Hey, Posse! It’s Alex. And today I need to talk about something that has been driving me ABSOLUTELY crazy every time I watch a DIY finishing tutorial on YouTube.
Almost every single one of them tells you the same thing: “Sand between every coat.” Light grit, light pressure, wipe it down, repeat. Sounds logical, right? It’s repeated so often it’s basically gospel in the DIY world. But here’s the uncomfortable truth — following that advice blindly is RUINING your finishes. I did it for two years on furniture projects before a professional refinisher finally pulled me aside and said, “Alex, stop. You’re creating half your problems yourself.”
So today I’m breaking down exactly when NOT to sand between coats — and what to do instead to get those silky, glass-smooth results you keep seeing on Pinterest but can never seem to replicate yourself.
Why “Always Sand Between Coats” Is Actually Bad Advice
The logic behind sanding between coats sounds reasonable on the surface. You sand to knock down dust nibs, smooth out brush marks, and give the next coat something to bite into. Fine. But the problem is that most DIY tutorials present this as a universal rule — applicable to every product, every finish, every situation. And it is NOT.
Sanding between coats of certain finishes. especially water-based polyurethanes and lacquers applied within their recomended recoat window, can actually BREAK the chemical bond forming between layers. You’re not helping adhesion. You’re literally destroying it. The two coats were about to fuse together at a molecular level, and you just took 220-grit sandpaper to the whole situation.
And there’s another problem nobody talks about. When you sand too aggressively between coats of a tinted finish or a stain-infused topcoat, you risk cutting through the color layer entirely. I learned this the hard way on a credenza I was refinishing back in early 2025. three coats of a gorgeous warm walnut toner, sanded between each one like every tutorial told me to, and by coat four I had blotchy pale spots across the entire top surface. Starting over cost me two full weekends.
The Recoat Window Is EVERYTHING
Here’s what pros actually think about instead of reflexively grabbing sandpaper. They think about the recoat window.
Every finishing product has one. It’s the span of time, usually printed right on the can. during which you can apply the next coat and get a true chemical bond between layers. Apply within that window, and the coats essentially become one unified film. Apply outside it, and you’re relying on mechanical adhesion only, which is weaker and more prone to peeling.
So when are you inside that window? When the previous coat is dry to the touch but NOT fully cured. Still a little soft underfoot, basically. At that stage, you do NOT need to sand. The new coat will melt right into the one below it. Sanding at this point is, at best, unnecessary. At worst, it’s sabotage.
Now, when ARE you outside the window? After the finish has fully hardened, usually 24 to 72 hours depending on the product and your shop humidity. At that point, yes, a light scuff with 320-grit is genuinely useful because you’re now relying on mechanical adhesion. But even then, “light scuff” means barely kissing the surface, not the vigorous back-and-forth most beginners default to.
When You Should Absolutely Skip the Sandpaper
Let me give you the specific situations where you should PUT DOWN the sandpaper between coats and just trust the process.
Water-based finishes applied within a 2-hour recoat window. Shellac applied over shellac within about an hour. Lacquer over lacquer within 30 minutes. Conversion varnishes within their open window, which varies by brand but is usually listed as 24 hours from first coat. In ALL of these scenarios, the chemistry is doing the bonding work for you. Your sandpaper is an intruder.
Also. and this one surprises people, you should skip sanding between coats when you’re applying a flat or matte finish. The flattening agents in these products actually perform BETTER when they’re bonded chemically rather than mechanically. Sand between coats of a dead-flat lacquer and you’ll notice the final sheen is uneven. Blotchy in some spots, flatter in others. Not a great look.
What to Do Instead of Sanding
Okay so if you’re not sanding, what ARE you doing? A few things, actually.
Tack cloth between coats is still a good idea. just to pull off any dust that settled. A dry microfiber works too. You’re not abrading anything, just cleaning. Takes about 90 seconds. Easy.
Watch your application environment. Most finish problems that people blame on adhesion are actually caused by dust contamination or humidity spikes mid-application. If your garage shop is above 75% relative humidity, your finish is going to have problems no amount of sanding between coats will fix. Get a cheap hygrometer, I picked one up on Amazon for $11 in January 2026 and it genuinely changed my finishing results more than any sanding trick ever did.
And apply THIN coats. This is the real secret. A thick coat takes longer to cure, has more time to collect dust nibs, and is more likely to sag or run. Three thin coats applied within the recoat window, zero sanding between them, will ALWAYS outperform two thick coats with sanding in between. Always.
The One Time Sanding Between Coats Is Non-Negotiable
To be fair. because I’m not saying never sand ever, there IS one scenario where between-coat sanding is absolutely essential.
When you mess up. A run, a drip, a bug that landed in your wet finish, a significant dust nib you can see from across the room. In those cases, wait for full cure, sand out the defect with 320 or 400-grit, and then reapply. You’re not sanding the whole surface; you’re spot-fixing a specific problem. That’s the appropriate use of sandpaper mid-project.
Sanding as a reflexive default? That’s just burning time and risking your finish.
The Honest Truth Most DIY Guides Won’t Tell You
The reason “sand between every coat” became so popular is simple: it FEELS productive. You’re doing something. You’re touching the project. It gives beginners a sense of control in a process that otherwise asks you to just… wait.
But professional finishers I’ve talked to. people who have sprayed lacquer and varnish for 20-plus years, almost never sand between coats on production work. They control their environment, they stay within their recoat windows, and they apply thin coats consistently. That’s it. That’s the whole system.
So next time you’re mid-project and you reach for that sanding block out of habit? Stop. Check the clock. Check the recoat window on the can. If you’re still inside it, put the sandpaper down and just apply your next coat. Your finish will thank you.
FAQ
#### Does skipping sanding between coats cause adhesion problems?
Not if you’re applying within the product’s recoat window. Chemical adhesion within that window is actually STRONGER than mechanical adhesion from sanding. The key is timing. apply too late and yes, you’ll need a light scuff.
#### What grit sandpaper should I use if I do need to sand between coats?
320-grit is the go-to for most topcoats. Some pros use 400-grit on fine furniture work. Avoid anything coarser than 220 between coats, you’ll leave scratches that show through the final finish.
#### Does this apply to latex paint on walls too?
Mostly yes. Between coats of latex interior paint applied within 4 hours, sanding is rarely needed unless you have visible texture issues or runs. A light tack cloth wipe is usually enough.
Photo by Ann H on Pexels
