Michael Perry Résumé

Work/03

Stirling Engine

Modeled in SolidWorks, machined and assembled.

I modeled a Stirling engine in SolidWorks from supplied engineering drawings, performed tolerance analysis, machined the parts in the university machine shop, and assembled a working engine.

Status
Completed, working engine
When
Spring 2026
Tools
SolidWorks, manual mill and lathe
Scope
Part modeling, assembly, tolerance analysis, bill of materials, machining, assembly
Exploded isometric assembly drawing of the Stirling engine: base plate, frame, flywheel, crank, displacer and power cylinders, fasteners, with balloon callouts numbered up to 39
Exploded assembly drawing from my SolidWorks model. Balloon callouts key each part to the bill of materials. Scroll sideways to see the whole sheet.

01The finished engine

The finished engine

This is the finished engine running. The base and frame are aluminum, and the flywheel and cylinder are brass.

A small Stirling engine produces very little power, so it only runs when friction is low and the moving parts are well aligned. Getting it to run meant the model, the fits and the machining all had to be right.

02Process

Design and build process

  1. Read the drawings

    I started from the supplied engineering drawings and specifications and worked out how each part functions in the assembly.

  2. Model the parts

    I modeled each component in SolidWorks and mated them into a full assembly to check fit and motion.

  3. Tolerance analysis

    I checked the fits between mating parts so that sliding fits would slide and press fits would hold.

  4. Bill of materials

    I put together a bill of materials covering stock, machined parts and hardware, keyed to the exploded drawing.

  5. Machining

    I machined the components in the university machine shop on the manual mill and lathe.

  6. Assembly

    I assembled the engine, found what was binding or leaking, and corrected it until the engine ran.

03What I learned

What I learned from the build

Working from engineering drawings taught me to read a drawing for what each part does in the assembly. Modeling the parts and the assembly in SolidWorks let me check fits and motion before I cut anything.

The tolerance analysis mattered most once I was in the shop, because the sliding fits had to slide and the press fits had to hold. Machining parts from my own model also showed me how CAD decisions affect manufacturing: every dimension I had chosen was one I then had to hold on the mill or the lathe. Assembly was the last check, and it meant finding and fixing the problems that kept the engine from running smoothly.

04How it works

How a Stirling engine works

A Stirling engine runs on a temperature difference. A fixed amount of gas is sealed inside, and a displacer moves that gas back and forth between a hot end and a cold end, which makes its pressure rise and fall. A power piston, a quarter turn behind the displacer, is pushed out while the pressure is high and returns while it is low. The difference is the work that keeps the flywheel turning.

This interactive model shows the cycle. Change the temperature of the hot end to see how the linkage and the pressure-volume loop respond.

Illustrative thermodynamic and kinematic model. Not measured performance data from the physical engine.