Just wondering how you would go about making a brake light.

Not me but I bet I could using one of the cheap brake lights sold by overseas vendors for less than a dollar as a start. https://www.ebay.com/itm/Bike-Brake-Light-Mount-Tail-Rear-Bicycle-Cycling-LED-Safety-Warning-Lamp-useful/253071640656?hash=item3aec3ec850:g:v4IAAOSwr7tZfpRs It's a momentary contact switch that engages when you pull on the brake handle. Disassemble it and use it as a switch for a larger light. Not much lost if it isn't successful or you wreck it.

The idea of brake lights has been discussed here and on other bike sites. Brake lights on a vehicle work because they are bright and have a large lighted area. Over the years they have gotten bigger. Look at a vintage vehicle and you will often see a round brake light a couple inches in diameter. Not so today. In contrast, bike tail lights which could be modded to be a brake light are only a few square inches and mostly 100 lumens or less. It's been a lumen war lately among bike light manufacturers so brighter ones are showing up but do you really want to mess with an expensive tail light? Maybe the inexpensive Chinese ones yes.

there are a number of ways... the low tech way is to add a switch at the brake lever or caliper, or even on the cable.

A step up in technology is to use a pendulum to activate a switch, or for a few bucks more, add an accelerometer to measure the force of deceleration, and add a transistor to switch power to the light.

I think I've heard of a design that used GPS to measure speed, and then activated the brake light when speed decreased.

The urge to create a bike brake light seems to outnumber the urge to buy a bike brake light, though. Lots of designs have been marketed, but I can't think of the last time I've seen one used.
Still, a web search pulls up a variety of designs that might serve as inspiration...
https://newatlas.com/sigma-bicycle-brake-light/38828/
https://bikebrakelight.com/
Add a Brake Light Switch to a Bicycle Brake Lever: 6 Steps (with Pictures)
Brake Lights for Bikes: 6 Steps (with Pictures)
Check out this clever new bike brake light (video) - Cycling Weekly

Steve in Peoria

There are a few commercial lights with brake features

TL-LD710K | CATEYE

https://www.bumm.de/en/products/dyna...323-5altv.html

That is a good observation as to the fact that a small red light turning on won't attract as much attention as I want. Still,any red light is better than no light.

I am in the midst of modding an inexpensive L.E.D. flashlight into a headlight and
an L.E.D. closet light into a rear light. It will take more effort to make them than
it would to buy them but I am a retired fire alarm tech' and love to sodder stuff up.

Thanks for the info' on where to buy parts.
A relatively weatherproof micro switch is hard to make.

As suggested the brake light is more a predilection than something useful.
Unless I mount a military grade dazzler as my brake light.

A blinking red light is better than a brake light.

A brake light does not work when you are just cruising along and a car passes. A blinking light works 100% of the time.

Use a hand signal to indicate slowing or stopping.


-Tim-

Sorry Tim,I should have mentioned the brake light function would be in addition to the rear light.
The brake light may happen and it may not. Whatever I do I always try to make my own gear.
My other passion is archery. You should see the arrows I made from scratch.

At first i would calculate how huge the budget is. Commercial bicycle brakelights in mass production are 40-120€, so i guess 200$ for material and 200h of work could be possible.
Depending on the grade of existent electronic/soldering and IT/programming skills.
Role models can be theese:
Cateye Rapid X2 Kinetic (TL-LD710-K)
Litecco Twinfire
Lupine Rotlicht
See.Sense ICON+

It is fine to make things as a hobby but a brake light on a bicycle is of questionable value. I think it is almost useless and would rather have several flashing lights.

Over here, bikes aren’t allowed to use brake lights or turn indicators, to prevent them from being mistaken for mtorcycles.

Solder, man, solder.

I do, too, but only if it improves something. Or if I can't find the correct terminals in my kit of miscellaneous electrical leftovers. Or if I just feel the need to melt stuff.


