{"id":3541,"date":"2026-10-21T12:52:51","date_gmt":"2026-10-21T04:52:51","guid":{"rendered":"http:\/\/www.unchainedgospel.com\/blog\/?p=3541"},"modified":"2026-10-21T12:52:51","modified_gmt":"2026-10-21T04:52:51","slug":"how-do-different-manufacturing-processes-affect-the-properties-of-multi-layer-shim-46e4-328b4f","status":"publish","type":"post","link":"http:\/\/www.unchainedgospel.com\/blog\/2026\/10\/21\/how-do-different-manufacturing-processes-affect-the-properties-of-multi-layer-shim-46e4-328b4f\/","title":{"rendered":"How do different manufacturing processes affect the properties of Multi – layer Shim?"},"content":{"rendered":"

What\u2019s up, shim squad! If you\u2019re working in aerospace, automotive, medical devices, or even heavy industrial machinery, you know multi-layer shims aren\u2019t just \u201cthin little washers.\u201d They\u2019re the unsung heroes that keep precision components aligned\u2014one tiny, perfectly sized layer at a time. As a multi-layer shim supplier who\u2019s been in this game for over a decade, I get it: when a customer calls panicking because a shim\u2019s too soft, or it rusts too fast, or it doesn\u2019t hold up under 10,000 psi of pressure, it almost always boils down to how we made it. Today, I\u2019m breaking down exactly how different manufacturing processes shape a multi-layer shim\u2019s properties\u2014no stuffy engineering jargon, just real talk from someone who\u2019s watched hundreds of shims roll off the line (and the bad ones get sent back). Multi-layer Shim<\/a><\/p>\n

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First, let\u2019s ground this: what is a multi-layer shim, anyway? It\u2019s not a stack of individual single-layer shims you glue together (though that\u2019s a cheap, hacky way to do it\u2014more on that in a sec). It\u2019s a single, integrated part made by bonding 2+ sheets of metal (or sometimes other materials) into one uniform component. The layers can be all the same metal (like two 301 stainless steel sheets) or mixed (steel + aluminum, or even steel + polymer for non-marring applications). The manufacturing process isn\u2019t just about putting layers together\u2014it\u2019s about how those layers fuse, how thick each one is, and how the end product acts under stress. Let\u2019s go through the main processes we use here, and how each impacts the shim\u2019s core properties: strength, flexibility, corrosion resistance, and precision.<\/p>\n

1. Photochemical Machining (PCM) \u2014 The Gold Standard for Precision<\/h3>\n

Let\u2019s start with the process we use most for our high-volume, tight-tolerance orders: photochemical machining, or as we call it around here, \u201cphoto etching.\u201d Here\u2019s how it works: we take a flat sheet of the base material, coat both sides with a light-sensitive resist, print a custom stencil of the shim shape on the resist, blast it with UV light, then dip it in a chemical etchant that eats away the unprotected metal. No cutting, no bending, no physical stress on the material.<\/p>\n

So what does that do to the shim\u2019s properties? First, precision. We can hold tolerances as tight as \u00b10.0001 inches\u2014way better than any mechanical process. That\u2019s why aerospace companies love PCM shims: they need shims that fit perfectly in jet engine turbine gaps, where even a 0.0005-inch mismatch can cost millions in fuel efficiency. Flexibility? PCM shims stay super consistent. Since we never bend or stamp the material, the grain structure of the metal stays exactly as it was when it came off the mill. No warping, no work-hardening (that\u2019s when metal gets hard and brittle from being bent or pressed too much).<\/p>\n

Wait, but what about drawbacks? PCM works best on thin materials\u2014usually 0.001 to 0.06 inches total. If you need a thicker shim, you can stack etched layers, but wait\u2014no, with PCM, you can actually machine multiple layers at once if they\u2019re the same thickness, fusing them during etching. The bonding here is molecular, not adhesive, so there\u2019s no weak seam between layers. Corrosion resistance? Also solid. No sharp edges from stamping that can trap moisture, no exposed adhesive that breaks down over time. Our aerospace clients swear by PCM shims because they don\u2019t degrade at high altitudes or extreme temps.<\/p>\n

