make sure you get all the areas that anybody might touch, even if it's not going to be seen. Next is...
is use good sandpaper. Now I have done, which is hands down the best sandpaper test of all time. I used robots to test 19 different brands and unequivocally it was the Cubitron extract and it comes in a net and a... film, the net removes material much faster, the film is a lot stronger.
So it's kind of a trade off between the two. But the cost difference is not the price per disc, it is the price per grams removed, you can go watch that video if you want to see kind of more in depth what I'm talking about. But it is the time value of money and good sandpaper makes all the difference. Like, do you want to be standing for a week or you know, a couple hours, it really is that big of a difference.
So highly, highly, highly recommend the sandpaper. go watch that test if you want to see but head over to cam tools we got these for you and that's enough of the basics let's get into how to say it good dust collection is the single biggest quality of life improvement in the shop and sanding is by far one of the biggest times that you do need good dust collection i bought this sander this was the first nice sander i bought and my god was it a big improvement you can buy it cheap i think this is like petri woodworking he's universal adapters and a hose clamp. It'll fit on any sander. You can hook it up to a cheap sander like this one, which these go on sale at Home Depot for 50 bucks, like five times a year.
Or this Bosch, it's kind of medium price, several hundred dollars, or you get, you know, the real expensive ones that come with like the Festool or the 3. 3M sander, but highly recommend good dust collection, not only for your lungs and for your health, but because as you're sanding, dust buildup is going to cause heat, which heat is the enemy of sharpness, which is going to ruin your sandpaper. So it actually helps in the end result as well. Now let's talk about how to sand properly.
All right, there are two things in sanding that are absolutely critical that you know and do correctly to get a good result. This is the first one, that is sanding through the grits. Now, if you're using a film finish, you could sand all the way up to 180 or 220. because it's gonna stay on top of the wood and build a film finish.
If you're doing a hard wax oil like Rubio Monaco, you would just sand to 150, which is the manufacturer recommendation. Now, I'll briefly get into the science of sandpaper so you understand why. Good sandpaper, aluminum oxide, and ceramic, that's what the extract in Cubitron is, it's a ceramic-based cutting medium. They have what's called friability.
The better the friability, the longer lasting the sandpaper is, and that's what it refers to, the fracturing of the grit into a new sharp surface. So, this was your cutting medium, as you begin to cut, it's gonna fracture down to something like this. This is gonna fall off and it's gonna continue to cut.
Anybody who's used extract or Cubitron knows when you get started, you start to feel that little grit on there in the beginning, and that's because it has really good friability. fractures off creates a new sharp cutting surface. Now, working through the grits, why is this important?
Well, 80 cuts deep. This is obviously not to scale for all you engineers out there, but 80 is going to cut really deep and really fast. 220, a little less deep. a little slower and so on. So if you were to go 80 and sand your whole project and then skip up to 220, not only is it going to take forever to get to the bottom of these valleys here that the 80 left behind, but probably you're going to leave swirl marks that aren't going to show up until you put finish on the material.
So you want to work through your grits 80, 120, 150, 180, 220, obviously stopping where the manufacturer for your finish recommends, but that is one of the two most important things. The next one is to sand. flat surface.
Let me show you how to do that. Now this is called the pencil trick. It's really important and I think a lot of content creators describe this incorrectly and let me show you why. So you want to take a pencil. Now you don't want to use a tiny mechanical pencil because if you have very porous wood you may get very deep into the grain and you may not actually ever even get to that pencil or it may trick you into thinking you haven't sanded somewhere.
So you want to use like a nice number two or a carpenter's pencil and you're gonna just draw lines across the entire surface of your board. And I left a little Easter egg in here to give you to show you why I think people kind of explain it Incorrectly because there is a way to do this wrong So what you want to do is work through your grit starting with 80 moving up until your pencil is gone with a catch Let me show you All right, you can see I sanded the whole thing, but there's still a little pencil left in the center. That's because I purposely put a little hollow in here with my sander before we started shooting.
