hydraulic brake actuation

Am researching the brake system for my glider project and am pretty
sure a disc brake is the way to go. The cost for a suitable drum brake
is about 2x what a disc brake from Grove or Matco costs, Azuza makes
drum brakes, but they don't seem robust enough for my needs.

I plan on using a bike grip type handle to actuate the brake, not a
problem with a drum brake, but not so easy with the disc brake, as far
as what I have been able to find out. There is a stick mounted hand
grip style Matco makes, but it has the reservoir attached and will
interfere with my control stick geometry.

What I am leaning towards is a bike grip, with the cable running to a
lever with mechanical advantage to actuate the hyrdraulic master
cylinder. (DRN.........you sent me a pic of this?)

Do any of you guys out there with disc brakes have a bike grip type
actuator? and how does it actuate the master cylinder?

Do not want to brake actuated by the airbrake circuit, nor a heel
brake.

I did a search of this group on this subject, and did find some useful
info, but wanted to start a more specific thread..................ok,
so I am lazy!

TIA,
Brad

Brad,
make your own handle.
On my projects I used 5/16" 6061 Aluminium.
You can shape it and size it to meet your needs. Make it a bit longer and
you can use two hands for max braking.
I used Matco and a generic master cylinder and I was able, with two hands
to leave rubber on the pavement.
Udo

At 18:26 07 January 2009, Brad wrote:
Am researching the brake system for my glider project and am pretty
sure a disc brake is the way to go. The cost for a suitable drum brake
is about 2x what a disc brake from Grove or Matco costs, Azuza makes
drum brakes, but they don't seem robust enough for my needs.

I plan on using a bike grip type handle to actuate the brake, not a
problem with a drum brake, but not so easy with the disc brake, as far
as what I have been able to find out. There is a stick mounted hand
grip style Matco makes, but it has the reservoir attached and will
interfere with my control stick geometry.

What I am leaning towards is a bike grip, with the cable running to a
lever with mechanical advantage to actuate the hyrdraulic master
cylinder. (DRN.........you sent me a pic of this?)

Do any of you guys out there with disc brakes have a bike grip type
actuator? and how does it actuate the master cylinder?

Do not want to brake actuated by the airbrake circuit, nor a heel
brake.

I did a search of this group on this subject, and did find some useful
info, but wanted to start a more specific thread..................ok,
so I am lazy!

TIA,
Brad

I built such a system for my former AS-W12 using a Cleveland system.
Worked fine but make sure the entire system is as stiff as you can
possibly make it. Use heavy motorcycle bowden cable and make the run
as short as possible. Also make sure the master cylinder mount is
rigid.

The ratios from brake handle throw (e.g., what is the max throw you
can get with your hand on the stick) to the throw on the master
cylinder actuator is an interesting geometric cut-an-fit. Making your
own handle will help a lot.

I much prefer spoiler-actuated brakes due to the additional force you
can apply with your entire arm/shoulder, the fact that both drag
devices are appropriately on one handle and the difficulty in mixing
fine-scale pitch/roll inputs on the stick with the gross-scale motor
skills of pulling like hell on the wheel brake.

wrote:
I built such a system for my former AS-W12 using a Cleveland system.
Worked fine but make sure the entire system is as stiff as you can
possibly make it. Use heavy motorcycle bowden cable and make the run
as short as possible. Also make sure the master cylinder mount is
rigid.

The ratios from brake handle throw (e.g., what is the max throw you
can get with your hand on the stick) to the throw on the master
cylinder actuator is an interesting geometric cut-an-fit. Making your
own handle will help a lot.

I much prefer spoiler-actuated brakes due to the additional force you
can apply with your entire arm/shoulder, the fact that both drag
devices are appropriately on one handle and the difficulty in mixing
fine-scale pitch/roll inputs on the stick with the gross-scale motor
skills of pulling like hell on the wheel brake.


I installed a Tost disc system (modified Cleveland) in my Discus A.
Just uses bicycle cable, and the run is from the handle on the stick all
the way back to the master cylinder alongside the wheel well. The
problem was that the lever on the stick (designed for a drum brake) hit
the stick before there was much braking action. This was due both to
the shape of the lever and the long run of stretchy cable.

