Case Study
A local excavation & aggregate contractor in San Luis Obispo County needed a fresh set of excavator bucket ears fabricated to restore tight fit-up, reliable pin engagement, and long service life in tough production work. Bucket ears take constant shock loading and abrasive punishment—so this project focused on precision alignment, correct pin tolerances, and durable finishing that holds up in the field.
Client Goal
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Restore/upgrade bucket attachment performance with properly aligned ears
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Ensure smooth pin fitment and long-term durability under heavy use
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Deliver a clean, professional finish matched to customer/OEM expectations
Scope of Work
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Measure and verify fit-up from the bucket/linkage specifications
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Produce shop layout to confirm geometry and pin centerlines
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CNC plasma cut steel plate components
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Fabricate, weld, reinforce, and clean up critical clearances
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Surface prep and paint for corrosion resistance and professional appearance
Client
a local excavation & aggregate contractor in SLO county
City
San Luis Obispo
Process
1) Measurement & Fit-Up Verification
We captured accurate measurements from the bucket/linkage to confirm pin sizing, spacing, and alignment. This step sets the whole project up for success—because a “close enough” ear becomes a “why does this bind?” ear the minute it hits the jobsite.
2) Shop Drawings & Layout
Measurements were translated into shop drawings/cut layouts to verify plate thickness, ear geometry, and pin locations before steel was cut. This reduces rework and ensures the assembly matches the real-world machine, not a best-guess.
3) Plasma Table Cutting
We cut the steel components on a CNC plasma table for repeatability and clean edges—especially important for keeping the ear profiles consistent side-to-side.
4) Fabrication, Welding, and Finish Work
Components were fit, welded, and reinforced as needed. Throughout welding, we managed heat input to control movement and protect alignment. Final grinding and cleanup ensured proper clearances and smooth operation.
5) Surface Prep & Paint
After fabrication, we prepped and painted the assembly to improve corrosion resistance and extend service life—often matched to customer/OEM color requirements.
Challenges
Alignment + Pin Tolerances During Welding
One of the primary challenges with excavator bucket ears is maintaining precise alignment and pin tolerances through the welding process. Heat input can cause material movement, and even minor distortion can create pin bind, uneven wear, or premature failure.
How we addressed it: careful sequencing, controlled heat input, and fit-up verification during assembly to keep everything tracking true.
Results
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Accurate pin alignment for smooth assembly and operation
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Durable, reinforced structure designed for heavy field use
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Clean finish and protective paint for longevity and a professional look
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Reduced downtime risk by delivering a component that installs cleanly and runs right
This photo shows our CNC plasma table cutting thick steel plate for the excavator bucket ear build. The torch head is positioned over the workpiece with layout lines and circular profiles visible on the plate—these marks guide the cut geometry for consistent ear shape, bushing locations, and edge prep. CNC cutting is a major advantage on parts like bucket ears because it delivers repeatable accuracy from piece to piece and creates clean, consistent edges that speed up fit-up during fabrication. The controlled process helps ensure that critical features (like pin centerlines and plate symmetry) begin correctly before welding ever starts.
Here, a fabricator is performing fit-up verification on the bucket ear assembly at a heavy-duty welding table. The ear plates and machined ring/bushing areas are being checked for spacing, parallel alignment, and pin-center consistency—the kind of details that determine whether a bucket pins on smoothly or fights you every time. This stage is especially important because bucket ears must hold tight tolerances while still surviving heavy shock loads in the field. You can also see supporting components and tools staged nearby, reflecting a controlled assembly workflow where we confirm geometry before final welding and reinforcement. This is the “measure twice, weld once” moment that helps prevent pin bind, uneven wear, and premature failure.
This final image shows the completed excavator bucket ear assembly after fabrication, welding, cleanup, and paint. The ears are finished in a bright yellow protective coating (often matched to customer or OEM color preferences) to help resist corrosion and extend service life in harsh operating conditions. The installed pins and clean geometry highlight the end goal of the entire process: smooth engagement, accurate alignment, and durable performance under load. The assembly is staged in the shop for final review before delivery—showing a professional finish, strong weld integrity, and attention to details that matter once the attachment is back in production work.