What is the best way to fix gaps in mitered joints for a wooden keepsake box?

[Anthony.W]

I’ve been trying to make a simple wooden keepsake box with mitered corners, but I can’t get them to close up tight without a tiny gap on one side. My clamps and corner tape just aren’t doing the trick, and I’m wondering if my saw blade or my technique is the real issue here.

[Abigail_H]

I chased the fit on a keepsake box for weeks. With any mitered corner, I’ve learned the tightest joints only show when the pieces are dead flat and the glue is allowed to grab without movement. If the blade drifted even a hair or the stock isn’t perfectly flat, you’ll end up with that tiny gap that won’t close when you clamp. It’s not always the math of the angle; it’s the real world quirks of wood and glue.

[Chloe_H]

I did swap blades and tried cranking the clamps harder, but the gap persisted on one side. The glue-up felt fine elsewhere, but that side kept pulling away. Maybe the stock is a little cupped or the end grain soaks glue differently, or the corner tape isn’t the right fix to hold things until the glue cures.

[AnthonyRH]

Do you think the stock itself is warped?

[BenjaminJR]

I once wandered into finishing tricks and ended up chasing the flush look more than the joint. Sanded and waxed, then tried a tiny bevel on the inside of the joint, and the line looked better for a moment, but the issue came back as soon as I clamped tight again. It felt like a nudge in the wrong direction and I stopped short of committing to a fix, unsure if I’d just trained myself to chase the wrong symptom.