Magnetic brakes

magbrakeman

Hey i'm making some magnetic bike brakes for my GCSE project and would really apreciate it if you could fill out a survey for my coursework,
Thank you very much,
Henry
https://www.surveymonkey.co.uk/r/MJ5PMCX

steve_sordy

Where is the survey then?
I expected you to have posted a link here.

JBA

No link to the survey.

Putting your e-mail address on a public forum is daft thing to do as well.

figbat

Interesting idea - I wonder if these are contactless electro-magnetic type of retarders (a la lots of trucks and buses) or simply using magnets as the application force for normal friction pads?

I guess we'll never know.

billycool

Guys - give him a break.

Henry - I don't know if you mean you have a survey you need to send to us or if it is on-line. An on-line one is more likely to get a response.

The best thing to do is post a link on here to the survey. If you don't have that, you can create a free one using Survey Monkey.

https://www.surveymonkey.com/

It is best to remove your email address as you may end up getting lots of spam email.

magbrakeman

https://www.surveymonkey.co.uk/r/MJ5PMCX
Here it it soz

CitizenLee

Remove your email address mate, otherwise you'll find your inbox filled with emails about Russian brides, cheap Rolex watches and methods to overcome erectile dysfunction.... unless any of those interest you of course :P

Anyway, survey done

cooldad

Um?

Spelling and grammar - 5/10 - better than some...

Questions - Rather vague - 4/10 - how can someone know how much they want something with no idea of what it is?

ps. This is Alot



http://hyperboleandahalf.blogspot.com/2 ... thing.html

cougie

Done.

I don't know what magnetic brakes are but they sound cool.

shirley_basso

You spelt beginners incorrectly.

The survey is a bit wierd. Asks generic age and occupation, then 3 questions about whether people want maintenance free, silent, non-overheating brakes (yes to all 3) then asks if you want magnetic brakes. End.

What are magnetic brakes?

Gary30

I realise this is a GCSE project (good luck!) but the old adage stands that there is no such thing as a free lunch.

Heat is still generated as the kinetic energy has to go somewhere.

If you're looking at regenerative braking, then you have to factor in the extra weight of the equipment and whether it would be worth the trade off.

Interesting topic though.

kajjal

Wouldn’t magnetic brakes generate some kind of electrical field ?

Especially if using them going from 30mph to a rapid stop.

steve_sordy

Without knowing for sure what you mean by magnetic brakes, I don't want them to weigh any more than what I have now, nor cost too many times what my current brakes cost now. Not too sure that I want anything electrical in my brake system when I ride through water and so forth.

By magnetic, do you mean friction brakes but applied magnetically onto a brake disc? Or are we talking about using some sort of field effect to generate braking? In the latter what is the magnet acting against, how big does it have to be for the same performance (back to weight and cost again).

I have in my mind the Eclipse locking magnets that I used to use years ago. These were in the bases of dial gauges. You just pushed a button on the side and the base was rigidly clamped to whatever ferrous metal it was sat on. My assumption is that it was several magnets placed in contact with each other with poles aligned so that they counteracted each other. Pushing the button brought them into a different alignment that did not cancel each other out. The buttons produced an on or off effect, but I guess with say a lever instead of a push button, then the braking could be controlled. But to get a strong enough effect from natural magnets (rather than an electro magnet), they were heavy! :shock:

02gf74

cooldad wrote:

I expect his first job will include 'Would you like fries with that?'

.
.that's after promotion.
. Yet another post by a school child requesting some random survey never to post again.... Gggrrrrrr....
.
.strangely I find myself attracted to the idea of magnetic brakes.

cougie

Most of us were young once.

I prefer these questions to the ones from most of the grownups.

Good luck with it magnetic boy.

magbrakeman

Hey just want to say thanks for all the helpful replies and advice, this was all very last minute and I appreciate the patience of everyone that takes it. As for all the less helpful people making comments on my age I'm sorry I'm trying to do something with my life, I hope you enjoy bullying children on the internet.
Henry

magbrakeman

Shirley Basso wrote:

You spelt beginners incorrectly.

The survey is a bit wierd. Asks generic age and occupation, then 3 questions about whether people want maintenance free, silent, non-overheating brakes (yes to all 3) then asks if you want magnetic brakes. End.

What are magnetic brakes?

Sorry about the bad survey I only get 10 questions and this was all quite last minute, as for your question I was going for a does it sound cool angle

shirley_basso

I see what you mean but for a project, a 'does it sound cool' idea often doesn't fly with cyclists. Typically a conservative and highly nerdy bunch.

That said, I think a bit more questioning about what magnetic brakes bring over caliper brakes would be helpful so people could appreciate how they provide an advantage.

I still have no idea what they are!

cooldad

magbrakeman wrote:

Hey just want to say thanks for all the helpful replies and advice, this was all very last minute and I appreciate the patience of everyone that takes it. As for all the less helpful people making comments on my age I'm sorry I'm trying to do something with my life, I hope you enjoy bullying children on the internet.
Henry

Er you are not a child, and take it as constructive criticism. It's a big bad world out there.

And if you've left it to the last minute, you can't really blame anyone else.

However, as no one seems to have a clue what you mean, some additional info into what you are thinking would be useful. As it is, any info you get will be pretty pointless.

figbat

The problem with electromagnetic brakes (contactless) which appear to be implied by the questions asked, is that they work best at high speeds, with their effectiveness dropping with speed until they don't work at all at a standstill. That’s why in road vehicles they are supplementary to friction brakes. And yes, you have to dump the heat that is generated as a consequence of the induced current somewhere.

As an addition to rim or disk brakes I could see them being useful on a long descent for controlling speed without overheating friction surfaces, but then that’s extra weight for an outcome a modulated friction brake can already do. And magnets are heavy.

Ahm oot.

02gf74

There is magnetic brakes and eddy current/induction brakes, both use magnetic fields.

For the latter, see here

https://youtu.be/mopfuVfeIhc

Vino'sGhost

He may well be using ferous core magnetic lever effect.

The bikes mass will essentially be offset against that of the earth effectivley slowing the vehicle down. The down side is the rider will always end up facing in the same direction irrespective of trail drirection. Of course there is also a degree or two of drift each year .

The xtr version could have glonas and gps based corrections to offset the magnetic orientation challenges but even then it all might go pear shaped in the woods or around tall buildings.