By using Markforged 3D printer, engineers at Stanley Black & Decker saved thousands of dollars per year while replicating the quality and reliability of machined parts.

Stanley Black & Decker, an S&P 500 company, is a diversified global provider of hand tools, power tools and related accessories, electronic security solutions, healthcare solutions, engineered fastening systems, and more. Its Stanley Infrastructure division is searching for ways to manufacture low-volume, complex parts in a cost-efficient manner.

By leveraging Markforged’s Metal X additive manufacturing technology, the Infrastructure team expects to slash capital costs on two different parts: an actuator housing for the PD45 hydraulic post driver, and a wheel shaft for the PG10 grofile ‘Frog’ grinder. Engineers at Stanley Infrastructure rigorously tested the performance, durability, and lifecycle of each of the two parts and approved them for use as production parts for a fraction of the cost.

The Stanley PD 45

The Stanley PD 45 is a high efficiency hydraulic post hole driver. To actuate the hydraulic driving mechanism, the device uses a group of ball bearings to transfer the trigger pull force into the hydraulic actuator. The actuator housing holds these bearings in series to transfer pull force around a bend. Each housing is tested every time the operator pulls the trigger.

The original actuator housing consisted of four parts: a cast and machined main housing; a laser cut cover plate; and two bolts to fasten the housing assembly together. Stanley Infrastructure engineers redesigned the part to print on the Metal X. Instead of a four-part assembly, the redesigned part prints in one piece without supports.

Stanley Infrastructure tested three identical parts printed on the Metal X. These parts proved durable through tens of thousands of cycles and strong enough to handle significant compressive load while also being 53% lighter. By replacing its current manufacturing work flow with the Metal X, Stanley Infrastructure saves between 34% and 48% on manufacturing costs and reduces part lead time by 69%.

While these are significant savings, the Metal X is even more effective in single part manufacturing. Stanley Infrastructure often produces single replacement parts for devices in the field. Because its existing process only produces parts in batches, printing single parts with the Metal X is 12.5 times cheaper and 20 times faster than casting and machining. The Metal X further undercuts this process by being a pay-per-part machine instead of a pay-per-batch machine.

According to one Stanley Infrastructure engineer: “It is very feasible to leverage the Metal X platform in additively manufacturing the discussed actuator housing with very minimal capital and time investment.”

The Stanley PG10

The Stanley PG10 Profile Grinder is used to perform surface-finishing operations on railroad tracks. The wheel shaft holds adjustable guide wheels onto the body of the grinder. Each part is loaded with the full weight of the grinder and is subject to shock loads. The geometry of this part, with its large flange and long aspect ratio, means that it’s volumetrically inefficient and expensive to manufacture.

Stanley Infrastructure used to machine these parts out of a single block of steel. Because of the size of the flange and the length of the shaft, they wasted around 90% of the stock material in each part. With the help of Markforged, Stanley Infrastructure engineers redesigned the wheel shaft to be a three-part assembly. By purchasing an off-the-shelf shaft and key, they were able to easily print the flange on the Metal X.

Stanley Infrastructure tested three samples with drop tests. The parts passed durability testing (many small drops of the grinder onto a steel work surface) and abuse testing (extreme shock testing involving drops of the same grinder from high heights, such as a truck bed) while being 20% lighter than the original part.

By replacing the wheel shaft with Markforged’s printed flange and shaft assembly, Stanley Infrastructure cut its production lead time in half and saved between one-quarter and half of its production budget for full-volume manufacturing. However, since this part is a high-wear component and the production volume for this grinder is low, the most lucrative use of the Metal X comes from the savings it delivers in one-off manufacturing. Replacing the inefficient-to-machine original part with a Metal X print yields cost and time savings amounting to 25 and 50 times respectively on a single part manufacturing basis.

Parts printed on the Metal X have the potential to save industrial customers significant capital if utilised correctly. By designing intelligently for these machines, minimising print time, and using off-the-shelf parts when possible, it’s possible to produce high-quality parts much more cost effectively than subtractive manufacturing.