And anything that can be made and shipped all the way from Chairman Mao's orphan farm straight to your door for a measly seventy-eight American pence are suspect enough when dry. Get those brake cable switches wet and I suspect they'll go full-tilt Gremlin on you.

Is there a motorcycle salvage yard anywhere near you? A road-legal bike or scooter with cable-operated brakes will have some sort of mechanically-operated brake light switch, and it should be more or less weatherproof.

Improve is nice certainly along with improvise,overcome and adapt.
This is only something I am looking at doing. Whether I do or not depends much upon
how much free time I have. I already volunteer two nights a week at an archery range.
Anything I make would be while sitting in a chair supervising shooters.
I have made my own circuit board from scratch though I don't have the
facilities any more. All a light is is a housing,wire,battery,light and switch.
All else is just specialty items needed to make that light do what you want.
I am so enthused by life that some folks think I am an expert when
all I am is interested and sometimes informed.

E-bike levers have electric switches in them, so put that to a red LED security floodlight via a battery, and your brake light needs are sorted. I have a few spare for postage cost. One lever, bit of wire, and a red battery lamp, job done in ten mins.

However, with the necessity issue, i just don't think a working brake light will translate. Nobody expects a bicycle to have a brake light, they will just see a red light. With something wrong with it.
A flashing red light is a brake/fog/tail light in one. A motorist knows there's a bike there. It's not going so fast, they're gaining on it, it's a hazard. With a brake light, it won't matter if the cyclist is braking or not, as they're still gonna be getting in the way anyway.

Yes it's easy to make a brake light. So without there even being a challenge/project in it, i really don't see the point.

I am starting not to see the point either.
A couple of our forum posters have the same perspective as you.
But often people who think alike gather together and so are for all intents and purposes one source.
Then other bikers in other forums mentioned,without being asked,that they didn't think a brake light
would make much of a difference. That's a clear confirmation.

For my own part I do see the point but that is just a single perspective.
I still see the need for,but no longer the efficacy of,a brake light.

There will be a new german StVZO approved rearlight with brakelight in 2018:
https://www.litecco.de/produkte/g-ray-detail/

I've done it - I don't know that it helps in traffic (no reason that it wouldn't), but I think it was useful when another cyclist latches on behind me. Keep it simple, a small lever switch zip-tied to the brake cable and activating against the cable stop.

Ah the zip tie,perhaps the duct tape of the biking community.
As long as it doesn't stand out then it is a great idea.

You could place the switch discreetly on or around the brake lever, but then you've got wires running down your bike. Neater to affix it to the cable, then you have just a few inches to the brake light. You wouldn't think it, but it's pretty stable and solid with a small zip-tie. Although mine is currently in a box somewhere - I didn't want to mess with it when I put a better tail-light on.

I'm thinking about rigging up a wrist band though to recognize when I'm signalling and automatically light up flashing when I do. I think that would be effective.

I was a fire alarm tech' in the construction industry and used zip ties extensively.
The only reason I object to a zip tie being used is if it looked like it didn't belong.
Hiding the locking mechanism of the tie would certainly help.
I am being kind of picky as a small zip tie in an out of the way place
certainly won't stick out,

I like your idea of the wrist band signal device.
As much as they were unsightly I was using orange backed gloves for a while.
When I hand signaled the cars behind me could certainly see.

I used a snap action switch in 1987 with the rear brakes when my bike trailer was in the planning stage. I excluded a brake light on my bike.
Center-pull calipers had the brake switch mounted on a bar on the rear forks above the caliper, activated by the equalizer bolt or a separate bolt on the cable.
Side-pull calipers had the switch attached to the lower caliper arm, activated by the upper caliper arm to illuminate the rear brake lights on my trailer.
As I am a newcomer to this site, I couldn't post photos of my trailer connections. I still have my legacy bike trailer, stored over the winter.

Well,

I made a good brake light. What was involved? 4 years and $100k plus. I think that is the reason that brake lights are not in use. They make so much sense especially now for commuters, bikers, kids and all the rest of us. You slow down. don't you want the car behind you to know so they don't plow into you.