Overkill Racing Brings Wild Ideas to Life

Building a monster truck involves significant systems-integration challenges. The tubular chassis, suspension, engine, plumbing, sheet metal, tires, and other components must be spatially compatible within limited space. In addition, the suspension must move without causing collisions among tires or components.

For Overkill Racing and Chassis owner Joel Buschmann, that challenge began as a diversion followed by a sharp departure from his academic plans. While pursuing a graduate degree in cellular and molecular biochemistry, Buschmann decided to build a mini-monster truck. He transformed a 1968 Chevrolet Suburban, mounted it on 54-inch tires, and brought it to the 2011 SEMA Show. Attendees had difficulty believing the vehicle had been built by a 24-year-old. That project grew into a custom fabrication business specializing in wildly imaginative vehicle designs. 

Outgrowing a Tube-Only Workflow

Overkill’s early work focused on chassis fabrication and tube structures. Buschmann initially used software suited to tube design. That worked until projects began demanding more than bent and joined structural members. According to Buschmann, “It's great for some of the tube work stuff, but then all of a sudden you gotta start building sheet metal components or dynamic assemblies and, that's where it just falls off the cliff.”

A monster truck cannot be developed from isolated parts. The frame establishes the foundation, but the suspension, engine, plumbing, sheet metal, and other components must be designed around one another. Buschmann needed to see the complete vehicle and determine how those systems would behave together before he committed his design to metal.

Bringing the Entire Build Together

Buschmann began using SOLIDWORKS® Design around 2014. The 3D CAD software supports core capabilities, including parts, assemblies, drawings, sheet metal, and framing. That combination made it possible for Overkill to develop sheet metal parts, moving components, and tube structures within a complete vehicle assembly.

“Once I jumped into SOLIDWORKS, I never looked back. It gave me the ability to design sheet metal parts, create moving components, add all the tube work, and bring everything together in one complete assembly.” Buschmann notes.

Buschmann approaches a monster truck much like building a house. The chassis is the foundation. The suspension follows. Then the engine, plumbing, and remaining components are added. This sequence enables him to systematically build up the vehicle while accounting for the space each system requires.

Movement is essential to the digital model. 

Overkill models its assemblies in SOLIDWORKS so the suspension can move through its full range of travel. Buschmann can position the suspension to represent conditions such as a hard landing, then check tire clearances and identify potential contact between components.

Doing the Hard Work Before Fabrication

Overkill pushes projects well beyond a rough concept before manufacturing begins. “We try to model everything to 90% completion before we start the manufacturing phase,” Buschmann explains.

That high level of digital completion reduces the number of fit and motion questions that must be resolved in the shop because the team determines how the major components will fit and move together before fabrication starts. Buschmann estimates that digital work accounts for most of the overall build: “About 80 percent of the build is done on a laptop. That makes the other 20 percent, the manufacturing, so much more efficient.”

The benefit is not simply more detail in the digital model. It’s a practical check on whether the design can come together as intended and be assembled as is. Developing a vehicle in 3D takes additional effort early on, but it makes physical assembly easier and enables a check of the concept before parts meet on the shop floor.

Taking Childhood Ideas All the Way to Metal

For Buschmann, digital design connects an ambitious idea with the discipline required to fabricate it. With SOLIDWORKS Design he is able to develop the chassis as a foundation, add the vehicle’s systems, examine suspension movement, and resolve spatial relationships before manufacturing.

The technical process still nourishes a deeply personal goal. “My favorite thing to build has to be monster trucks. The five-year-old version of me would be so pumped to see what the 38-year-old version of me is doing now,” he concludes.