I have pointed it out before. Perfection is not achieved when there is nothing more to add – but rather when there is nothing more to remove. Seen through that lens, John B Lydiards 2020 patent for a shaving brush with interchangeable bristles is far from perfect.

The idea is simple enough. Different shaving brush knots have different qualities, and people prefer different knots. Some likes the softness of badger, some prefer a scritchy boar. Me, I like a good horse. But to get back on track, let us see what John had to say in the patent text

A problem with shaving brushes is that the bristles are permanently attached by glue or other adhesive, thus making it impossible to change to different bristles according to the desires of the user, thereby requiring one to purchase multiple brushes for different bristles. Thus, a need exists for a shaving brush which will allow a user to change to different types of bristles, such as without limitation, synthetic, boar, badger, or bristle knot, by cartridgizing the shaving brush knot.

Needlessly to say, I disagree with the perceived need. And I have a reasonable modest brush collection, compared to some shavers.

So, how were John planning to get around using an adhesive to secure the knot in the handle? By replacing it with arrangement of threads, levers, push-rods, bell-cranks and a clamp. Easy-peasy.

The pictures do more justice to the gadgetry of the invention than mere words.

From my understanding of how John envisioned his shaving brush with interchangeable bristles working, this would be the order of operations:

• Loosen the tension ring (#1 on the drawing) and screw it all the way down.
• Push on the spring loaded release button (#4) so the two halves of the fastening cuffs (#9) swings up and to the side.
• Pick up the old knot (#32) from the floor, sink, or wherever it fell.
• Insert a new knot (still #32) with an adaption hoop (#12) into the fastening cuffs (#9) and push the cuffs together.
• Screw the tension ring (#1) all the way up around the fastening cuff (#9) and tighten it.

Now, compare this to how I pick a new shaving brush knot:

• Reach out, grasp the brush I want.

And even if it wasn’t pointlessly complicated, John seems to have forgotten one minor thing: Storing a shaving brush knot takes up about as much space as storing a whole shaving brush! So there is added complexity with no benefit that I can see.

I mean, I can see part of what he was going for. The words cartridgizing the shaving brush knot gives the game away. I think John wanted to set up a walled garden, where people who bought his handle would have to turn to him for shaving knots.

While it is only two years since John patented his brush with interchangeable bristles, I just can not see it being successful in the marked – unless the target audience is people with more money than common sense.

Which is, admittedly, a large market.

You can read the full patent for the shaving brush with interchangeable bristles over at Google Patents.