Design cost out by increasing part complexity.

Tyler Reid, Manufacturing Application Manager, GoEngineer

Engineers are normally introduced to the concept of design for manufacture (DFM) while in school. But the reality is that the majority of engineers don’t actually learn how to design for manufacture until they are on the job.

And this can be a hard lesson.

The CAD model is only the first step in the long journey from concept to physical part. DFM rules have been developed over the years to help engineers build parts that can be efficiently created. Designing features that fit standard-sized cutters and using off-the-shelf shapes and components are basic rules to keep costs down.

But the sobering reality is that no matter how perfectly manufacturing steps are followed cost is always being designed into the part—every pocket cut, every hole drilled comes with a price in material waste, cutter wear, and machine time.

Additive manufacturing, however, turns this scenario completely around by encouraging part complexity: pockets and holes suddenly become time-savers!

With 3D printing, engineers can design cost out of a part when adding features while eliminating extraneous material and additional assembly steps. Ironically, increased part complexity in an additive manufacturing environment has naturally progressed into bill-of-material (BOM) simplification.

Many traditional aerospace and defense parts are actually assemblies of several simpler parts brought together to form the final product. The individual pieces can be manufactured for an affordable price, but the additional assembly steps are laborious and can introduce reliability concerns.

This is potentially expensive on many levels.

Using adhesives, pins, nuts, bolts, screws, and rivets to fasten parts bloats the BOM and makes the engineer’s job exponentially more difficult (spec’ing hardware and finite element analysis of fasteners is a science of its own). Welding doesn’t come any easier either with concerns about heat affected zones (HAZ), part porosity, internal stresses, and required post-processing.

The ability to replace more than 20 components within a BOM with a single part, while simultaneously eliminating assembly, is an additive manufacturing advantage that both Airbus and the European Space Agency (ESA) have publicly celebrated for production and test parts.

Direct benefits in both above examples included fewer parts and elimination of welding, but other acknowledged benefits were reduced weight, reduced warehouse space and inventory cost, decreased waste and overall energy used, and the ability to continuously revise the part if needed.

Traditional approaches to design will need to be re-imagined as additive manufacturing becomes more and more a part of the typical process for producing world class products where maximizing cost, quality, and time-to-market is paramount.

 GoEngineer
www.goengineer.com

Guest blogger Tyler Reid is a CAD, CAM, and 3D printing specialist. His early interest in machines and machine tools led him to study Mechanical Engineering at the University of Utah. Before graduating with his Bachelors of Science in 2009, he began his professional career at BD Medical where he was involved in developing, testing, and manufacturing a new drug infusion technology. Now an Applications Engineer focused on 3D printing, Tyler leans on his technical background and experience to present and speak on industrial additive manufacturing applications.