Oh, carbon steel putty knives come in all sorts of sizes-from tiny 1-inch ones to big 6-inch (or even bigger!) ones. Let's break 'em down so you know which to pick.
First, the small ones: 1-inch to 2-inch. These are perfect for tiny jobs-like filling nail holes, touching up small cracks in drywall, or spreading putty in tight spots (like around door hinges). I keep a 1-inch one in my toolbox for those little fixes-last week, I used it to fill nail holes in my picture frame, and it was way easier than using a bigger knife. No over-spreading putty, no mess.
Next, medium sizes: 3-inch to 4-inch. These are your workhorses. Great for spreading putty on bigger cracks, patching small drywall holes (like the size of a fist), or scraping paint off walls. I use my 3-inch one most often-did my whole bathroom drywall repair with it. It's big enough to cover area, but small enough to maneuver.
Then the big ones: 5-inch to 6-inch (or more). These are for large jobs-like spreading joint compound on drywall seams, scraping paint off big walls, or removing wallpaper glue from large surfaces. I used a 6-inch one when I redid my living room walls-saved so much time 'cause it covered more area per swipe. But don't use a big one for small jobs-you'll end up with putty everywhere.
How to choose? Think about your project. If it's tiny (nail holes, small cracks) → 1-2 inch. If it's medium (small patches, regular scraping) → 3-4 inch. If it's big (drywall seams, large walls) → 5-6 inch. I actually have three sizes-covers every job. No need to buy every size at first, but start with a 3-inch-it's the most versatile. Trust me, you'll use it more than you think.