And that's to show you that you don't just need to get rid of all the pencil. You need to sort of use your brain a little bit. And if you pass over an area where all the pencil is, the pencil around it is gone and you know that you've gone over it and there's still some left it doesn't mean you need to turn your sander and get that area or just sand this area because then you're going to get a hollow over the whole piece what you want to do is then keep on the same grit and redo your pencil until you get down there and you want to be moving at about an inch per second so one one thousand two one thousand three one thousand four one thousand five one thousand until your pencil is gone and if you see areas where it is just not going but it has removed around that and you know you went over it you do want to just stop redo your pencil and keep going then once you get a nice clean flat surface you would go up your grit by the way i saw my piece was slipping all over the place i put these pads down these things are freaking awesome also carry these over at KM Tools.
Worked great for routing too. Real quickly before we move on, I just want to show you why it's so important to do the pencil trick, but also keep in mind that you're doing it flatly, is this is a sample joint from our new box joint jig one of our employees did, and I set him up to sand it, and I walked away. I told him about the pencil trick and sort of overlapping, and he just wanted to get the pencil down, and he started trying to get the box joints that were proud to match up with the ones that were not, like my parents, and he just kept sanding. You can see there's like a real... gradual curve to this and that's like a classic beginner mistake that's really easy to fix if you just are really careful about just removing the pencil and that's it and not trying to like solve problems while you're in that one pass.
Just redo your pencil, keep going, do it evenly. Now as you're working through the grits you want to clean between grits. You can do that with a little broom like this or just a blower.
You want to just make sure you're getting rid of things like contaminants, you know, maybe like a piece of the sandpaper or a piece of dirt got on there that you might mash in and scratch your part when you move up to the next grit. So just make sure you clean it off. And then when you finish, there's something you may have heard of called the water popping.
Let me show you what that is. Now, water popping is something that not everybody agrees on, but basically you take water, you rub it on your surface, and it causes any grain that would pop up when you put finish to sort of stand on end, and then you can come back and finish it. The things that...
People do agree on though is that it does happen, but with oil-based finishes, it's not water-based, so sometimes it's not as bad. I personally don't do it. I like to put my finish on first, and I do one coat, and then I give it a nice thorough sanding with a very high grit sandpaper, like 240 to 320. Or here is one of the coolest things ever, which is something we carry over at Cam Tools, but it is hook and loop scotch brite pads. This is equivalent to, you know, something like 300 to 500 grit sandpaper and it's fantastic for between coats. Sandpaper can sometimes remove too much.
This is something I figured out when we started carrying Rubio. They recommended those Scotch-Brite pads which they sell like this and I was like oh my god that takes forever and anybody who knows me knows I like efficiency and speed most of the time. pick up one of these it is fantastic and it just leaves a surface that is free from any of those little nibs that are created by finish or water popping whatever it is it is really really cool for between coats highly recommend these especially if you're doing hard wax oils the next thing you need to know is how hard should you be pressing well this is a random orbital sander and it does its best work when it is spinning and moving randomly and if you press too hard it's going to stop spinning it's still going to vibrate but You don't want to be pressing so hard that it stops.
Let me show you. I'm going to start with it spinning and I'm going to press too hard. I'm going to let off and you'll be able to see the difference.
I think people think that if they press really hard, it'll remove material, but it's the exact opposite. It's just like sawing with a handsaw. You want the saw to do the work, not your arm.
So when you're sanding, let off of it just nice. The weight of your hand is all you need. You want that random orbital to be spinning and it's going to do its job just right.
Now let's talk about edge sanding. Lastly, I forgot one thing before we get into edge sanding. Let's talk about right before you get to finish. You want to know if you did a good job. Finish will show you all your mistakes.
It'll show you if you skipped grits, it'll show you if you sanded too much, but it's really really hard to see before you get there. So a good raking light will really help you check out your project. It can be a flashlight, you can hold it square with your project, and you can kind of see but A big light like this can be really, really helpful. If you just set it to the right height, you can take a look down the board and the shadows will kind of show you the imperfections. I don't know if you can see right here, but on these box joints, there's some areas that have not been sanded yet.
This is of course the piece that one of my employees messed up, but it's a really great example of errors that you can find with a light that are a lot harder to see before you put on finish. Edge sanding can be a serious drag because You know, you've already spent three, four hours sanding an entire project with a random orbital, and now you have to do the edges. And it is really tough to do the edges with a random orbital, but I will show you a trick here in a second. So a few ways to make this a little bit easier on yourself if you are hand sanding.
