The Best Sanding Sticks and Files

The grit progression is the whole technique

Here is the mistake that produces a visible nub mark under paint: sanding the nub away with one medium grit, declaring it gone, and priming. The nub is gone. The scratch pattern the abrasive left is not, and primer plus a coat of paint makes it more visible rather than less, because paint pools in the scratches.

A working progression, on bare plastic:

1. 400 to 600. Remove the material. This is the only step that changes the shape of the part.
2. 800 to 1000. Remove the 400-grit scratches.
3. 1500 to 2000. Remove the 800-grit scratches. On a matte-finished kit, stop here.
4. 3000 and up. Only if the part is gloss or clear, where you are polishing rather than sanding.

Each step exists to erase the previous step. Skip one and you are sanding scratches into a finer scratch pattern that still reads as a scuff under paint.

Why the thickness of the stick matters

A thin, soft foam stick conforms to whatever it touches. On a curve that is exactly what you want. On a flat panel it is a problem: the foam wraps over the panel’s edges and rounds them off, and a Gundam shin with softened edges looks melted.

That is why GodHand sells the Kamiyasu in a 3 mm and a 10 mm version with a harder sponge in the thick one. The 10 mm block stays flat, so flat stays flat. Use the thin one on curves and the thick one on panels, and the difference is visible on a bare part before any paint goes on.

Sand wet, almost always

Dip the stick in water first. Three things happen: the abrasive stops clogging with plastic swarf, the cut becomes finer and more even at the same grit, and you stop breathing plastic dust. The grit numbers on a GodHand stick are printed in water-resistant ink specifically so wet sanding does not erase the labels.

The exception is coarse shaping on a part you will prime heavily anyway, where dry sanding is faster. Everything in the 800-and-up range is better wet.

When you need a file instead

A stick cannot enter an internal corner, and it cannot cut through a heavy seam line quickly. A needle file does both. The triangular and knife profiles in a cheap six-piece set reach into corners that no abrasive sheet will ever touch.

Files leave coarse scratches, so a file is always step one of two — file, then work up through the sanding progression. And files are far too aggressive for pre-colored snap-fit parts: one firm pass goes through the color layer, and now the part needs painting.

The pre-colored plastic trap

Modern Gunpla is molded in its final colors. Sanding a nub on a pre-colored part removes the shiny, as-molded surface and leaves a dull patch of the same color — which is often more visible than the nub was.

Two honest answers. Either sand lightly with a fine grit only, accepting a faint mark, or accept that cleaning nubs properly means painting the part afterwards. A matte topcoat over the whole kit also evens the sheen out, which hides the dull patch without a full repaint. The cut-and-pare sequence that minimizes how much sanding you need at all is in how to remove nub marks.