Steel axle 2.38mm (3/32") 50mm for 1/32

The BRM-S107A axle: the mechanical base that keeps your 1/32 car well aligned

A slot car can have the most powerful motor on the market and the best-prepared tyres, but if the rear axle is not properly calibrated, all that work is meaningless. The BRM-S107A is BRM Model Cars' reference steel axle for the 1/32 scale: 2.38 mm in diameter (3/32") and 50 mm in length, manufactured with the same precision criteria that characterises the brand across all its components.

Function and performance

The function of the axle is simple to state but demanding to execute: to transmit the motor torque to the wheels without losing energy due to flexing, vibration, or play. The steel used in the S107A has a hardness that prevents deformation under load, maintaining the alignment of the wheels at all times. This has direct and measurable consequences on track behaviour:

• Reduction of vibrations at high speed, especially on long straights.
• Lower likelihood of the tyres rubbing against the bodywork in tight corners or during sudden supports.
• More uniform wear of crowns, pinions, and bearings by always working in the correct plane.

The polished surface of the axle minimises friction with the bearings, contributing to higher top speed and a longer lifespan of the rolling assembly.

Compatibility

The 3/32" (2.38 mm) diameter is the most widespread standard in the 1/32 scale. This means that the S107A is compatible with the vast majority of crowns, pinions, wheels, and bearings available on the market, both the originals from each manufacturer and third-party tuning components. If you use parts from brands like NSR, Slot.it, Scaleauto, or BRM's own spare parts, this axle will fit without the need for adaptations.

The length of 50 mm covers the usual track width of touring cars, GTs, and classic cars in 1/32 scale. If your model requires a shorter measurement, the axle can be cut to the exact length with the appropriate tools without compromising its straightness.

Assembly and preparation

The assembly is straightforward: the axle is housed in the bearings of the chassis, on which the crown and wheels are mounted. Before tightening any component, it is advisable to check the straightness of the axle by rolling it on a flat surface — any visible deviation indicates that it should not be mounted. Once installed, it is recommended to check that the lateral play is minimal and that the crown rotates in the plane perpendicular to the axle without deviations.

To get the most out of the S107A in a competition car, combine it with low-friction bearings and a well-toothed and centred crown. The axle does not require additional treatments, but a light application of slot-specific lubricant at the contact points with the bearings extends its lifespan.

Common mistakes

• Reusing a bent axle: although it may seem almost straight, an axle with minimal curvature generates perceptible vibration. The S107A is an affordable spare part; it is not worth taking that risk.
• Over-tightening the crown or wheels: this can locally deform the axle or make disassembly difficult. Use just the right amount of force.
• Not checking the length before cutting: always measure the actual track width of the model before shortening the axle. Once cut, there is no going back.

Frequently asked questions

Is this axle compatible with crowns and wheels from other brands besides BRM?

Yes. By using the standard 3/32" (2.38 mm) diameter, it is compatible with crowns, pinions, and wheels from the vast majority of spare parts manufacturers for 1/32, including NSR, Slot.it, Scaleauto, and others.

Can I cut the axle to a shorter length if my car requires it?

Yes. The S107A can be cut with the appropriate cutting tools. It is important to deburr the cut end well and check that there are no burrs that could hinder the mounting of the wheel.

How do I know if my current axle needs replacing?

Roll the axle on a flat and smooth surface: if it describes a wobbling motion or you see one end lifting, it is bent and should be replaced. You may also notice it on track as a constant vibration at high speed that does not disappear when balancing the tyres.

Is this axle suitable for 1/24 scale?

The 3/32" diameter is also used in some 1/24 models, but the 50 mm length may not be sufficient for that scale. Check the specifications of the specific chassis before acquiring it for 1/24 applications.

Does it require any special treatment or lubrication?

No prior treatment is required. A small amount of slot-specific lubricant at the contact points with the bearings is sufficient to optimise its performance and prolong its lifespan.

The BRM-S107A is a calibrated steel axle for 1/32 scale slot cars, featuring the standard 3/32" (2.38 mm) diameter and a 50 mm length. Compatible with the vast majority of crowns, pinions, wheels, and bearings on the market, it ensures straight, vibration-free power transmission. An essential spare part for club racing preparation and everyday maintenance of BRM and other 1/32 slot car models.