[rallyman]

Hi all,

As a recently converted rev-head, I've now jumped onto doing handbrake turns...both 180 and once I'm good enough, 360 (although I'm sure I'll never get that good!).

But anyway, just wanted to know the technical side of how the handbrake actually works (ie. the mechanisms that lock the rear wheels)? I've heard someone say that it's only a clip of some sort that does it.

Can anyone help me out please? Thanks.

 

[MADXF]

it just pulls a lever that pushs the pistons against the rotors.

well thats how the XF ones work

 

[FTEfan]

Depends on the vehicle. On drum braked cars a lever moves out and pushes the brake shoes against the drum. I think the current Falcon's park brake does this.

 

[Aussie Pete]

Gee, I thought a handbrake worked like this:

You meet a girl, decide it ain't so bad, possibly get married and before long you notice something holding you back from all the stuff you used to do with your mates. That's how a handbrake REALLY works. You can still go forward, sometimes reverse, but there's this 'dragging you back' effect that can be hard to recognise until someone else tells you or the light registers in your mind.

I can also tell you how an airbag works if you like:

You get a nice car, manual V8 sort of thing, and you find a half decent piece of road to give it a bit of stick. But the moment the speed rises and any sort of G-forces are sensed by the airbag device, you hear a loud outburst and your progress is halted immediately. Some people can have ringing in the ears for some time after the airbag goes off. Airbags of this sort are normally only deployed in the passenger seat (just in case you wanted to know). Note that 'airbag' and 'SRS' are not necessarily the same thing.

 

[AusXH]

Gee, I thought a handbrake worked like this:

You meet a girl, decide it ain't so bad, possibly get married and before long you notice something holding you back from all the stuff you used to do with your mates. That's how a handbrake REALLY works. You can still go forward, sometimes reverse, but there's this 'dragging you back' effect that can be hard to recognise until someone else tells you or the light registers in your mind.

I can also tell you how an airbag works if you like:

You get a nice car, manual V8 sort of thing, and you find a half decent piece of road to give it a bit of stick. But the moment the speed rises and any sort of G-forces are sensed by the airbag device, you hear a loud outburst and your progress is halted immediately. Some people can have ringing in the ears for some time after the airbag goes off. Airbags of this sort are normally only deployed in the passenger seat (just in case you wanted to know). Note that 'airbag' and 'SRS' are not necessarily the same thing.

You poor [email protected] I think you need a emoticon with a chain around its neck.

 

[Futura97]

Hi all,

As a recently converted rev-head, I've now jumped onto doing handbrake turns...both 180 and once I'm good enough, 360 (although I'm sure I'll never get that good!).

Gotta love doing those handbrake turns. I think we should discuss the fun we have all had at one stage doing hand brakey's.

I was once delivering a pizza to a house and it was late at night, not to mention the pizza itself was late. I had my GF in the car with me when we were driving down the street looking for number 42. All of a sudden I heard her say "there it is...". If I hadn't been driving so fast I wouldn't have had to do what I did. I ripped up the handbrake and swung the car around 180 deg. It was followed quickly by a very quick slap across the face, and no talking for a long time. Not to mention she hasn't been in the car with me ever since.

It was all fun though.

The best thing about hand brakeys is you can do it in almost any car with a good handbrake. No matter if its front wheel drive.

As for your 360 turns takes ALOT of speed or wet conditions and alot of space to start of with. Try and find a paddock of gravel and practice. The more practice the better.

Cheers
Matt

 

[jaytyn]

doesnt do your tyres any good you mgiht get some flat spots.

On the AU's they use shoes dont they? how do they work?

 

[FTEfan]

The AUs parkbrake works the same as on drum brakes. My old 121 used to do handbrake turns all the time. Best was missing a turnin civic and haveing to turn PDQ. 60km/h yank steering wheel to the right, pull handbrake, drop handbrake, slam into 1st gear, rop clutch and prepare for torque steer. Been in a V6 Camry doing a handbrake turn at 100km/h. Axle tramp and wheel spin all the way through 1st and 2nd!

 

[rallyman]

Re: Re: Workings of the handbrake..need help!

Gotta love doing those handbrake turns. I think we should discuss the fun we have all had at one stage doing hand brakey's.

