How to Use a Metal Shim for Perfect Die Cuts

Die cutting brings designs to life with crisp shapes, delicate patterns, and professional-looking layers for card making, scrapbooking, and countless paper crafts. But anyone who has spent an afternoon wrestling with a detailed floral die or a sheet of heavyweight cardstock knows the frustration of incomplete cuts, torn edges, or wasted material. When the pressure across the cutting sandwich isn’t perfectly even, the results can be patchy and disappointing.

Pressure is the invisible force that drives every successful cut, yet it varies with material thickness, die intricacy, and even the machine’s own wear over time. A standard sandwich with cutting plates and a die often fails to deliver consistent contact, particularly for thin metal dies with tight crevices or for dense materials like burlap, leather, or multiple layers of paper. The solution many home crafters and small business owners rely on is simple, affordable, and remarkably effective: a metal shim.

By sliding a precisely engineered metal shim into the die cutting sandwich, you amplify and level out the pressure that reaches the die, turning near-misses into perfectly clean, full cuts. It transforms a machine’s performance without replacing expensive plates or upgrading to a larger press. This article explores everything you need to know about using a metal shim—from how it works and what types exist to step-by-step instructions, compatibility, and troubleshooting tips—so you can achieve flawless die cuts every time.

Quick Answer

A metal shim is a thin metal plate placed into a die cutting sandwich to increase and evenly distribute pressure. It compensates for worn plates, intricate die details, and thicker materials, helping you achieve clean cuts without tearing or multiple passes.

What Is a Metal Shim and How It Improves Your Die Cuts

In the context of home and hobby die cutting, a metal shim is a flat, usually rectangular sheet of metal that measures just a fraction of a millimeter thick. It acts as a pressure adjuster: when slipped between the cutting plates and the die or between the plates themselves, it effectively reduces the gap inside the machine’s roller or press, increasing the downward force the die receives. This principle is borrowed from precision engineering, where shims correct clearance and alignment issues, but adapted for the craft room with safe, easy-to-handle materials like stainless steel or brass.

A metal shim does not bend or compress under load the way a plastic plate might, so it transfers force more directly. When you pass the sandwich through a manual machine’s rollers, the shim rides along, creating a perfectly level, slightly thicker stack. The rollers then exert greater pressure because they must work harder to draw that stack through. In electric machines that use a press mechanism, the shim fills micro-gaps, ensuring that even the tiniest carved details of a die receive firm contact against the cutting mat or plate.

Crafters quickly notice the improvement: intricate dies with many narrow cuts—think lacy mandalas, fine script sentiments, or delicate leaf veins—suddenly release their shapes with clean edges, and thick materials like chipboard, felt, or metallic cardstock yield to the die on the first pass instead of requiring multiple runs. The metal shim essentially broadens the capability of an existing machine, letting you tackle a wider range of projects without investing in a second, heavier-duty device.

Types of Metal Shims for Die Cutting Machines

Not all metal shims look or work the same way. Understanding the differences helps you pick the right one for your machine, your preferred cutting sandwich configuration, and the materials you use most often.

Standard Flat Metal Shims

The most common type is a simple, thin plate of stainless steel, often priced as an aftermarket accessory. These shims are typically the size of a standard cutting plate, such as 6 by 8 inches or slightly smaller to avoid catching on the machine’s edge. They come in thicknesses around 0.15 mm to 0.25 mm, though some manufacturers offer thinner or slightly thicker variants. The advantage of a flat metal shim is its uniform thickness, which guarantees even pressure from edge to edge, making it ideal for large background dies or full-card designs.

Magnetic Shims and Platform Adapters

Some shims incorporate a magnetic surface, functioning as a combined alignment tool and pressure booster. A magnetic shim holds dies and materials in place while also adding the necessary thickness. This is especially useful when cutting with wafer-thin dies that can shift as they enter the rollers. While not strictly a plain metal shim, the magnetic version often includes a thin metal core, so it serves a similar pressure-adjusting role. Crafters who work with small, fiddly dies often prefer magnetic shims to prevent misalignment and reduce the number of layers in the sandwich.

Precision Shims for Specific Brands

Several die cutting machine manufacturers produce branded shims designed for their particular roller gap. These may be laser-cut with notches, engraved with grid lines, or sized exactly to the machine bed. While a generic metal shim can work across many manual machines, a precision shim tailored for a specific platform may offer smoother feeding and less risk of jamming. When opting for a third-party shim, checking that its dimensions are slightly smaller than your machine’s opening is a wise precaution.

DIY Metal Shims

Some experienced crafters make their own metal shims from thin brass or aluminum sheet stock, cut to the needed size and deburred. This approach requires careful measurement and finishing to avoid scratching cutting plates or damaging the machine’s rollers. Using food-grade or craft-safe metals is important, and any DIY shim should be tested with inexpensive materials first. If you choose this path, keep the thickness consistent and never use a metal sheet that can rust.

