Shimming the Cutting Sandwich for Consistent Die Cutting
Die cutting is a rewarding craft, but achieving a clean cut on every project requires precise pressure. One of the most effective techniques for fine-tuning your manual or electric die cutting machine is shimming the cutting sandwich. This method involves adding thin layers to the stack of plates, dies, and paper to adjust the pressure applied by the rollers. Without proper pressure, intricate dies may leave uncut fibers, tear delicate cardstock, or fail to emboss deeply enough. Shimming gives you control over these outcomes and helps you avoid frustration during card making, scrapbooking, and other paper crafts.
Many crafters struggle with inconsistent results, especially when switching between different brands of dies, varying paper weights, or using intricate designs with many fine details. A cutting sandwich that works perfectly for a simple steel-rule die on lightweight paper may not provide enough pressure for a detailed wafer-thin die on heavy cardstock. Instead of buying a new machine or accepting poor results, you can often solve the problem by adding a shim. This guide explains when shimming is necessary, how to build a proper shim, and how to troubleshoot common cutting problems using this simple but powerful technique.
Before you begin shimming, it is important to understand the mechanics of your die cutting machine. While manual and electric machines differ in how they drive the plates through the rollers, they all rely on a consistent gap or pressure setting between the rollers. Shimming works by reducing that gap slightly, increasing the force applied to the die. This article focuses on home and hobby die cutting machines, including manual, electric, mini, and portable models. Industrial die cutting presses and factory equipment are outside the scope of this discussion.
Quick Answer
Shimming the cutting sandwich means adding thin material layers to increase pressure for intricate dies or thicker paper. Use paper, cardstock, or specialty shim sheets and test after each addition. Shimming fixes incomplete cuts, uneven pressure, and shallow embossing.
Understanding the Cutting Sandwich
The cutting sandwich is the stack of components that pass through the rollers of a die cutting machine. In a typical manual machine, the sandwich consists of a base plate (often called the platform or cutting plate), then the die with its cutting edge facing up, then the material to be cut (paper or cardstock), and finally a top plate. Some machines use two clear plates, while others may have a dedicated platform and one or two cutting plates. The exact order and number of plates vary by manufacturer and model, so always consult your machine’s manual for the correct base configuration.
The rollers apply pressure to this sandwich as it passes through. The die’s cutting edge presses into the material and ultimately into the opposing plate, slicing the material. If the sandwich is too thin or too thick, the pressure changes. Most machines are designed to cut a standard paper weight, such as 65 lb cardstock, with a standard die. But when you introduce heavier cardstock, multiple layers, or a thicker die, the standard sandwich may not provide enough pressure to cut all the way through. Conversely, if you use very thin material or a die with a very shallow cutting edge, the standard sandwich may apply too much pressure, causing the die to cut into the plate or tear the material.
A shim is an additional layer that you insert into the cutting sandwich to increase the overall thickness, thereby increasing the pressure. Shims are usually placed between the top plate and the material, or between the bottom plate and the die, depending on the machine and the type of shim. The goal is to create a slightly thicker sandwich so that the rollers squeeze harder on the die. The right shim thickness compensates for variations in die height, material thickness, or wear on the cutting plates.
Why Consistent Pressure Matters for Intricate Dies
Intricate dies, such as those with delicate filigree patterns, fine lines, or many small cutouts, are more sensitive to pressure inconsistencies than simple large shapes. These dies have many narrow cutting edges that must all penetrate the material evenly. If the pressure is too low, some areas may not cut through completely, leaving a partially attached piece that tears when you try to remove it. If the pressure is too high, the fine lines may cut into the plate or stretch the material, causing distortion.
Consistent pressure across the entire die face is essential for clean results. Even a small variation in plate thickness, a slight warp in the die, or an unevenly rolled sandwich can lead to incomplete cuts in the center or along the edges. Shimming can help compensate for these variations by adding extra pressure where needed. In some cases, crafters use a partial shim—a piece of paper or tape placed only under the low-pressure area—to even out the pressure distribution. This technique is particularly useful for large dies that cut well on the edges but not in the center, or for dies with intricate details in one specific region.
