Can I machine the adapters myself?

Yes. The design guides exist for that. Keep the critical dimensions, respect the materials and verify the assembly against SAE J328.

Can Michigan Scientific make them?

Yes. Rim and hub adapters are designed and machined for each vehicle, standard or weight-optimized, and adapters can also be rented.

Is there a guide for my transducer model?

Guides are published here for the LW12.8-50, the LW65 and the LW-2T-20K. For another model, ask for its drawing.

Designing rim and hub adapters for a wheel force transducer

The essential

The transducer bolts between a rim adapter and a hub adapter made for your vehicle. On the design guides, the dimensions in blue are critical and cannot change: they hold the transducer and carry the rated loads. Everything in black is yours to adapt. Start from the profile of the original wheel, keep the transducer as close to the wheel centerline as you can, verify the assembly against SAE J328, and send the design to Michigan Scientific: the check is free.

What is fixed and what is free?

Blue dimensions are fixed, black dimensions are free. Each design guide is a drawing of the interface between the adapter and the transducer. The blue features let the system withstand its rated loads and reproduce the mounting under which the transducer was calibrated.

Fixed, among others: the pilot diameter, the transducer bolt circle, the flange thickness, the threads.
Free: everything else. The guides show examples of permitted changes.
3D models and 2D drawings of the transducers are available for download.

How is a rim adapter designed?

From the wheel profile of the test vehicle's original wheel. If no 3D model or drawing of that wheel is available, the tire mounting profile is taken from the Tire and Rim Association or ISO standards.

Material: 6061-T6 aluminum forging, with a yield strength of at least 275 MPa (40 ksi). A forging has a consistent yield strength and hardness throughout.
Bar stock or billet is not equivalent: its heat treatment may not be consistent through the section, with a lower yield strength and hardness than published. With a weaker material, the sections have to be thicker.
Flange thickness is imposed: 16.51 mm (0.650 in) on an LW65, with M10 × 1.5 fasteners that pass completely through the flange; 12.7 mm (0.500 in) on an LW-2T-20K, with M14 × 2.0 fasteners threaded all the way through the transducer.
On an LW-2T-20K, a 16 in rim may need cutouts in the wheel drop to let the fasteners in. Below 16 in, ask Michigan Scientific.

What are the cooling cutouts for?

The cutouts in the rim adapter let air reach the brakes and take weight out of the assembly. Their size and shape are refined for each design.

Align the pattern of cutouts away from the transducer mounting holes.
On an LW-2T-20K, the number of cutouts should be a multiple of 24.

Where should the transducer sit?

As close to the rim centerline as possible. The WFT offset is the distance from the centerline of the rim to the centerline of the transducer; the smaller it is, the lower the moment load on the transducer.

Leave at least 3.8 mm (0.15 in) between the transducer or its adapters and the brake and suspension components, to prevent interference.
A telemetry system needs additional clearance; it is given on the drawing.

How is a hub adapter designed?

In 17-4 H1100 stainless steel, as Michigan Scientific machines them: it limits the brake heat conducted to the transducer. Alloy steels can be used, but they conduct more brake heat.

Material: yield strength of at least 890 MPa (130 ksi), hardness between 32 and 45 HRC.
Hub thickness: not less than 10.16 mm (0.400 in).
The guides detail a geometry that reduces the stresses and increases fatigue life. On an LW12.8-50, the corner angle stays between 115 and 145 degrees.

How is the design verified?

Michigan Scientific verifies every rim and hub adapter assembly by finite element analysis that simulates the SAE J328 wheel durability standard. Do the same with yours, to verify the load rating and the fatigue life.

SAE J328 static load rating, not to be exceeded: 1 015 kg (2 240 lb) for an LW12.8-50, 1 320 kg (2 900 lb) for an LW65, 1 815 kg (4 000 lb) for an LW-2T-20K.
For the best accuracy, the lateral stiffness of the rim adapter should match that of the adapter used to calibrate the transducer.
Michigan Scientific checks your adapter design at no cost.

How do you take mass out?

The closer the mass of the instrumented wheel is to that of the production wheel, the more representative the measured loads: an assembly that is much heavier can generate lower peak loads. The adapters are a key contributor to that mass.

Choose a transducer of the appropriate range, then weight-optimized adapters.
Lightweight rim adapter: machined from an aluminum forging, in one piece.
Lightweight hub adapter: machined from titanium instead of stainless steel.
Size the adapters on the maximum static load of the vehicle, not on the maximum capacity of the transducer: the lighter the vehicle, the more mass comes out.
The optimization service is included in the purchase of reduced-mass adapters.

How does an adapter project run?

When Michigan Scientific designs the adapters, the aim is to match the design and the weight of the original wheel as closely as possible and to reduce the WFT offset. The lead time starts when you approve the design, not when the order is received.

Information: a completed adapter checklist with photos (lug nut, lug nut seat, stamped wheel information, brakes). The checklist is mandatory, even when CAD is supplied: the two are compared to make sure the adapters fit.
Wheel CAD: a 3D model, preferably a .step file, or a 2D drawing in PDF.
Brake CAD: the rotor and the caliper only, or a swept brake profile, the volume to stay out of.
Design: the rim profile comes from the Tire and Rim Association year book; the standard features (pilots, hole patterns, flange) match the calibration conditions. FEA runs alongside to check fatigue life.
Review: you receive a .step file of the assembly and a PDF of the assembly drawing, and approve or ask for changes.
Options: powder coating of aluminum rim adapters; adapters made of alloy steel are nickel plated against corrosion.

Design guides and checklists to download

One drawing per adapter and per transducer model, with the critical dimensions in blue, and the checklists to fill in for an adapter project.

To remember

Blue dimensions are fixed, black ones are yours.
Forged 6061-T6 for the rim adapter, 17-4 H1100 stainless steel for the hub adapter.
Smallest possible offset, 3.8 mm of clearance at least.
Verify against SAE J328 and stay under the static load rating of the transducer.
Send the design: the check is free.

Updated October 2026. Values from the Michigan Scientific design guides dated 2020; the drawing of your transducer model prevails.