I thought I had this sandpaper thing figured out. Turns out I don’t. Sandpaper grit is a science in and of itself. Is it complicated? No. But considering what happened when I sanded the clapboard (and in between paint coats), I’ve decided I wasn’t the problem as much as the sandpaper was!
Looking back, I was using the wrong sandpaper the whole time. I was using fine grit sandpaper, not medium. While fine-grit sandpaper would have been OK after the second coat of paint, I should have used medium-grit sandpaper during the first sanding.
Another newbie mistake and lesson learned!
Sandpaper Explained
I don’t know why it’s called “sandpaper” when it has nothing to do with sand (to my knowledge). Sandpaper consists of two things: abrasive particles and backing.
Sandpaper backing can be paper, sponge, or even cloth — basically, something that won’t hurt your hands.
Sandpaper particles are natural or synthetic. They’re sifted and sorted by size, then bonded to the backing. Sandpaper particles can include:
- Flint: a natural and durable grain that’s fairly coarse.
- Emery: a natural particle that removes corrosion and polishes metals (also, good for fingernails!).
- Garnet: not the gemstone. It’s a natural material that’s softer than flint and emery. It tends to dull quickly.
- Zirconia alumina: synthetic (in case the “zirconia” part didn’t give it away), it’s long-lasting and coarse. The particles sharpen as you sand.
- Aluminum oxide: also durable and synthetic, it’s great for sanding hardwood.
- Silicon carbide: durable beyond belief and perfect for all your sanding needs.
While some manufacturers list the particles in their sandpapers, others call it “proprietary mineral technology.” So, instead of looking for a specific type of particle, it’s better to rely on sandpaper grit as a guide to picking the right sandpaper for your project.
Sandpaper Grit Guide: What Those Numbers Mean
When you head to the store to buy sandpaper, you’ll notice that the package usually has a name and a word on it. The number could be 50, 220, or almost any number. That number is the grit.
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But if you’re not a numbers person (raises hand), you can rely on the words. Fine, coarse, medium — they tell you what kind of grit you’re looking at. Found some random sandpaper lying around and think it’s right for your project but can’t tell by looking at it? The grit number and grit name are usually on the back of the sandpaper sheet.
While there are lots of sandpaper grit ranges, there are particular sandpaper grits that you’re more likely to use when working on your dollhouse projects.
Coarse: 60 to 80 Grit
Sandpaper in the 60 to 80 grit range is coarse, meaning it has sharp materials. Coarse sandpaper grits are for sanding off things you don’t want (like paint drips). While you can use coarse sandpaper for shaping and rounding edges, you shouldn’t use it for fine detail work or edges you want to keep in shape.
Medium: 100 to 150 Grit
In the next range, 100 to 150, you’ll find medium sandpaper grit, the most commonly used type. Medium-grit sandpaper is best for unpainted surfaces. If you’re prepping unfinished wood for painting and sanding is part of your prep, a 150-grit sandpaper is your best bet.
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A medium grit smooths the wood surface just enough, so you don’t get “wood fuzzies” but leaves enough “grip” in the surface so the paint sticks. The more pressure you apply when using medium grit sandpaper, the more you’ll sand off.
Fine: 80 to 220 Grit
And then there’s fine-grit sandpaper. This falls in the 80 to 200 range, and it’s what you want to use when you sand between paint coats. Fine sandpaper grit is just coarse enough to sand off wood fuzzies and paint mishaps, without removing the paint you just applied. You generally won’t use fine-grit sandpaper on a first sanding (like prep work). And you shouldn’t use a fine grit sandpaper on unfinished wood you plan to paint. It just won’t work.
Ultra-fine: 220 and Over
If you thought fine-grit sandpaper couldn’t get any finer, think again! There’s also ultra-fine grit sandpaper!
It’s doubtful you’ll use an ultra-fine grit on your project, but you can use it on painted surfaces that need a final sanding, thanks to the light and delicate nature of this grit. Ultra-fine sandpaper is usually used for wet sanding, though.