After spending considerable time surfing bicycle shops on the internet,
and ordering several different bicycle brake handles, I found one that
is a perfect replacement for the SH handle. It is shorter and curved
away from the stick, and allows you to apply any pressure you want
without the handle hitting the stick.

Thus, you can make such a system work with bicycle components.

On Jan 7, 1:26*pm, Brad wrote:
...
What I am leaning towards is a bike grip, with the cable running to a
lever with mechanical advantage to actuate the hyrdraulic master
cylinder. (DRN.........you sent me a pic of this?)

The picture I sent you was spoiler-actuated (which I still
recommend). I just emailed you and Bob pictures of a
setup as you describe above.

Hope it helps !
See ya, Dave "YO electric"

PS: I have a Matco disc brake and wheel from an abandoned
project (disc brake mod kit for LS-6, almost finished) and an
actuator too.
Somewhere in the back of my shop under a decade's detritus...
Contact me if you're interested...

On Jan 7, 3:38*pm, Greg Arnold wrote:
wrote:
I built such a system for my former AS-W12 using a Cleveland system.
Worked fine but make sure the entire system is as stiff as you can
possibly make it. *Use heavy motorcycle bowden cable and make the run
as short as possible. *Also make sure the master cylinder mount is
rigid.

The ratios from brake handle throw (e.g., what is the max throw you
can get with your hand on the stick) to the throw on the master
cylinder actuator is an interesting geometric cut-an-fit. *Making your
own handle will help a lot.

I much prefer spoiler-actuated brakes due to the additional force you
can apply with your entire arm/shoulder, the fact that both drag
devices are appropriately on one handle and the difficulty in mixing
fine-scale pitch/roll inputs on the stick with the gross-scale motor
skills of pulling like hell on the wheel brake.

I installed a Tost disc system (modified Cleveland) in my Discus A.
Just uses bicycle cable, and the run is from the handle on the stick all
the way back to the master cylinder alongside the wheel well. *The
problem was that the lever on the stick (designed for a drum brake) hit
the stick before there was much braking action. *This was due both to
the shape of the lever and the long run of stretchy cable.

After spending considerable time surfing bicycle shops on the internet,
and ordering several different bicycle brake handles, I found one that
is a perfect replacement for the SH handle. *It is shorter and curved
away from the stick, and allows you to apply any pressure you want
without the handle hitting the stick.

Thus, you can make such a system work with bicycle components.

Um, why didn't you just replace the Bowden cable with something
more appropriate ??
See ya, Dave

Um, why didn't you just replace the Bowden cable with something
more appropriate ??
See ya, Dave- Hide quoted text -

- Show quoted text -

Such as?
I've been playing with this a bit too. I built a new cable using
motorcycle brake cable, (BTW, cable, and end fittings can be found at
Flanders web site, very reasonable) which is considerably stouter than
anything found on a bicycle. I'm still stuck with the very limited
cable movement (about 1/2"). The original lever very nearly hits the
instrument panel, so extending it isn't an option. I could set up the
master cylinder actuator to deliver more stroke than the cable
movement, but I need to test that to see if I can generate enough
pressure. I'm MOST inclined to follow Mark's advice and set it up on
the spoiler handle, but only after I've wasted several weeks trying to
make the joystick lever work!

On Jan 7, 4:14*pm, Uncle Fuzzy wrote:
Um, why didn't you just replace the Bowden cable with something
more appropriate ??
See ya, Dave- Hide quoted text -

- Show quoted text -

Such as?

Stiffer housing, stronger cable, matching end-fittings...
Reduce required throw on master cylinder.

I've been playing with this a bit too. *I built a new cable using
motorcycle brake cable, (BTW, cable, and end fittings can be found at
Flanders web site, very reasonable) which is considerably stouter than
anything found on a bicycle. *I'm still stuck with the very limited
cable movement (about 1/2"). *The original lever very nearly hits the
instrument panel, so extending it isn't an option. *I could set up the
master cylinder actuator to deliver more stroke than the cable
movement, but I need to test that to see if I can generate enough
pressure. *I'm MOST inclined to follow Mark's advice and set it up on
the spoiler handle, but only after I've wasted several weeks trying to
make the joystick lever work!

