Coffee Beater Enclosure: Designing a Hand-Held Beater from CAD to Prototype

The product

The Coffee Beater is a hand-held beater for frothing milk and mixing coffee: a stainless coil whisk on a thin steel shaft, driven from a compact green housing with a red push button and a USB-C port at one end. I designed the housing: the two enclosure sections, the nose cone that the shaft leaves through, and the spacer that holds the inside together. This case study follows it from CAD to a built prototype.

What the design shows

Read from the model, the renders and the prototype:

• One control. A single push button sits on the end of the handle, and nothing else sits on the grip.
• USB-C on the button end. The port is on a flat beside the button, so the cable plugs in at the same end the user switches the beater on.
• A faceted body. The housing has flat faces and chamfered corners instead of a round profile.
• A two-section body. A visible seam splits the housing into a long main section and a short button-end section.
• A cone-shaped nose. The steel shaft leaves the housing through the tip of a separate cone-shaped piece.

Every component

The CAD package holds four parts: the Upper and Lower Enclosure, the Internal Spacer and the Coupler. The whisk, shaft, button and USB-C connector are hardware outside the CAD package, shown here because they decide the openings in the housing. The numbered figure labels the two enclosure parts by their position on the product.

The modelled parts

Both are single solids. The coupler is a body of revolution: a bored stub on a cone. The internal spacer is a ring with six radial ribs, so it has about five times the faces of the coupler.

Wireframe views

The assembled views are edge extractions from the studio render, so they show the housing sections, the seam, the button, the USB-C opening, the nose cone, the shaft and the whisk. The coupler and spacer wireframes come straight from their STEP files, with hidden edges dashed.

In use

The prototype

The design was built as a green prototype. The photographs show the real unit on a desk.

Compared with the studio render, the prototype shows the same arrangement:

• The seam. The housing splits into a long main section and a short button-end section in both.
• The end face. The button and the USB-C opening sit on the end face in both.
• The nose. A cone-shaped piece sits at the other end with the steel shaft at its tip in both.

How the numbers were checked

• The two STEP files were opened with a CAD kernel to read bounding boxes, solid volumes and face counts, so every figure in this study comes from the geometry.
• The edge drawings were generated from the same STEP geometry, not redrawn by hand.
• The Upper and Lower Enclosure exist as SolidWorks part files only, so no dimensions are quoted for them here.
• The renders and photographs are the project’s own images; the callout figure is drawn over the studio render.

What this study does not claim

It does not give weights, battery, motor or performance figures: they are not in the files, and I do not quote what I cannot show. Internal parts other than the spacer are not documented here.

Links

• Design review or a product enclosure of your own? Get in touch.
• Weighing a housing for sheet metal or welding instead? See Designing Heavy Welded Structures for Manufacturability and Sheet Metal K-Factor Mathematics, with the free Welded Structure DFM Toolkit and Sheet Metal Bend Calculator.