L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III

That's an additional safety device, it pressurize the parking brake
spring in a separate can at the end, you may see:
http://web.syr.edu/~wposcarl/AirBrak...Photo-Copy.jpg to
release the shoes to move. We still use air pressure to stop, just like
you use hydraulic fluid pressure to stop.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Peter Parker wrote:
>
> Don't forget drums on 18 wheelers work in reverse. I mean instead of
> pushing the brake pedal to produce hydraulic pressure to make the shoes
> brake, you push the pedal to release the air that hold the brakes from
> braking. IOW, the air released that normally keeps the drums from braking
> on an 18 wheeler is easier to brake with than hydraulic pressured brake
> system. If you loose air in the brake lines of an 18 wheeler you lock
> up the brakes and that is not good.
>
> > God Bless America, ßill O|||||||O
> >mailto:-------------------- http://www.----------.com/
> >
> >Dave Milne wrote:
> >>
> >> I have never had a vehicle with drums that would brake well. Drums are
> >> cheaper,
> >> that's all.
> >>
> >> Dave Milne, Scotland
> >> '91 Grand Wagoneer, '99 TJ
>
> --
> Jeeps and dubs and everything's nice...
> Replace nospam with jetta for e-mail

DaveW

Dave Milne wrote:

> No I wasn't. However, with drums, they hotter they get, the bigger they
> get and the more travel they require; with disks the hotter they get, the
> closer they get. As for 18 wheeler trucks; they are tiny compared to
> trains,
> which use discs.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

Actually, although modern passenger trains tend to use disc brakes in
addition, most railroad equipment I've ever encountered uses neither a
disc or drum. They use a "tread brake", that is a cast iron or composite
brake shoe that is applied to the outside of the wheel, on the running
surface. Iron on steel. Smokes sometimes, doesn't catch on fire!

Regards,

DAve

--
Fan of the Late, Great Southern Pacific and the Small Old Santa Fe

DaveW

Dave Milne wrote:

> No I wasn't. However, with drums, they hotter they get, the bigger they
> get and the more travel they require; with disks the hotter they get, the
> closer they get. As for 18 wheeler trucks; they are tiny compared to
> trains,
> which use discs.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

Actually, although modern passenger trains tend to use disc brakes in
addition, most railroad equipment I've ever encountered uses neither a
disc or drum. They use a "tread brake", that is a cast iron or composite
brake shoe that is applied to the outside of the wheel, on the running
surface. Iron on steel. Smokes sometimes, doesn't catch on fire!

Regards,

DAve

--
Fan of the Late, Great Southern Pacific and the Small Old Santa Fe

DaveW

Dave Milne wrote:

> No I wasn't. However, with drums, they hotter they get, the bigger they
> get and the more travel they require; with disks the hotter they get, the
> closer they get. As for 18 wheeler trucks; they are tiny compared to
> trains,
> which use discs.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

Actually, although modern passenger trains tend to use disc brakes in
addition, most railroad equipment I've ever encountered uses neither a
disc or drum. They use a "tread brake", that is a cast iron or composite
brake shoe that is applied to the outside of the wheel, on the running
surface. Iron on steel. Smokes sometimes, doesn't catch on fire!

Regards,

DAve

--
Fan of the Late, Great Southern Pacific and the Small Old Santa Fe

DaveW

Dave Milne wrote:

> No I wasn't. However, with drums, they hotter they get, the bigger they
> get and the more travel they require; with disks the hotter they get, the
> closer they get. As for 18 wheeler trucks; they are tiny compared to
> trains,
> which use discs.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ

Actually, although modern passenger trains tend to use disc brakes in
addition, most railroad equipment I've ever encountered uses neither a
disc or drum. They use a "tread brake", that is a cast iron or composite
brake shoe that is applied to the outside of the wheel, on the running
surface. Iron on steel. Smokes sometimes, doesn't catch on fire!

Regards,

DAve

--
Fan of the Late, Great Southern Pacific and the Small Old Santa Fe

jbjeep

>>Actually, although modern passenger trains tend to use disc brakes in
>>addition, most railroad equipment I've ever encountered uses neither a
>>disc or drum. They use a "tread brake", that is a cast iron or composite
>>brake shoe that is applied to the outside of the wheel, on the running
>>surface. Iron on steel. Smokes sometimes, doesn't catch on fire!
>>

so what makes all the sparks that sets off the fires out here? we get fires all the
time in the summer months right along the railroad tracks. had a big one last summer
in portland - nearly lost some houses because of it.

jbjeep

>>Actually, although modern passenger trains tend to use disc brakes in
>>addition, most railroad equipment I've ever encountered uses neither a
>>disc or drum. They use a "tread brake", that is a cast iron or composite
>>brake shoe that is applied to the outside of the wheel, on the running
>>surface. Iron on steel. Smokes sometimes, doesn't catch on fire!
>>

so what makes all the sparks that sets off the fires out here? we get fires all the
time in the summer months right along the railroad tracks. had a big one last summer
in portland - nearly lost some houses because of it.

jbjeep

>>Actually, although modern passenger trains tend to use disc brakes in
>>addition, most railroad equipment I've ever encountered uses neither a
>>disc or drum. They use a "tread brake", that is a cast iron or composite
>>brake shoe that is applied to the outside of the wheel, on the running
>>surface. Iron on steel. Smokes sometimes, doesn't catch on fire!
>>

so what makes all the sparks that sets off the fires out here? we get fires all the
time in the summer months right along the railroad tracks. had a big one last summer
in portland - nearly lost some houses because of it.

jbjeep

>>Actually, although modern passenger trains tend to use disc brakes in
>>addition, most railroad equipment I've ever encountered uses neither a
>>disc or drum. They use a "tread brake", that is a cast iron or composite
>>brake shoe that is applied to the outside of the wheel, on the running
>>surface. Iron on steel. Smokes sometimes, doesn't catch on fire!
>>

so what makes all the sparks that sets off the fires out here? we get fires all the
time in the summer months right along the railroad tracks. had a big one last summer
in portland - nearly lost some houses because of it.

DougW

jbjeep did pass the time by typing:
>>> Actually, although modern passenger trains tend to use disc brakes in
>>> addition, most railroad equipment I've ever encountered uses neither a
>>> disc or drum. They use a "tread brake", that is a cast iron or composite
>>> brake shoe that is applied to the outside of the wheel, on the running
>>> surface. Iron on steel. Smokes sometimes, doesn't catch on fire!
>>>
>
> so what makes all the sparks that sets off the fires out here? we get fires
> all the time in the summer months right along the railroad tracks. had a big
> one last summer in portland - nearly lost some houses because of it.

Train operators tossing butts from the window?

Sparking skunks?

Lowriders dragging across train crossings?

--
DougW