Unsung heroes of the factory floor

Jigs and fixtures – unsung heroes of the factory floor – enable the consistency and repeatability needed to achieve mass production, guiding people and robots through precise manufacturing and assembly operations.

Traditionally, most jigs and fixtures are machined from metal. These tools are heavy, expensive, require long lead times to iterate a final design, and are often made by third-party suppliers. Once the die is cast, these tools are difficult and expensive to modify.

Functionality comes first; user ergonomics are not usually a priority. A lost or damaged tool or any changes in product design to next year’s model can result in significant delays and retooling expenses.

Today, additive manufacturing (AM) offers several advantages to overcome challenges of traditional tool creation processes. Advances in AM technology and development of chemical- and temperature-resistant polymers capable of replacing metal have opened the door to a growing number of production line applications for 3D printed (3DP) jigs and fixtures. Here are a few examples.

3DP production tools

Jigs and fixtures used on the production line aid in component assembly or act as guides for precise placement or joining of parts.

• Assembly jigs ease labor-intensive tasks by holding a part in a specific orientation, making it easier for a technician to work on the part, connect it to a subassembly, or add a fastener, improving speed, consistency
• Protection jigs, such as boots and covers used to shield sensitive areas of printed circuit boards during chemical coating or bathing processes
• Alignment jigs, drill guides ensure precise tool positioning when connecting parts, milling holes within prescribed tolerances without bit drifting
• Soft vice grip inserts for clamping parts with unique geometries in exact position, no shift
• Bonding jigs hold a part’s exact position while it’s being connected to another part with liquid adhesive; the high rate of replacement due to solidified adhesive collecting on the jig during curing makes bonding jigs an excellent candidate for AM
• Robotic grippers – end-of-arm tools/end effectors – pick up, hold, position parts for machining or assembly tasks; 3DP grippers are lighter, require less robust arms to hold jig in place, less power to operate
• Part cradles – fixtures or nests hold a part in position while another machine works on it; often have notches, pins in exact positions to ensure part is oriented, properly locked in fixture
• Labeling and masking templates ensure imprint or label is repeatedly placed at the exact location; AM excels at producing low-impact, non-marring templates customized to a specific shape

3DP quality control, inspection tools

Jigs and fixtures used on the production line aid in component assembly or act as guides for precise placement or joining of parts.

• Go/No-Go gages optimize product quality, reduce costs, speed production by helping validate parts, subassemblies for use in the final product; AM quickly, easily, affordably reprints worn out gages
• Disassembly jigs necessary to examine a product that failed inspection or requires internal access for refurbishment or repair; holds a part in place and disengages multiple snap fit or spring-loaded connectors that must be released simultaneously to access the interior without damaging exterior casing

3DP ESD-safe tools

In electronics manufacturing, any tool contacting an electronic component must be grounded and offer surface resistance sufficient to prevent static electricity buildup and resulting electrostatic discharge (ESD) events that can fry sensitive electronics. Rather than milling them from blocks of expensive ESD-safe plastics such as Delrin, manufacturers can 3DP their own ESD-safe screwdrivers, pliers, tweezers, part trays, etc. in-house at low cost.

3DP proof of concept tools, parts

Not every jig and fixture can be 3DP; many will require the strength of metal to meet the rigors of long-term mass production. However, 3DP jigs and fixtures can serve as proxies for the final tools for test fit, ergonomics, and performance while the assembly line is being built or retooled. Surrogate parts can be printed in the shape of a final part to validate the production line and not waste actual parts during pre-production testing.

3DP packaging and holding fixtures

Manufacturers can now 3DP customized inserts in the exact shapes needed to package and transport odd-shaped products without incurring damage.

New efficiencies

The cost and time of producing jigs and fixtures through traditional means often yield tools aren’t optimized for the job at hand. They may be bulky, heavy, or result in user fatigue and injury.

3DP jigs and fixtures can reduce lead times, save money, and deliver increased control over functionality and ergonomics. Complex shapes are not an issue as with conventional molds; AM is great for applications such as soft vise inserts with unique features like teeth needed at precise positions to secure a custom part. These can be iterated quickly and at low cost with minute changes to the CAD file and reprinted until the exact shape is achieved.

Lost, worn out, or broken tools can be 3DP in any quantity on demand for just the cost of filament. Should an engineer or assembly line worker have an idea to improve upon a tool’s current form or function, AM offers a cost-effective platform to experiment and design new solutions for the health, safety, and improved productivity of users – and most likely much lighter than the weight of the original tool.

While AM doesn’t replace jigs and fixtures requiring the highest levels of strength and durability, if a product is expected to change frequently, if a tool is expected to have a shorter shelf life, or if the volume can’t justify the cost of producing conventional tools, 3DP offers a viable alternative to produce needed jigs and fixtures at a fraction of the time and cost of traditional methods. AM technology and engineering-grade materials deliver the speed, strength, and scale to support the in-house jig and fixture production required by manufacturers to minimize downtime on the production floor.

About the author: Blake Teipel Ph.D. is CEO of Essentium.

Essentium Inc.
https://essentium.com