Compatibility and Machine Considerations

A metal shim can be used with many popular die cutting machines, but the method and safety vary depending on the machine’s mechanism. Knowing how your machine works will help you avoid damage and get the best results.

Manual Roller Machines

Manual machines like the Sizzix Big Shot, Spellbinders Platinum, and similar crank-operated models are the most common candidates for a metal shim. Because you control the force by turning a handle, you can feel any resistance and stop immediately if the sandwich is too tight. A metal shim in a manual machine typically sits between two cutting plates or under a platform, and you can add or remove it as needed without any electronic feedback systems interfering. Always place the shim on a flat surface and ensure the edges are not protruding, as that could catch on the machine frame and cause a jam.

Electric Press Machines

Some electric die cutting machines, such as the Cricut Cuttlebug (when motorized) or the Gemini series, use a motorised press with a set opening height. Adding a metal shim to these sandwiches requires extra caution because the motor may not stop if the pressure becomes excessive. However, many owners successfully use a thin metal shim on these platforms after verifying the manufacturer’s guidelines. The key is to never force the machine; if the plates are difficult to pull out or the motor sounds strained, the shim thickness should be reduced or the sandwich reconfigured. When in doubt, test with a scrap piece and watch for any signs of stress.

Automatic Feed and Scan-Controlled Machines

Electronic cutting machines that rely on drag knives, such as the Cricut Maker and Silhouette Cameo, do not use pressure rollers in the same way and generally do not require a metal shim for cutting. However, some crafters use thin metal shims with embossing or debossing attachments to add pressure when using non-blade tools. This is an advanced technique and should only be attempted after thoroughly reading the machine’s manual and online user feedback, because incorrect use can void warranties. For most die cutting with steel-rule or wafer-thin dies, a metal shim is intended for the manual or press-style platforms, not for drag-knife mat cutters.

How to Use a Metal Shim Step by Step

Achieving perfect die cuts with a metal shim is a matter of layering your sandwich in the right order and making small adjustments. Follow this sequence for consistent, clean results.

Step 1: Start With a Clean, Flat Workspace

Before you begin, ensure your cutting plates are clean, flat, and free of paper dust or adhesive residue. A warped or sticky plate can defeat the purpose of a metal shim by introducing new pressure irregularities. Wipe all surfaces, including the shim itself, with a soft, dry cloth or a slightly damp cloth if necessary, then dry thoroughly. A tiny speck of grit on a metal shim can leave a permanent indentation on your cutting plates.

Step 2: Assemble Your Basic Sandwich Without the Shim

Lay down the base cutting plate, place your die facing upward on it, then add your cardstock, paper, or fabric on top of the die. Cover with the second cutting plate. Run this assembly through the machine once without the metal shim and note the result. If the cut is nearly complete but a few areas remain attached, you have the perfect opportunity to introduce the metal shim. If the cut failed entirely, your sandwich might already be too thin, so adjusting before adding the shim is a better strategy.

Step 3: Insert the Metal Shim

Place the metal shim inside the sandwich. The most common placement is directly on top of the die-cutting plate that sits above the material, adding a uniform layer of thickness. Some machines work better if the shim is placed between the upper cutting plate and the material, while others prefer it under the bottom plate. Experiment with scrap paper to find the sweet spot for your specific machine. A thin metal shim around 0.15 mm is a good starting point.

Step 4: Test, Evaluate, and Adjust

Run the sandwich through slowly. If the cut is now perfect, note the configuration. If small sections are still uncut, you can carefully add a second thin metal shim or a piece of cardstock as a temporary shim. Always increase thickness in tiny increments, because too much pressure can cut through the upper plate or pinch the material inside the die, making it hard to release. A useful test is the “heartbeat” tension: you should feel consistent resistance as the sandwich passes through a manual machine, not a heavy thud that requires forcing the handle.

Tips for Clean Cuts Every Time

Incorporating a metal shim into your routine is simple, but a few expert habits can keep your projects flawless and your equipment in top shape.

Rotate your cutting plates regularly. Plates develop subtle bows and dips with use, and a metal shim works best when the sandwich is as close to flat as possible. If one plate is noticeably thinner in the middle, flipping it or swapping it out before adding the shim can prevent inconsistent pressure lines.

Use a piece of wax paper or a dryer sheet between the die and the material when cutting intricate designs with fine openings. This reduces static and helps the tiny cutout bits release, so you do not compensate by adding extra shim pressure unnecessarily. The metal shim should enhance the cut, not work harder to punch out debris.

Keep a journal of your successful sandwich recipes. Write down the exact plate order, shim thickness, and material type for each tricky die. This turns trial-and-error into a repeatable process and saves time when you rotate between delicate vellum, textured watercolor paper, and thin leather. With a metal shim, the difference between one extra layer and none can be the margin between a perfect cut and a ruined sheet.

