Learn / Engineering
Every detail.
Built for the ride.
Behind every component is a series of engineering decisions. The shape. The material. The way it is made. And the way it can be maintained.
D3A / Engineering, inside and out.
01 / From the workshop
See the work
behind the component.
Workholding, cutting tools and the people behind them. This short film brings PEMBREE’s machining and CAD work into focus, showing the process that gives a component its form.
This is where a drawing becomes something you can hold. Where a profile becomes a platform. And where engineering becomes part of the ride.
From the PEMBREE factory archive / 2022.
02 / Design into metal
Precision starts
before the first cut.
A component has to work as a design, as a manufactured part and as an assembly. Those decisions belong together.
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01 / MODEL
Give the idea a physical form.
PEMBREE’s development story begins with sketches, then 3D models in Autodesk Fusion. Printed prototypes help assess form and fit before the design is refined for the tools that will machine it. Features such as slots and chamfers are considered as part of that transition.
Inside our design workflow / Autodesk, 2021 ↗ -
02 / MACHINE
Control how the metal is removed.
CNC machining turns a digital model into a sequence of controlled cuts. In Autodesk’s 2022 account of PEMBREE’s production, Haas and Brother machining centres supported increasingly complex parts, including five-axis work. Tool access and machining strategy shape how the finished surfaces are produced.
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03 / ALIGN
Keep each operation connected.
Moving a part between machining operations introduces a new setup. PEMBREE has used on-machine probing with Fusion’s Part Alignment to measure the part’s position and adjust the machining strategy. It is a practical way to reduce misalignment and the risk of scrapping a part.
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04 / REFINE
Make the finish part of the process.
For a stem profiling operation, PEMBREE used a five-axis swarf toolpath: cutting with the side of the tool. Autodesk reported a reduction from five minutes to 30 seconds for that operation, alongside an improved surface finish. A small detail, backed by a considered process.
On the factory floor
From raw material
to the finished component.
Follow the work through nine short films from PEMBREE’s workshop and assembly archive. Each captures a different part of the process.
01 / Prepare
The shape before the first cut.
Stem blanks, ready for machining.
These recycled-aluminium blocks are the starting material for the stem. They still have a simple rectangular form: the clamp openings, contours and fastener features have yet to emerge. Securely holding each blank gives the cutting tool a stable starting point.
Original PEMBREE post ↗The D3A starts with a profile.
The D3A uses an extruded aluminium starting profile. Extrusion forms a continuous cross-section, which is cut into individual blanks. You can see that repeated shape in the pieces waiting here. CNC machining then develops the pedal’s detailed body geometry and contact surfaces.
Original PEMBREE post ↗From block to recognisable stem.
This before-and-after view shows how much changes during the first machining stage. Compare the rectangular blanks with the shaped GCS bodies that follow. Material has been removed around the features that remain; further operations complete the part before it becomes an assembly.
Original PEMBREE post ↗02 / Machine
Watch the drawing become metal.
Hold the part. Control the cut.
A blank is secured in the machine before the cutter begins its programmed movements. The fixture holds the material in position while the tool removes it in controlled passes. The flowing coolant supports the cutting process and helps carry the chips away from the tool.
Original PEMBREE post ↗A closer look at D3A machining.
Watch the relationship between the cutting tool and the fixed workpiece as the machine follows its programme. The curls of aluminium around the fixture are swarf: material removed to create the part. Tool movement, secure workholding and chip clearance all contribute to a repeatable machining process.
Original PEMBREE post ↗Follow a longer cutting sequence.
This longer D3A development clip gives a clearer view of successive tool movements and the changing position of the workpiece. CNC machining builds the required shape through a sequence of operations. PEMBREE shared this footage while the pedal was progressing towards trail and laboratory validation.
Original PEMBREE post ↗03 / Finish & assemble
Beyond the CNC machine.
Rumbling prepares the surface.
The pedal bodies move through finishing media in the rumbling machine. This process removes tiny burrs left after machining and prepares the aluminium surface for anodising. It is a finishing stage: the main pedal geometry has already been created by the cutting tools.
Original PEMBREE post ↗A controlled assembly operation.
A D3A body is located in a dedicated fixture beneath the assembly equipment. The fixture supports and positions the part so the operation can be repeated consistently. This is a glimpse of PEMBREE’s assembly line in France, where the separate components are brought together into a working pedal.
Original PEMBREE post ↗From finished bodies to boxed pedals.
The clip moves from rows of finished D3A bodies to pedals in their packaging. Between those stages, the bodies become complete assemblies with their spindles, bearings, seals and traction pins. The finished product brings the machining, surface finishing and assembly work together.
Original PEMBREE post ↗03 / Engineered as an assembly
The connection
is the component.
A stem works through its interfaces: the body, faceplates, handlebar and fasteners. The GCS uses a broad clamp, stainless-steel M6 bolts with washers, and machined alignment references. Each detail has a role in holding the cockpit together and making setup clear.
Watch the GCS animation to see those separate parts become one assembly.
04 / Purpose in every part
Look inside.
Understand the difference.
The D3A brings a machined platform, a forged spindle and replaceable internal parts together in one pedal. The exploded animation makes that construction visible.
A shaped contact point.
The double-concave body is CNC-machined from custom-extruded recycled aluminium. Its profile supports the shoe, with 12 M4 traction pins on each side.
Protection where it matters.
A forged chromoly spindle runs in sealed bearings. The recessed end cap reduces its exposure to rock strikes.
Access for the next service.
Dual-access pins can be reached from either side. Replacement pins, bearings, seals, spindles and end caps help keep the pedal in service.
Independent laboratory validation
Tested for
gravity.
The GCS handlebar and stem have passed EFBE TRI-TEST® GR testing. That gives the design independent laboratory validation alongside its intended use in demanding gravity riding.
Testing is one part of the complete product story. Correct installation, inspection and maintenance remain part of keeping a component working as intended.
Read the GCS testing information →Engineering beyond manufacture
Build it well.
Keep it riding.
The next ride matters as much as the first.
Responsibility is also a design decision: choosing materials, making service parts accessible and supporting repair. PEMBREE’s approach brings performance, durability and ownership into the same conversation.
Our current D3A pedals and GCS stems are made in the United Kingdom and assembled in France. Their engineering story continues through setup, riding and maintenance.
Explore the engineering