2. Stamping (Mechanical Pressing) \u2014 The Low-Cost Workhorse<\/h3>\n

If you\u2019re looking for a shim for less demanding applications\u2014like assembling a pair of industrial pumps or HVAC units\u2014stamping is way cheaper. Stamping uses a die and a mechanical press to cut and shape the shim from a metal sheet. You can do single layers or stack multiple sheets, but most stamping jobs just punch a shape out of a stack of pre-cut layers, then you have to bond them with epoxy.<\/p>\n

Here\u2019s where the properties get tricky. Stamping work-hardens the metal. When the die slams down on the sheet, it compresses the metal along the edges, making that area way harder and more brittle than the rest. That means if the shim\u2019s going to flex (like around a rotating shaft), the stamped edges can crack over time. We see this all the time with customers who switch to stamping shims to save money, then come back 6 months later saying their shims are breaking. Also, the tolerance? Stamping can only hold \u00b10.002 inches, max. Not bad for HVAC, but garbage for medical devices where a 0.001-inch error can mess up a pacemaker\u2019s internal parts.<\/p>\n

Another big one: bonding. The epoxy used to stick stamped layers together can delaminate under high heat or pressure. We had a client last year in food processing\u2014they were using stamped epoxy-bonded shims in a mixer that hit 180\u00b0F. The epoxy broke down, the layers separated, and metal shavings got into the product. Oops. Stamping is great for low-stakes, low-cost needs, but if you need reliability, it\u2019s not the way to go.<\/p>\n

3. EDM (Electrical Discharge Machining) \u2014 For Weird Shapes and Exotics<\/h3>\n

EDM is the fancy process for when you need a shim out of a super tough material\u2014like titanium, Inconel, or carbide\u2014that\u2019s impossible to stamp or etch. How it works: you use a series of electrical sparks to erode the metal into the shape you want, no physical contact between the tool and the workpiece. That means you can make super intricate shapes, like shims with tiny holes for cable ties, or custom profiles for turbine blades.<\/p>\n

Properties here: EDM doesn\u2019t work-harden the metal like stamping, which is a win. But wait\u2014there\u2019s a thing called \u201crecast layer\u201d from the sparks. The sparks melt a tiny bit of the metal, which re-solidifies on the surface. That recast layer is brittle, and if you don\u2019t remove it (we do this with a light chemical polish), the shim can crack under cyclic stress. Also, EDM is slow\u2014way slower than PCM or stamping. So it\u2019s not for high volume. Our clients use EDM for one-off prototype parts or specialty aerospace components where they can\u2019t use standard materials. Corrosion resistance? The recast layer is a problem here\u2014if it\u2019s left on, it can pit and rust way faster than the base material. That\u2019s why we always do a post-EDM polish for any shim going into a corrosive environment.<\/p>\n

4. Bonded Layer Stacking (Adhesive or Diffusion Bonding) \u2014 The Budget Multi-Layer Option<\/h3>\n

Wait, I mentioned this earlier\u2014bonded stacking is the \u201cDIY\u201d way to make a multi-layer shim, but it\u2019s a manufacturing process too, just not one we recommend for critical applications. There are two types here: adhesive bonding (gluing layers together) and diffusion bonding (heating layers under pressure so the metal atoms fuse together, no adhesive).<\/p>\n

Adhesive bonded shims are cheap, but as I said, the glue is the weak point. We had a car manufacturer a few years back use adhesive multi-layer shims in their transmission. After 20,000 miles, the glue broke down, layers shifted, and the transmission failed. Diffusion bonding is better, but it\u2019s expensive. It requires high heat and pressure, so it only works on certain metals, and it\u2019s hard to get consistent thickness between layers. The benefit? You can make thicker shims than PCM, but for most applications, the precision of PCM beats the slightly higher strength of diffusion bonded shims.<\/p>\n