Common Metal Shim Mistakes and How to Avoid Them

Even with the best intentions, a few missteps can turn a metal shim from a helpful tool into a source of frustration. Recognising these pitfalls will keep your crafting smooth and your machine safe.

One frequent error is stacking too many shims at once. When a single die won’t cut, beginners sometimes pile two or three metal shims along with additional card layers, creating a sandwich that is far too thick for the roller gap. This can bend the shim permanently, damage the machine’s gears or rollers over time, and even shatter a cutting plate. Instead, add just one shim incrementally and, if the cut still fails, check whether the die itself is dull or the material is beyond the machine’s capability.

Another mistake is placing the metal shim in direct contact with the die’s cutting edge. While a shim on top of a protective plate is harmless, a metal shim rubbing directly against a delicate thin metal die can nick or dull the blade. Always sandwich the shim between two cutting plates or between a plate and a protective sheet, never between the die and the material without a barrier unless you are using a specialized die designed for that purpose, which is rare in consumer crafting.

Ignoring uneven wear on cutting plates is also a common oversight. If your shim is perfectly flat but your plates are cupped, the pressure increase will be uneven, leading to partial cuts or even diagonal tear marks. Regularly check plates against a metal ruler and replace them when the bow exceeds a millimetre or two. A metal shim will not compensate for severe warping; it works best within a sound sandwich.

Maintaining Your Metal Shim and Cutting Plates

A metal shim is long-lasting, but a small amount of care extends its life and ensures it performs reliably. Store the shim flat in a sleeve or folder, never leaning against a surface where it could warp. Even a slight bend can introduce a permanent high spot that creates uneven pressure. Clean the shim occasionally with a mild cleanser that does not contain corrosive agents; stainless steel shims can be wiped with rubbing alcohol, while brass shims may tarnish if exposed to moisture, so keep them dry.

When not in use, avoid placing heavy objects on top of the shim. The metal is thin enough to conform to a pile of tools or books, and once deformed it can be difficult to flatten perfectly again. A dedicated storage pocket in a die cutting station or a flat drawer works ideally.

Your cutting plates also last longer when you use a metal shim correctly. Because the shim spreads the pressure, it reduces the tendency of plates to warp from concentrated stress, particularly in the center where most dies sit. Rotating and flipping plates combined with a metal shim can nearly double their usable life before they need replacement.

Final Thoughts on Using a Metal Shim for Flawless Die Cuts

No matter what stage you are at in your crafting journey, a metal shim is one of the most practical, budget-friendly tools you can add to your kit. It bridges the gap between a machine that almost works and one that delivers reliably beautiful results, opening doors to intricate techniques and luxurious materials without a major purchase. By understanding the different types, carefully inserting the shim into your cutting sandwich, and adopting good maintenance habits, you turn a tiny sheet of metal into a powerhouse accessory that saves time, reduces waste, and makes every die cut a success.

Whether you are embossing foil, cutting layers of wool felt for a baby mobile, or producing dozens of identical card fronts for a small business, a metal shim gives you the control to fine-tune pressure exactly where you need it. Your craft deserves that final touch of precision, and a metal shim helps you reach it.

FAQ

Can I use a metal shim with any die cutting machine?

Most manual roller-type machines accept a metal shim without issue. Electric press machines and some digital cutters can also use a shim, but always check the manufacturer’s guidelines. Machines that rely on drag knives for cutting do not typically need a shim and may be damaged by an improper sandwich.

How many metal shims can I add to my sandwich?

Start with one thin metal shim and test the cut. If necessary, add a second shim or a paper layer gradually, but avoid building a sandwich so thick that the rollers resist or the motor strains. Overloading can damage your machine and plates.

What thickness of metal shim works best for intricate dies?

A shim around 0.15 mm to 0.2 mm is a good starting point for finely detailed dies. Very thin shims increase pressure slightly without overwhelming delicate cuts, while thicker shims may be needed for heavy chipboard or multiple layers.

Can a metal shim damage my cutting plates?

A properly placed metal shim that sits between the cutting plates does not damage them; it spreads pressure evenly and can actually prolong plate life. Avoid placing a shim directly against a die’s cutting edge, and always check for debris that could press into the plastic surface.

Do I need a metal shim for every die?

No. Many simple shape dies cut cleanly in a standard sandwich. A metal shim is most helpful when a die has intricate details, when you are cutting dense or thick materials, or when your cutting plates have minor wear and need a small boost in pressure.

Where can I purchase a quality metal shim?

Craft stores and online retailers that sell die cutting accessories usually carry stainless steel or brass shims in standard sizes. Look for shims designed specifically for paper crafting to ensure they are the right thickness and free from sharp edges that could scratch your plates or machine.