Serious hot rodders love vintage speed and high-performance equipment. When you look at the “wish lists” of nostalgia rodders, you’ll find exotic parts like real “block letter” Edelbrock finned heads, Harman and Collins magnetos, Auburn dash panels, and arguably the most elusive item of all, the legendary Kinmont Safe Stop Disc Brake.
What were Kinmont brakes?
Old car aficionados may recall Kinmonts as an interesting side note on two notorious, postwar, would-be auto manufacturers: the flamboyant Preston Tucker and the enigmatic Gary Davis, originators and self-promoters respectively, of the ill-fated ’48 Tucker Torpedo and the hapless Davis three-wheeler of the same era. Tucker’s short-lived enterprise (only 51 cars were produced) ended up in the courts, but after an ill-deserved trial for stock fraud, he was acquitted of any wrongdoing. Davis, also indicted for fraud, after producing 17 prototypes (additional cars were built later from stockpiled parts), served 18 months at a misdemeanor farm in Castaic, California.
Both men’s efforts had something else in common, besides trials and tribulations. Tucker and Davis allegedly wanted their radical new models to be equipped with the best stoppers of the day, so they turned to a small manufacturing company in Los Angeles for a rather unusual disc brake that did not rely on a rotor/caliper assembly to function effectively. Attributed to an inventor, Joseph M. Milan, and originally called the Milan brake, they became better known by the name of the company that tried and failed to make them a success, as Kinmont Safe Stop Disc Brakes.
Period articles on both the late ’40s-era Tucker and Davis refer to disc brakes, and vintage cutaway drawings of both Tucker and Davis cars clearly show the distinctive Milan/Kinmont finned backing plates. We know that prototypes of both makes experimented with Kinmonts, but neither car employed them in its limited production models, due to their relatively high cost (versus conventional hydraulics) and the lack of time the engineers in both companies had for extended in-service testing.
Years ago, the late-Gary Davis told Special-Interest Autos’ Mike Lamm that he’d tested Kinmonts, but “didn’t have enough money to get one (tooled) in aluminum. So I used cast iron, and this made the load too heavy below the center of gravity.
We’ve learned even more, and since I’ve been running a set of Kinmonts for 11 years on all four wheels of my ’32 Ford roadster, I’m in the unique position to bring you up to date.
Joseph M. Milan, an exotic car mechanic, recorded the first of his 10 disc brake patents back in 1936. Allegedly, the basic design was patterned after a clutch-like brake assembly used on mobile World War I German heavy artillery pieces. Relentless researcher Fitzhugh traced the first competition use of the Milan-style brake to a 1941 Indy 500 race car owned by Joe Lencki and driven that year by Emil Andres.
This first racing Milan brake was made entirely of aluminum. It consisted of a cast aluminum cover (more popularly called a “hat”), with 12 forward-facing vents that were angled to scoop in cooling air, and direct it across a 360-degree continuous ring, circular flat braking surface. The braking material, a soft asbestos compound with brass rivets, made by the Raybestos Corporation, was attached in three places to the brake cover (also known as a driving member), which rotated with the wheel.
The friction material was squeezed between a stationary backing plate and a pressure plate that resembled a conventional automotive clutch. Four simple spring straps return the plate to the “at rest” position. The simple adjustment consisted of just two nuts that regulated the clearance between the pressure plate and the backing plate, which was distinctively and efficiently finned to dissipate heat buildup. Unfortunately, Andres’ Kennedy Tank Special crashed on Lap Five in the 1941 Indy 500, and finished an ignominious 30th. But alert “railbirds” like Preston Tucker saw these newfangled brakes and would consider them seriously once hostilities ceased and racing began again five years later.
Fast forward to the Kinmont Manufacturing Company in Maywood, a suburb of Los Angeles. Kinmont produced hydraulic dredging equipment. During World War II they manufactured a torpedo launching platform and built a prototype U.S. Army tank. Before the war, Milan, along with a group of investors, spent a great deal of money prototyping his novel brake design. He had been looking for a company to manufacture and market the brakes in volume.
Coincidentally, Bill and Ralph Kinmont, heirs of the Kinmont Company’s founding brothers, were seeking postwar manufacturing opportunities. Bill Kinmont, a racing enthusiast, met Joseph Milan some time earlier, and had seen his brake design. Hoping to develop a practical brake for the road, the Kinmonts retained Milan as a consultant, and began manufacturing what would soon become known as Kinmont disc brakes.