Extra Coarse: 24 to 36 Grit
Super-tough, super-strong, and super-coarse. This is what you use on old paint, varnish, and other finishes you never think are coming off. Only use this grit on finishes that will not budge.
Super-fine: 600 Grit
I know there’s a pun in here somewhere about looks. This is as fine as sandpaper comes and you should only use this grit for polishing jobs.
Sandpaper Grit Scale Differences
Of course, some things in life aren’t simple, and sandpaper is no exception.
The sandpaper grit ranges listed above are those used in the United States. Before it merged with the Unified Abrasive Manufacturers’ Association, the Coated Abrasives Manufacturers’ Institute (CAMI) created the above scale.
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The CAMI scale measures the size of sandpaper grit particles in microns. (Before you ask, “How big is a micron?” the answer is “small.” Specifically, the word micron is an abbreviated term for “micrometer.” Now you’re wondering, “How big is a micrometer?” The answer is “one-millionth of a meter. And thus ends our math lesson for the day.)
Without getting into all the details, the higher the grit number, the finer the particles. And the lower the number, the larger the particles and the coarser the sandpaper.
Most of the time, the sandpaper you buy at the local store has a grit on the CAMI scale. However, sometimes (particularly if you purchase your sandpaper online), you’ll come across sandpaper grit that is sized according to the Federation of European Producers of Abrasives (FEPA).
If you aren’t sure what scale your sandpaper grit is on, FEPA sandpapers have the letter “P” before the number. So, it would look like P-100 or P-82.
That said, the number does not correlate directly to the CAMI scale. You have to convert from CAMI to FEPA.
- CAMI 40 grit sandpaper is FEPA P-36 or P-40
- CAMI 80 grit sandpaper is FEPA P-80 or P-100
- CAMI 100 grit sandpaper is FEPA P-100 or P-120
- CAMI 120 grit sandpaper is FEPA P-120 or P-150
- CAMI 220 grit sandpaper is FEPA P-180 or P-220
- CAMI 400 grit sandpaper is FEPA P-600 or P-800
Which Sandpaper Grit Is Right for My Project?
It depends on what you’re trying to accomplish! But, you knew that. However, I will say that based on personal experience, I would rarely use coarse sandpaper on dollhouse items. The exception is if you’re cleaning up a paint drip.
Coarse sandpaper is great for shaping wood, removing layers of paint, and fixing boo-boos. In general, you aren’t shaping wood on your dollhouse. You might be, but you usually aren’t. Mostly, you’re smoothing down wood that’s pretty darn finished (at least if you use a dollhouse kit). You’re better off with a medium to fine sandpaper grit for most of your projects.
That doesn’t mean you’ll never use coarse sandpaper on a dollhouse. If you’re refinishing a dollhouse, you’ll probably need coarse sandpaper to remove old paints and finishes and smooth things out. But for the most part, stick with the medium to fine-grit sandpaper.
Keep in mind that choosing a sandpaper grit isn’t a one-and-done deal. More often than not, you’ll start with a coarse to medium-grit sandpaper and work your way up to a fine-grit sandpaper as you paint and stain your wood.
The Nitty Gritty from Big to Small
I’m not going to lie. I really wish I had researched sandpaper grit before I painted the Keeper’s House. I had no idea there was such a difference in sandpapers. Of course (no pun intended there), I knew some were coarser than others, but I did not realize that coarseness makes such a big difference in any project.
Well, there’s nothing I can do about it now. You, on the other hand, can learn from my newbie mistakes. To stop you from messing up like I did, I created a cheat sheet for you.
Frequently Asked Questions About Sandpaper Grit
Fine sandpaper is in the 80 to 220 range. There’s also super-fine grit sandpaper (600) and super-fine grit sandpaper (600).
Coarse sandpaper is in the 60 to 80 range, but there’s also extra-coarse sandpaper, which is between 24 and 36. Be cautious using coarse and extra-coarse sandpaper, though. It can reshape the wood you’re working on and will probably take paint off.
You’ll probably use a mix of sandpapers. Start with a medium sandpaper grit for initial sanding (like priming wood), then work your way up to finer sandpaper grits as you sand between paint coats.
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