These sanding pads are great, but you really want to count your strokes. when you're hand sanding an edge because it is again like the pencil trick it is really easy to do too much so you know i like to count i go one two three four five six and then same thing one two three four five six and you see how i'm like rotating from 90 degrees boom boom boom boom over and over the other way to do it is just grabbing a piece of sandpaper now who's ever done this like see how my hand is slipping back and forth take these and just fold them on themselves like this. And then the grit of the sandpaper will stick to your hand.
It's much easier. Again, count your strokes for each part because you wanna make sure that all your edges match from one leg to another, or the top on the left, the top on the right. So you just, same thing, wrap your hand around, one, two, three, you know, and so on. You can use a hard block like this, but again, it creates like really sharp edges.
I would definitely use something soft, which is Where I found this cool thing which we now carry, let me show you. This is a foam pad. It turns your flat random orbital into something that can do a curve and you can actually stack them up really tall if you have like a huge inch and a half round over on the edge of like a modern kind of 90s style table.
You use one of these but let me show you how this works. Just take this big foam pad, put it on here. This is also great if you're trying to buff something.
This works great with a buffer. You want to make sure if you have a speed setting on your random orbital that you turn it down because edges can go real fast. Take some sandpaper and now watch how easily this sands the edge.
Look how good that came out. I sanded it to about right here pretty diligently. That came out so so so clean. So these foam pads are really really cool. The other option is if you have a bunch of pieces that are really narrow is you stack them in your vise together.
And that can give you a nice flat surface, especially if you're just trying to get a square edge with a really tiny chamfer like this. You can put them in your vise, make sure they're all the same height, and then sand them evenly that way. Let's talk about protecting sanded surfaces as you finish up assembling your project.
I made this video where I did these maple end grain cutting boards. And in that video, there's this part where I'm trimming down the edges, and there's blue tape on it like this. And that is because I had to run it through my table saw.
I'd spent so much time sanding end grain that I did not want to get any scratches because tiny, tiny little scratches that you can't see, as soon as you get finished on them, they pop just like that. So I put blue tape on it, I ran it through my table saw like this, and there's like 50, 60 questions on that video asking me why I did that. And it is really important to protect sanded surface. Blue tape is your best friend for that.
The other thing is getting some sort of pad like these just to protect it. and then making sure you clean it before you put finish on. But you wanna make sure you protect sanded edges because the tiniest little nick, scratch, whatever, can really show when you put finish on it. If you do get a little nick though, here's a little tip.
Take a wet rag, just damp, put it on your piece and use an iron and it'll pop that right up and it'll save you a lot of headache and a lot more sanding. You also want to be very careful of plywood. Plywood has very thin veneers.
You do not want to start with 80 grit. Plywood is already flat and it's pretty well sanded already. Let me show you why and how quickly you can sand through the top layer of plywood. So you can see here that was about 10 seconds of sanding with 80 grit. and we went right through that first layer.
I mean you can really see how thin that top layer is. This is the bottom layer. It's I mean it's even thinner than the other layers.
So you want to be really careful when you're sanding plywood. I would start with 150 or 180 and just work up the grits to 220 and leave it at that because you don't want to ruin a great project by getting through the top layer of veneer. There's some people who think if you sand end grain to a higher grit that it's going to take finish similarly to the long grain.
I don't know. I don't know how true that is or if it matters. I personally think that the end grain looks super cool when it's a different color.
It looks very 3D like these box joints. So some people say that it's probably true cause you burnish the edges. So it won't absorb the grain as much the end grain and can absorb quite a bit more material than the long grain. So you can burnish the edges if that's something you're worried about but not something that I would spend too much time worrying about.
Let's back it on up here and wrap this thing up. Now I certainly can't make sanding fun, but. I hope with some of these tips you can work smarter, not harder. And the biggest one, God, I urge you, go watch that sanding test if you don't believe me, but get high quality sandpaper, even if it's not the one from my website. That is the biggest game changer.
It is your time and your enjoyment is greatly affected by how long you do something where your hand is buzzing and there's loud noise and you're absorbing sawdust into your brain hole. It's just not fun. So, Upgrade your sandpaper, follow some of these tricks. I hope this helped you and I hope you really like this No BS series.
I really like doing it. Supported entirely by people heading over to KM Tools. So I thank you for your support. As always, stay safe in the shop.
Have a wonderful day.