Sheet Metal Finishes and Post-Processing

Our sheet metal fabrication service offers a broad range of surface finish treatments and post-processing options to customize your projects.

Sheet Metal Finishing Options


Powder Coating Process

Powder Coating

Powder coating applies a dry powder to the surface of sheet metal parts. Then, they are cured in a large oven to create a hard finish that is tougher than conventional paint. This process improves durability to parts and adds custom color for aesthetic purposes. 

Choose from 50 stocked colors for the fastest turnaround time. Various texture and gloss levels are available. Learn more about powder coating

Example of plating on a sheet metal part


Plating (or coating) options can provide corrosion resistance, improve wear properties, and help with conductivity while enhancing appearance with a quality, uniform finish. 

Available plating options include: 

  • Anodize (type II or type III)
  • Chromate
  • Zinc
  • Passivate
  • Electroless Nickel
  • Tin
Example of silk screening on a part

Silk Screening

Silk screening on sheet metal involves forcing ink through a fine mesh screen containing a stencil that blocks off areas in order to achieve the desired design. Ink is transferred to areas not covered by the stencil onto the metal surface. This process is often used for adding labels, instructions, or decorative patterns to fabricated metal products. 


Sheet Metal Surface Finish Guide

Check out our sheet metal guide for a quick snapshot of our Standard and Cosmetic finishing options available for various sheet metal materials.

Download Guide

Post-Processing Capabilities for Sheet Metal Parts and Assemblies


Hardware Insertion

PEM hardware insertion and riveting are available secondary sheet metal processes. Choose from a library of self-clinching fasteners, including: 

  • Stand-offs
  • Clinch nuts
  • Studs/pins
  • Panel fasteners
Assembly Construction

Order complete assemblies consisting of multiple sheet metal parts. We can deliver your assembly project as independent components, pop-riveted, or fully constructed as a weldment. 

As assembly projects can introduce complexity, we recommend a free Design Review with one of our sheet metal experts to ensure your requirements are met. 


Gas metal arc welding (MIG) and gas tungsten arc welding (TIG) are possible on sheet metal parts at Protolabs. When designing a part requiring welding, it is best NOT to specify the exact method or type of welding unless required for function. This allows us increased flexibility when fabricating the sheet metal part, which often results in the most economical and fastest lead-time choice for the customer. 

Machined Features

Post-process machining can help produce parts with more complex geometries that are difficult to form on a press break machine or other traditional fabrication methods. While this service comes at an additional cost and lead time, possible features are: 

  • Pockets
  • Holes, cutouts or features at risk of deformation during forming
  • Flange length reduction
Tapping and Countersinking

Tapping and countersinking of holes on a sheet metal design can help integrate hardware.

  • Imperial tapped holes available between  #2 and 1/2"
  • Metric tapped holes available between M2 and M12

View our countersink chart here for thread compatibility.

Part Marking

Part marking is a cost-effective method to add part numbers, vendor-specific characters, CAGE codes, and other identifying markings to sheet metal parts. Out typical processes for part marking include: 

  • Bag & tag
  • Stencil with ink (font type is stencil with sizes between 12 pt. and 16 pt.)


Standard and Cosmetic Parts

Whether you're developing a prototype to check form, fit, or function, or you need quick-turn cosmetic parts for your next trade show, we have you covered. Use this guide to choose the best option for your project. 

  Standard Cosmetic
Description When lower cost is a greater priority than appearance Functionally cosmetic parts that make you and your parts look good to stakeholders
Use Cases Form, fit, function prototyping; internal components Testing or demonstration units, trade show parts, external components
Part Applications Internal brackets and mounts, heat shields, support structures, washers, spacers, electrical components Housings, covers, face plates, external brackets and mounts
Surface Finish Protolabs' discretion Customer specified
(grain direction, orbital sanded)
Safe Handling Yes Yes
Cost  $ $$
Quantity  1-100+ parts Best for 1-25 parts