How This All Matters for Your<\/em> Shims<\/h3>\n

Let\u2019s tie this back to what you actually care about. If you\u2019re a small business owner putting together HVAC units and you just need shims that hold two metal parts in place\u2014stamped epoxy-bonded is fine, it\u2019ll save you 30% vs. PCM. But if you\u2019re a medical device engineer building a surgical robot, you need shims that don\u2019t pit, don\u2019t delaminate, and fit exactly\u2014PCM is non-negotiable. Aerospace? You guessed it: PCM all the way, because even one bad shim can lead to a disaster.<\/p>\n

The big mistake I see customers make is assuming all multi-layer shims are the same. They\u2019re not. The process doesn\u2019t just affect how the shim looks\u2014it affects how it performs under stress, heat, and corrosion. We once had a client who tried to switch from our PCM shims to a cheaper stamped one for their agricultural equipment. 3 months later, they were back, saying the stamped shims cracked every time they ran the tractor through rocky fields. The work-hardened edges from stamping were the culprit. That\u2019s the kind of problem we fix every day.<\/p>\n

Another thing: material choice + manufacturing process = even more properties. For example, if you want a shim that\u2019s non-marring (so it doesn\u2019t scratch the part it\u2019s going between), you\u2019d use a polymer film layer. With PCM, we can etch the metal layer first, then bond the polymer layer to the back, making a single integrated shim. If you tried to do that with stamping, the polymer would get torn during the cutting process. That\u2019s why PCM is the only way for non-marring multi-layer shims.<\/p>\n

Why We Do Things This Way<\/h3>\n

At the end of the day, our whole job isn\u2019t just to sell you shims\u2014it\u2019s to make sure you get the right shim for your job. We don\u2019t push PCM on everyone, but we do make sure you know when it\u2019s necessary. Stamping is great for low-volume, low-precision jobs, but we\u2019ll always be honest if it\u2019s not going to work for your application.<\/p>\n

If you\u2019re tired of shims that don\u2019t hold up, or you\u2019re working on a new project and you\u2019re not sure which process is right for your multi-layer shim\u2014hit us up to talk through your needs. We\u2019ve got 10+ years of experience troubleshooting everything from prototype parts to mass-produced industrial components, and we\u2019ll help you find the perfect fit.<\/p>\n

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Don\u2019t settle for one-size-fits-all shims. The right manufacturing process makes all the difference between a part that works for years, and one that\u2019s a headache from day one.<\/p>\n

Truck Electrical Sensor<\/a> References<\/p>\n

    \n
  1. Digital Manufacturing and Design Engineering. Photochemical Machining: Process Capabilities and Applications. 2021.<\/li>\n
  2. Society of Manufacturing Engineers. Stamping Technology: Work-Hardening and Material Properties. 2019.<\/li>\n
  3. ASM International. Electrical Discharge Machining: Surface Integrity Considerations. 2020.<\/li>\n
  4. Materials Science and Engineering: Multi-Layer Bonded Metals for Structural Applications. 2022.<\/li>\n<\/ol>\n
    \n

    Hangzhou Jida Auto Fitting Trading Co., Ltd.<\/a><\/p>\n

    Address: No.588 LouYing Road, LouTa Town, Xiaoshan, HangZhou, Zhejiang China.
    E-mail: Karl.chen@jidaauto.com
    WebSite:     https:\/\/www.jd-fineblanking.com\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

    What\u2019s up, shim squad! If you\u2019re working in aerospace, automotive, medical devices, or even heavy industrial … How do different manufacturing processes affect the properties of Multi – layer Shim?<\/span>Read more<\/a><\/p>\n","protected":false},"author":94,"featured_media":3541,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[3504],"class_list":["post-3541","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry","tag-multi-layer-shim-49af-32bef1"],"_links":{"self":[{"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/posts\/3541","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/users\/94"}],"replies":[{"embeddable":true,"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/comments?post=3541"}],"version-history":[{"count":0,"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/posts\/3541\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/posts\/3541"}],"wp:attachment":[{"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/media?parent=3541"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/categories?post=3541"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.unchainedgospel.com\/blog\/wp-json\/wp\/v2\/tags?post=3541"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}