Another factor is the type of die. Steel-rule dies are thicker and more rigid, often requiring less shimming because their cutting edge is raised higher. Wafer-thin dies (also called chem-etch or thin metal dies) are lower profile and may need shimming more frequently, especially on thicker materials. Embossing folders also benefit from shimming when a deeper emboss is desired. By understanding how pressure affects different die types, you can use shimming more effectively.
When to Add Shims
Knowing when to add a shim is as important as knowing how. The most common sign is an incomplete cut: the die leaves an impression but does not cut all the way through the material, leaving the piece stuck or requiring you to finish the cut with scissors or a craft knife. This happens frequently when using heavy cardstock (100 lb or more), watercolor paper, or multiple layers of paper. It can also occur when the die is new and has not been sharpened, or when the cutting plates are worn and have become thinner over time.
Another indicator is shallow embossing. If you are using an embossing folder and the design comes out barely visible or uneven, the pressure may be too low. Adding a shim can increase the depth of the emboss. Similarly, if you are cutting fabric or felt, these materials compress differently than paper and may require additional pressure to cut cleanly. Leather and thin cork can also be die cut at home, but they often need shims to compensate for their density.
You may also need to shim when switching between different brands of dies or plates. Not all cutting plates are exactly the same thickness, and some third-party plates may be slightly thinner than the original equipment plates. A shim can make up the difference. Finally, if you notice that one side of the die cuts better than the other, a partial shim can help balance the pressure. Before adding a full shim, always try repositioning the die or material—sometimes the issue is simply uneven placement on the plate.
How to Shim the Cutting Sandwich
Shimming the cutting sandwich is a straightforward process, but it requires patience and testing. The first step is to establish a baseline. Run your die cutting machine with the standard sandwich and your intended material, using a die that you know should cut cleanly. Observe the result. If the cut is incomplete, add one thin shim and run it again. If the cut is now too deep or the die cuts into the plate, you have added too much. The goal is to find the minimal amount of shim that produces a clean cut without damaging the plates or the die.
The most common shim materials are cardstock, copy paper, or specialty shim sheets sold by some machine manufacturers. Copy paper is approximately 0.1 mm thick, while light cardstock is around 0.2–0.3 mm. Specialty shim sheets may be made of plastic or metal and come in precise thicknesses. Start with a single piece of copy paper or lightweight cardstock. Place it on top of the material to be cut, between the material and the top cutting plate. This is the easiest position because it directly increases the pressure on the die without interfering with the die’s placement.
If your machine uses a two-plate sandwich where the die sits on the bottom plate, you can also place the shim underneath the bottom plate, but this may raise the entire stack and could cause clearance issues. Placing the shim on top of the material is usually safer and more effective. Some machines have a designated shim plate that goes between the die and the bottom plate or between the material and the top plate—refer to your manual. Always run the shim through the machine in the same orientation as the rest of the sandwich to avoid jams.
Test after each addition. Cut a small scrap of the same material with the same die, and check for a clean release. If the cut is still not complete, add another thin shim. If you notice the die cutting into the top plate or leaving deep marks, remove a shim. Keep a log of which materials and dies require which shim configuration. This will save time in future projects. For partial pressure issues, cut a shim that covers only the area where the cut is incomplete, such as the center of the die. Tape it in place with removable tape and test again. This technique can compensate for a warped die or a machine with uneven roller pressure.
Shim Placement Options
Where you place the shim affects the pressure distribution. The three main positions are:
1. On top of the material – between the material and the top cutting plate. This increases overall pressure evenly and is the most common method.
2. Under the die – between the bottom plate and the die. This raises the die slightly, which can help if the die itself is thinner than standard.
3. Inside the embossing folder – for embossing, place the shim inside the folder on top of the paper, or between the folder and the top plate. Some machines require a different configuration for embossing versus cutting.
Experiment with these positions to find what works best for your machine and die combination. Never force a sandwich through the machine if it feels too tight, as this can damage the rollers or jam the plates.
Choosing the Right Shim Material
The material you choose for your shim depends on how much pressure adjustment you need and how durable you want the shim to be. Paper and cardstock are inexpensive and widely available, but they compress over time and may need to be replaced frequently. They are perfect for occasional adjustments or for testing because you can add or remove layers easily. However, paper shims can also absorb moisture from the air, changing their thickness slightly, which may affect consistency in humid environments.