I have to admit that I learnt almost all of it in a VX Commodore.
You see, a few friends of mine decided to head up to Canberra for a weekend (hey, they serve burbon and coke JUGS up there! That was enough reason for us!!). So we hired a VX Commodore and when we reached Albury-Wodonga, it was about midnight.
Well, my friend said "There's a really good restaurant up ahead" so we just kept going past all the servos and take-away places.
But then, we say the street lights were about to end so I said "Where is this place?" and he said "Oh...we might have missed it!". So I quickly whipped the handbrake up and did a 180 out of nowhere (not easy with 5 people in the car but the road was wet). Some of the passengers who were half asleep were fully awake now as they're not used to me driving like that (I'd never do it in my car). But yeah, all that weekend, that car copped a thrashing! It was mostly raining in Canberra so tyre wear wasn't a problem.

As for the 360, the day I buy my own airfield, I'll start practicing those.

But as for conventional AU/VX handbrakes, is there a chance of them failing if used too brutally?

 

[MADXF]

Had a look at brakes on an AU ute the other day and it seems that it has a lever the pushes directly onto the piston(s) or pushes onto some sort of smaller mastercylinder type thing.

 

[EA S]

Having had the pleasure of pulling rear calipers apart on XF, which is fundamentally same design as EA up to I don't know when, the handbrake cable moves a lever on the caliper body which actuates a helical screw inside the caliper which actuates the piston. This is independent of the hydraulic system which operates the piston directly. The design is flawed and the helical screw binds up and you end up with dragging pads and interesting noises from the rear, which is why I have pulled them apart and put kits in them etc and why I now know that it is all a waste of time on a prick of a job without the right piston tool and you just get reco calipers at the first sign of trouble.

 

[Aussie Pete]

Okay, obviously my definitions of handbrake went unheeded. So, I have just one thing to say; basically the AU IRS cars have a spooky feeling handbrake action which is soft and gives the impression it won't work. It does, but spooky none the less!

 

[EA S]

You get a nice car, manual V8 sort of thing, and you find a half decent piece of road to give it a bit of stick. But the moment the speed rises and any sort of G-forces are sensed by the airbag device, you hear a loud outburst and your progress is halted immediately. Some people can have ringing in the ears for some time after the airbag goes off. Airbags of this sort are normally only deployed in the passenger seat (just in case you wanted to know). Note that 'airbag' and 'SRS' are not necessarily the same thing.

Earlier models without airbags have a sound warning system on the front passenger side which signals normal driving by emitting a loud droning noise most of the time, which can usually safely be ignored if the driver just grunts now and then, but under unusual conditions it changes suddenly to a sharp piercing noise which in extreme situations, like normal cornering, is accompanied by theatrical grabs at the panic handle. Locomotives used to, maybe still do, have a related device to keep crews awake which required the driver or fireman to push a large button every half minute or so as the sound increases from nothing after each push to stop it getting to deafening level. This probably replaced the system found in pre-airbag cars as there is no way known of shutting that system up if it doesn't want to.

 

[Aussie Pete]

EA S has indeed discovered something along the lines of the truth. The locomotive item you are referring to was called a 'Dead Man' switch or handle. Rather appropriate in this context :s6:

 

[FTEfan]

My car has a variation of the dead man switch. If I enter a roundabout to quick in the wet and the tail slides, the left hand is reduced to pulp. Good thing I drive an auto.:s5

 

[EA S]

EA S has indeed discovered something along the lines of the truth. The locomotive item you are referring to was called a 'Dead Man' switch or handle. Rather appropriate in this context :s6:

I can speak on this with some authority from my distant days as a shunter with the Vic Railways.

The button I was referring to was on the ceiling of the loco and was intended to keep the crew awake by forcing at least one of them to reach above their head frequently to shut it off, but I can't remember its name. Any decent fireman (i.e. co-driver, navigator, whatever) could perform this task without giving any visible sign of being woken up, or being distracted from reading their book.

A dead man's handle is different. If the grip on it is released then the engine drops to idle or whatever and the brakes are applied automatically, so that trains can't keep running with a corpse at the wheel (otherwise how could you tell if railway staff were dead?).

A similar principle applies to a living man's handle in another non-locomotive context, but in view of recent cautions about dropping the tone of this site I won't go into it.