can i use a hydraulic hand brake , and will it pass the test?
quote:
can i use a hydraulic hand brake , and will it pass the test?
the answer is no ,next question please
next question to conrodkid, on which page in the sva book does it say i cant use a hydro. hand brake?
Bass
After a little reading of the manual.
It doesnt say yes or no,but it does say it must be controled independant of the service brake.
So i presume this means you would need a seperate master cylinder of which the fluid reservoir must be accessible.
Then there would be another warning light for fluid level.
Seems like a lot of hard work when the cable version will do,but i suppose it depends on the braking system you want to use.
Bob is correct but why would you want to use a hydraulic handbrake, what benefits would it have over the cable. Better feel? Hmmm.
quote:
Bob is correct but why would you want to use a hydraulic handbrake, what benefits would it have over the cable. Better feel? Hmmm.
Re Bass,s reply read construction and use.
Is this the bit you mean?
"using a control which is independent of the service brake, and capable once applied of being maintained in the 'on' position solely by a mechanical
means."
Alan
You got it mate!
how can it be com. independant if i use the same shoes/drums as main b/system? thats the control of the h/brake, not how it works.
Where do you stop? Do you go to the wheel and the tyre as well we use your theory, even the vehicles that have both pads and shoes at the rear use the same rotor, wheel and tyre. The SVA talks about the mechanical means of applying the brakes, if you look at the drum shoe setup or even the disc setup for dual brakes you will notice that they operate independantly of each other. The slave cylinder at the top pushes against a solid bit at the base of the shoes and the handbrake works against the cable, normally at the bottom, and an auto adjusting bar 2/3rds the way up.
Old jags (XJ6/12) have a completely seperate handbrake caliper on the inboard discs,but thats the only car i can think of.
BASS,do you have a preference to hydro handbrake for a reason?
Looks like it could be hard work,but it is a thought.
bob , it would simple to put a m/cylender in the line to work the h/brake.
to bob , so did rover2000,3500, mk 2 jags and fords
austin A 35 had a hand and foot brake that worked of the same circuit
So did the Austin 7. And it had friction dampers. Those were the days. I can remember when .....
Alan
I think the hydro hand brake is a good idea but,the problem is the wording of the manual.
The mechanism that operates the hand brake must be seperate from the service brake.
I think this means you cant put a m/c in line,and must run a seperate system.
In the end the best way around this is to contact your local SVA test centre,as we are only summising.
I think i'll stick with a cable and keep it simple 
You can't have another master cylinder in the line without affecting foot brake performance. You would need a non return valve which defeats the purpose and a solution would over complicate the idea.
Dunc
You hit the nail right on the head there mate.
Keep it simple,and cheap to maintain
Can someone explain something to me. On a std Ford rear hub, the foot brake pressure is transfered via fluid to a wheel cylinder (that expands to push
shoes blah blah .. )
The hand brake uses a cable and leaver to push the shoe.
If you use fluid transfer in place of cable, how do you actuate the leaver behind the shoe?
You wouldn't use the lever at all, you would have a another wheel cylinder at the bottom instead for use by the handbrake only. When the hanbrake is off though the bottom of the shoes would need to act against a solid bar like on standard so that the foot brake won't feel spongy at best or non existant at worst. This would be because if you just had it acting on the handbrake wheel cylinder, applying the footbrake would force the fluid up the handbrake line, through the hole in the master cylinder and into the resevoir. A bit like when your changing you brake pads and you force the cylinder back into the caliper with a g clamp and the fluid that you topped up last week starts to wee out of the top of the lid.
So in theory you could have one top and bottom operated by the foot brake to give better braking, at the expense of pedal travel .. .
In theory yes, but in theory you can also balance a cube on one corner on top of a ball that's sitting on the point of a pyramid. But pedal travel doesn't have to suffer as a result if you use 2 smaller diameter wheel cylinders and or a larger diameter master cylinder. You might have noticed when driving a drum rear car that if you pull the handbrake on just before you brake the pedal feels firmer with less travel. That would be similar to what you're asking but where would you put the handbrake?
no you havent got it. you put the m/c in line like they do when they convert to invalid cars. the f/brake pressure goes through the h/brake m/c, no tank or one way valves.
You're right, we're all too thick to understand you. But if you're plan is to put a handbrake Master cylinder in line with the footbrake then it will fail the SVA because it isn't an independant system.
but it says. secondary. capable of operating via either half of a split cicuit service brake system on at least 2 wheels in the event of failure of the service brake or power assistance
Just to add my 2p worth, I used to rally cars in the distant past. Hydraulic handbrakes were the norm but, and this is the catch, if there was no
cable backup system, the car would fail scrutineering and not be allowed to start. This was overcome by fitting a dummy cable that went to the rear
brakes but did nothing! (oops don't tell the scrutineers) There was no way of telling wether it was the cable or hydraulics that actuated the
brake.
Marcus
to dunc, d jenkins ect the idea to use a hydro h/brake is so you dont have to keep freeing off the mechanical part that always seizes up and leaves you with no h/brake and a long f/brake.
To bass, don't know where you are but here in scotland we have this stuff called copper grease that stops things seizing up and stop working. Try a
word search for it on google. Are you still talking about drums and shoes or leather strap round the axle? 
Copper grease has made it to North Nottinghamshire Dunc, just as a point of reference.
dunk do you put it under you kilt ? the part that seizes up is where you cant grease.
Yeh I do. Need the copper grease because of the high operating temperatures, especially after thrusting hard for 6 or 7 hours. Nothing else will
do.
base, as for can't put it there because of the part that seizes up is where you cant grease. Why is that? the only part that you can't put grease is
the friction surfaces, I don't have a clue what you're talking about anymore, are you still talking about the brakes or your tackle seizing up through
lack of use.
Hey hippy, were you at Stoneleigh on sunday? from your pic I thought I saw someone like you at the locost bit that became the locust but on the
monday.