Specialty shim sheets made of plastic or metal offer more consistent thickness and longevity. Plastic shims, such as those made from polyester or polypropylene, are durable, moisture-resistant, and available in exact thicknesses like 0.2 mm or 0.3 mm. Metal shims, often made of stainless steel or aluminum, are extremely thin and precise, but they can be expensive and may scratch plates if not handled carefully. Some crafters use old credit cards or gift cards as shims, but these are much thicker and should only be used if you need a significant pressure increase and your machine can handle it.
Do not use materials that are too thick or uneven, such as corrugated cardboard, folded fabric, or multiple layers of heavy cardstock all at once. These can create excessive pressure and damage your machine. Start thin and build up gradually. If you need a permanent shim for a frequently used die and material combination, consider investing in a dedicated metal or plastic shim of the correct thickness. Mark it with the die name and material weight so you can identify it quickly.
Troubleshooting Common Die Cutting Issues with Shims
Shimming can resolve many common cutting problems, but not all issues are caused by insufficient pressure. Before adding a shim, rule out other causes such as a dull die, a bent cutting edge, or incorrect sandwich order. Here are specific issues and how shimming can help.
Incomplete Cuts
If the die leaves an impression but does not cut through the material completely, add one thin shim and test again. If the problem persists, check that the die is not warped and that the cutting edge is not dull. For new dies, a light sharpening or running them through aluminum foil may help. Incomplete cuts on only certain areas often indicate uneven pressure, which can be addressed with a partial shim placed under the low-pressure zone.
Torn or Ragged Edges
Torn edges can be a sign of too much pressure, especially on delicate materials like vellum, tissue paper, or thin handmade paper. In this case, you may need to reduce the pressure by removing any existing shims or using a slightly thinner plate. If the tear occurs only on one side, the sandwich may be misaligned or the die may be positioned too close to the plate edge. Reposition and test before changing the shim.
Die Cutting Into the Plate
If the die leaves deep cuts or grooves in your cutting plate, the pressure is too high. This can happen if you added too many shims or if the die is unusually tall. Remove shims until the die cuts the material but does not cut significantly into the plate. Some plate marking is normal over time, but deep cuts can shorten the plate’s life and eventually cause jams. Always use a dedicated cutting plate for cutting and a separate one for embossing to minimize damage.
Uneven Embossing
For embossing folders, if the design is shallow or some areas are not embossed at all, add a shim between the folder and the top plate. You can also place a shim inside the folder behind the paper if the folder has a recessed design. If the embossing looks crushed or the paper is torn, remove the shim. Embossing folders can be sensitive, so test with scrap paper first.
Jamming or Difficulty Turning the Handle
If the sandwich becomes too thick, the rollers may bind and you will have difficulty turning the handle on a manual machine or the motor may strain on an electric machine. If this happens, stop immediately. Remove the sandwich and reduce the number of shims. Never force the sandwich through the machine. A jam can damage the rollers, gears, or motor. Check that all plates are straight and that the die is not overlapping the plate edges.
Step-by-Step Shimming Process
Follow these steps to shim your cutting sandwich safely and effectively.
1. Gather materials: Have your die cutting machine, standard cutting plates, die, material, and a selection of shim materials (copy paper, cardstock, or specialty shims) ready.
2. Set up the baseline sandwich: Assemble the sandwich exactly as recommended in your machine’s manual. Run it through once without any shims. Examine the cut. If it is clean and complete, no shim is needed.
3. Add one thin shim: Place a single piece of copy paper or lightweight cardstock on top of the material, between the material and the top plate. Make sure the shim covers the entire die area, not just part of it, unless you are using a partial shim intentionally.
4. Test again: Run the sandwich through the machine. Do not force it. If it feels excessively tight, stop and remove the shim.
5. Evaluate the result: If the cut is now complete and clean, you have found the right shim. If it is still incomplete, add another thin shim and repeat. If the cut is too deep or the die is cutting into the plate, remove a shim.
6. Record your settings: Once you find the perfect shim configuration for a specific die and material, write it down. Note the number and type of shims, their placement, and any partial shim details. This will make future projects faster.