I'd recommend the spoilers as well.

Thanks for the pointer to Flanders cable parts:
http://www.flandersco.com
Anybody know if there's a site where these parts can be ordered
on the web (it looks like Flanders isn't set up for web orders) ?

Best Regards, Dave "YO electric"

DRN wrote:
On Jan 7, 3:38 pm, Greg Arnold wrote:
wrote:
I built such a system for my former AS-W12 using a Cleveland system.
Worked fine but make sure the entire system is as stiff as you can
possibly make it. Use heavy motorcycle bowden cable and make the run
as short as possible. Also make sure the master cylinder mount is
rigid.
The ratios from brake handle throw (e.g., what is the max throw you
can get with your hand on the stick) to the throw on the master
cylinder actuator is an interesting geometric cut-an-fit. Making your
own handle will help a lot.
I much prefer spoiler-actuated brakes due to the additional force you
can apply with your entire arm/shoulder, the fact that both drag
devices are appropriately on one handle and the difficulty in mixing
fine-scale pitch/roll inputs on the stick with the gross-scale motor
skills of pulling like hell on the wheel brake.
I installed a Tost disc system (modified Cleveland) in my Discus A.
Just uses bicycle cable, and the run is from the handle on the stick all
the way back to the master cylinder alongside the wheel well. The
problem was that the lever on the stick (designed for a drum brake) hit
the stick before there was much braking action. This was due both to
the shape of the lever and the long run of stretchy cable.

After spending considerable time surfing bicycle shops on the internet,
and ordering several different bicycle brake handles, I found one that
is a perfect replacement for the SH handle. It is shorter and curved
away from the stick, and allows you to apply any pressure you want
without the handle hitting the stick.

Thus, you can make such a system work with bicycle components.

Um, why didn't you just replace the Bowden cable with something
more appropriate ??
See ya, Dave


I don't know what would be "more appropriate" than an arrangement that
works perfectly.

On Jan 7, 4:56*pm, Greg Arnold wrote:
DRN wrote:
On Jan 7, 3:38 pm, Greg Arnold wrote:
wrote:
I built such a system for my former AS-W12 using a Cleveland system.
Worked fine but make sure the entire system is as stiff as you can
possibly make it. *Use heavy motorcycle bowden cable and make the run
as short as possible. *Also make sure the master cylinder mount is
rigid.
The ratios from brake handle throw (e.g., what is the max throw you
can get with your hand on the stick) to the throw on the master
cylinder actuator is an interesting geometric cut-an-fit. *Making your
own handle will help a lot.
I much prefer spoiler-actuated brakes due to the additional force you
can apply with your entire arm/shoulder, the fact that both drag
devices are appropriately on one handle and the difficulty in mixing
fine-scale pitch/roll inputs on the stick with the gross-scale motor
skills of pulling like hell on the wheel brake.
I installed a Tost disc system (modified Cleveland) in my Discus A.
Just uses bicycle cable, and the run is from the handle on the stick all
the way back to the master cylinder alongside the wheel well. *The
problem was that the lever on the stick (designed for a drum brake) hit
the stick before there was much braking action. *This was due both to
the shape of the lever and the long run of stretchy cable.

After spending considerable time surfing bicycle shops on the internet,
and ordering several different bicycle brake handles, I found one that
is a perfect replacement for the SH handle. *It is shorter and curved
away from the stick, and allows you to apply any pressure you want
without the handle hitting the stick.

Thus, you can make such a system work with bicycle components.

Um, why didn't you just replace the Bowden cable with something
more appropriate ??
See ya, Dave

I don't know what would be "more appropriate" than an arrangement that
works perfectly.

Apologies if I mis-understood your email.
You say you have "long run of stretchy cable".
If you didn't replace it, you're using up lots of travel stretching
the cable.
If you fixed the cable problem, you wouldn't have needed to change the
handle ?
And you would have better leverage ?

Sounds "adequate" but hardly "perfect", especially as soon
as any additional deficiency develops...

Sorry if I mis-understand !
Best Regards, Dave "YO electric"