Model kits: number 11, chisel or curved?

Nearly everyone builds their first few kits with one blade. A number 11 goes in the handle, and it stays there through sprue removal, mould lines, seams and detail work, because it is sharp and it is already fitted. It will get you through, and it is also the reason a lot of early builds have small gouges near the joins and a slightly furred look under primer.

The fix is not a better blade. It is a second and third blade, and knowing which part of the job each one is for.

What actually goes wrong

A plastic kit asks for several different cuts: parts off the sprue, excess plastic trimmed, mould lines scraped back, edges deburred, curved parts shaped, then fine cleanup before paint. Those are not variations on one action. Cutting and scraping want opposite things from an edge.

Use a pointed blade to scrape and it concentrates all your pressure on a single tip, so it digs in. Use a flat blade for detail and it cannot reach into the corner you are trying to clean. The damage shows up later, because primer finds every scratch and seam you left behind.

The number 11, for anything with a point

The #11 is the blade everyone recognises, and it earns its reputation on precision. The long fine point reaches into tight corners, trims small parts without touching their neighbours, cuts decals and masking film cleanly, and takes light mould lines off delicate areas where nothing wider will fit.

What it is not is a scraper. That same point is why pressure goes straight into the plastic when you hold it flat and push. If you find yourself bearing down on a number 11, you have reached the end of what it is for.

It fits the K1, which is the light-duty handle most people start with.

The chisel, for anything you are removing

A chisel blade is ground flat across the tip, so the cutting happens along an edge rather than at a point. That single difference is what makes it safe to scrape with: your pressure spreads across the whole width instead of concentrating, so it shaves material away in layers rather than digging a channel.

It is the right tool for sprue marks, mould lines, deburring, flattening a surface and smoothing panels before paint. On a large flat area it is not just safer than a number 11, it is faster, because you can take a confident stroke without worrying about where the tip is going.

The #17 Small Chisel Blade is the one to start with. Where there is more plastic to shift, the #24 Deburring Blade in a heavier handle like the K5 handles bigger sprue marks without flexing.

The curved blade, for anything that is not flat

A curve keeps the blade in contact as you draw it, so the cut rolls along the edge instead of starting and stopping. On a rounded surface that is the difference between a smooth shave and a series of small flats.

It comes into its own on terrain and scenery, resin kits, creature models and conversions: anywhere you are shaping an organic form rather than cleaning a moulded edge. It also carves foam and resin far more happily than a point.

The #10 Curved Edge Blade is the standard choice, with the #12 Mini Curved Blade for smaller work.

A workflow that works

1. Take parts off the sprue with cutters, not a knife. A blade twists the part as it cuts and stresses the plastic.
2. Trim the remaining nub and do detail work with the number 11.
3. Change to the chisel for mould lines, seams and deburring.
4. Change again to the curved blade for anything rounded or organic.
5. Finish with a sanding stick, even where the cut already looks clean.

Changing blade three times in a build sounds fussy until you do it once. The cleanup is quicker, not slower, because each cut is being made by the edge that suits it.

If you are starting out

Three things cover most of a build: a number 11 for cutting, a chisel for cleaning up, and a sanding stick at 240 or 400 to finish. Curved and deburring blades become useful once you move on to shaping and conversions, and there is no need to buy them before then.

Four habits worth breaking

Working with a blunt blade. A dull edge drags through plastic instead of parting it, and the give-away is a raised lip along the cut rather than any change in how the knife feels. Blades are consumable. Change them far more often than feels reasonable.

Pressing harder. Pressure is what causes slips and gouges. If a cut needs force, it is the wrong blade or a worn one.

Using the number 11 for everything. The habit this guide exists to break.

Skipping the sanding. Primer is unforgiving. A cut that looks clean in bare plastic will often still show a seam once it is a single colour.

Before you buy

Blade shape decides what the tool does. The handle decides what you can fit, and the two are separate: a light-duty blade will not sit in a heavy-duty handle whatever its shape, so a #24 will not go into a K1.

The compatibility chart on our Excel page lists every replacement blade against the handles it fits, so you can check before ordering rather than after.