7. Store shims safely: Keep your shims flat and clean. If using paper, replace them when they become creased or compressed. Plastic and metal shims can be wiped clean and reused indefinitely.
Maintaining Consistent Pressure Over Time
Cutting plates wear down with use. Over time, they become thinner and less flat, which reduces pressure. If you find that you need to add more shims than before to achieve the same cut, it may be time to replace your plates. Most manufacturers recommend flipping or replacing plates after a certain number of passes, but plate life varies widely. Signs of plate wear include deep grooves, warping, and a visible reduction in thickness compared to a new plate.
To maintain consistent pressure, rotate your plates. Use both sides of each plate, flipping them periodically to distribute wear. Many crafters flip their plates after each project or after every dozen passes. If your machine has an adjustable pressure dial, you can use that instead of shims for some adjustments, but shimming remains useful for fine-tuning and for machines without adjustable pressure.
Clean your plates regularly to remove paper dust and adhesive residue, which can build up and affect pressure. A damp cloth and mild soap work well, but make sure the plates are completely dry before use. Avoid using harsh chemicals or abrasive cleaners that could scratch the surface. Also check the die itself for bent edges or accumulated paper fibers, which can cause uneven cutting. A soft brush or a piece of wax paper can help remove debris from intricate dies.
Advanced Shimming Techniques
Once you are comfortable with basic shimming, you can try more advanced techniques to solve specific problems. For large or complex dies, a partial shim can correct pressure imbalances. Cut a piece of cardstock that matches the shape of the low-pressure area—often the center of the die—and place it under the material or under the die in that location. The shim does not have to be precise; a rough shape that covers the problem area is sufficient. Test on scrap paper to see if the pressure evens out.
For multiple dies on one plate, you may need to add individual shims under each die if they have different thicknesses. This is common when mixing brands or types of dies in a single pass. Use small pieces of paper cut slightly larger than the die footprint, and place them between the die and the bottom plate. This raises the lower-profile dies to match the height of the thicker ones, resulting in even cuts across all dies.
Some crafters use a metal shim placed permanently under the bottom plate to compensate for a machine that runs slightly loose. This is a more advanced modification and should only be attempted if you are confident in your machine’s tolerances. A metal shim can also be used to increase pressure for cutting thicker materials like chipboard, but be cautious because excessive pressure can break the die or damage the machine. Always consult your machine’s manual for maximum sandwich thickness and never exceed the recommended limits.
FAQ
What is shimming in die cutting?
Shimming is the technique of adding thin layers of material, such as paper or plastic, to the cutting sandwich to increase the pressure applied by the die cutting machine. This helps achieve clean cuts on thicker materials or with intricate dies.
How many shims should I use?
Start with one thin shim, such as a sheet of copy paper, and test the cut. Add another only if the first did not produce a complete cut. The correct number depends on your machine, die, and material, but most adjustments require only one to three thin shims.
Can I use cardboard as a shim?
It is not recommended because corrugated cardboard is too thick and uneven. It can create excessive pressure and damage your machine. Use copy paper, cardstock, or specialty shim sheets for better control.
Where should I place the shim in the cutting sandwich?
The easiest and most common placement is on top of the material, between the material and the top cutting plate. This increases overall pressure evenly. You can also place a shim under the die or use a partial shim for uneven pressure.
Will shimming damage my die cutting machine?
If done correctly with thin, even shims and careful testing, shimming is safe. However, using too many shims or very thick materials can cause excessive pressure, potentially damaging the rollers, plates, or gears. Always test gradually and never force the sandwich through.
How do I know if I need to replace my cutting plates instead of adding shims?
If you find that you need more and more shims to get the same cut, or if your plates are visibly warped or deeply grooved, it is likely time to replace them. Plates wear down with use and eventually lose their ability to provide proper pressure.
Conclusion
Shimming the cutting sandwich is an essential skill for any die cutting enthusiast. It gives you precise control over the pressure your machine applies, allowing you to cut intricate dies, heavy cardstock, and special materials with confidence. By understanding when to add a shim, where to place it, and how to test safely, you can troubleshoot most common cutting problems without buying new equipment. Remember to start thin, test frequently, and keep a record of your shim settings. With practice, shimming will become a natural part of your die cutting routine, ensuring consistent, beautiful results every time.