--- title: "What Are Slotted Shims (Horseshoe) Used For?" description: "Slotted Shims (Horseshoe) (Trade series (slotted alignment shim)) are used for correcting the alignment of a machine on its foundation by stacking calibrated…" url: https://engineeringhardware.com/applications/slotted-shims-horseshoe/ source: Engineering Hardware & Fasteners --- # What Are Slotted Shims (Horseshoe) Used For? Standoffs & Spacers · Trade series (slotted alignment shim) · Application guide Typical applications, the industries that specify slotted shims (horseshoe), and how to choose the right size, material and finish for the joint. Slotted Shims (Horseshoe) are used for correcting the alignment of a machine on its foundation by stacking calibrated thicknesses under its feet. They are manufactured to Trade series (slotted alignment shim), and selection is driven by the nominal size, the fit and tolerance the assembly requires, and the service environment. - **Primary duty:** Correcting the alignment of a machine on its foundation by stacking calibrated thicknesses under its feet - **Governing standard:** Trade series (slotted alignment shim) - **Nominal size range:** 9 mm to 17 mm - **Category:** Standoffs & Spacers Application notes are general engineering guidance. Verify the property class and any approval requirement against your own design calculation. ![What Are Slotted Shims (Horseshoe) Used For? application image](https://engineeringhardware.com/wp-content/uploads/2026/09/Slotted-Shims-Applications.webp) Slotted Shims (Horseshoe) are used primarily for correcting the alignment of a machine on its foundation by stacking calibrated thicknesses under its feet. This page lists the industries and assemblies where they are specified, the selection criteria that matter for each application, installation practice, and the cases where a different fastener type is the correct choice. Parts are supplied to Trade series (slotted alignment shim). Stocked across roughly 9 mm to 17 mm, they cover general to heavy-duty work. ## Typical Applications for Slotted Shims (Horseshoe) The most common settings where these are specified: - **Electronics assembly:** holding boards off a chassis and stacking multiple boards at a fixed pitch. - **Enclosures & panels:** spacing a fascia, guard or label plate off the surface behind it. - **Machine alignment:** setting and correcting the height of a component on its mounting. - **General machine building:** fastening covers, brackets, motors and sub-assemblies on production equipment. - **Maintenance & repair (MRO):** a stocked size for servicing existing plant where the original fastener spec must be matched. 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This product spans 9 mm–17 mm; check the full table below for the exact dimensions of each size. - **Material:** Choose the material and finish for the service environment — plated steel for general use, stainless for corrosion resistance. - **Environment:** For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient. - **Standard:** This product is supplied to Trade series (slotted alignment shim). Quoting the standard on your order guarantees interchangeable dimensions between suppliers. ## Where Slotted Shims (Horseshoe) Are Not the Right Choice Match the fastener to the load, environment and whether the joint must be reopened; the wrong class or style is the usual cause of joint failure. Custom manufacturing · Made to drawing ## Need a slotted shims (horseshoe) outside the standard range? Dimensions, material, finish and form are specified from the drawing — a standoff & spacer outside the standard range is a variation on existing tooling rather than a new design. Made by tapping or turning. Minimum order from 2,000 pieces; samples within 7 days of drawing approval. [Custom standoff & spacer manufacturing](https://engineeringhardware.com/custom/standoffs-spacers/)[Send a drawing](https://engineeringhardware.com/custom/standoffs-spacers/#rfq) ## Technical Drawing Dimensioned line drawing of 9 Slotted Shims (Horseshoe) to Trade series (slotted alignment shim). Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected. - **Width A (mm):** 38 - **Length (mm):** 38 - **Thickness t (mm):** 0.05 - **Material:** Stainless 304 - **Colour code:** None (bright) - **Typical use:** Motor foot alignment ## Dimensions & Specifications (Trade series (slotted alignment shim)) | Slot width (mm) | Width A (mm) | Length (mm) | Thickness t (mm) | Material | Colour code | Typical use | | --- | --- | --- | --- | --- | --- | --- | | 9 | 38 | 38 | 0.05 | Stainless 304 | None (bright) | Motor foot alignment | | 9 | 38 | 38 | 0.10 | Stainless 304 | None (bright) | Motor foot alignment | | 13 | 50 | 50 | 0.25 | Stainless 304 | None (bright) | Pump / gearbox feet | | 13 | 50 | 50 | 0.50 | Stainless 304 | None (bright) | Pump / gearbox feet | | 17 | 63 | 63 | 0.75 | Stainless 304 | None (bright) | Heavy machine bases | | 17 | 63 | 63 | 1.00 | Stainless 304 | None (bright) | Heavy machine bases | Inside the plant ## Manufactured in our own plant This part is cold-formed, threaded, heat-treated and finished in-house. The stages below are where its class and finish are actually decided. 1. ![Wire rod feeding into a cold heading machine](https://engineeringhardware.com/wp-content/uploads/2026/08/09-wire-rod-feed-cold-heading-machine.webp) 01 **Cold heading** Wire rod is drawn to size and cold-formed into blanks. Forming rather than cutting keeps the grain flow continuous around the head, which is where a bolt is most likely to fail. Head dimensions and under-head radius checked at set-up and per shift. 2. ![Thread rolling machine producing bolt threads](https://engineeringhardware.com/wp-content/uploads/2026/08/03-thread-rolling-machine-bolt-production.webp) 02 **Thread rolling** Threads are rolled between hardened dies rather than cut. Rolled threads are stronger in fatigue than cut threads and hold pitch and flank angle far more consistently across a batch. Go / no-go ring gauges to ISO 965 tolerance class 6g. 3. ![Baskets of bolts staged for heat treatment](https://engineeringhardware.com/wp-content/uploads/2026/08/05-heat-treatment-baskets-black-bolts.webp) 03 **Heat treatment** Quench-and-temper brings carbon and alloy steel to the property class ordered — 8.8, 10.9 or 12.9 — with the furnace charge tracked so a finished lot can be traced back to it. Core hardness and tensile tested per lot to ISO 898-1. 4. ![Zinc plated bolts in a treatment basket](https://engineeringhardware.com/wp-content/uploads/2026/08/23-zinc-plated-bolts-treatment-basket.webp) 04 **Surface treatment** Zinc, zinc-nickel, hot-dip galvanizing, black oxide, phosphate and Dacromet, selected against the service environment rather than against the price list. Coating thickness and neutral salt spray hours to ISO 9227. ## Frequently Asked Questions ### What are Slotted Shims (Horseshoe) used for? Correcting the alignment of a machine on its foundation by stacking calibrated thicknesses under its feet. They are supplied to Trade series (slotted alignment shim). ### Which industries use Slotted Shims (Horseshoe)? They are commonly specified in machine alignment, general machine building and maintenance & repair (mro), among other sectors. ### How do I choose the right size of Slotted Shims (Horseshoe)? Select on nominal size and on the fit the assembly requires. This product is available from 9 mm to 17 mm; the full dimension table on this page lists each size. ### What material should Slotted Shims (Horseshoe) be for outdoor use? For damp, coastal or chemical environments specify A4 (316) stainless or a suitably coated steel. For indoor or dry use, A2 (304) stainless or zinc-plated steel is normally adequate. ### Can I get a quote for Slotted Shims (Horseshoe) in the size and material I need? Yes. Use the technical drawing and quote form on this page to set the size and options, then send the exact configuration to our team for pricing and lead time. ## Related Pages Product page: [Slotted Shims (Horseshoe) — specifications & sizes](https://engineeringhardware.com/fastener/slotted-shims-horseshoe/) ### Slotted Shims (Horseshoe) Specification Guides ### Related Fastener Applications