Winch Way Is Up !!

There are some very nice advantages to a winch (wouldn't think twice
about getting a launch even if the weather does not look so great, we
had some great fun launching to landing circuit just for the heck of
it when it was raining last summer). We've got a package deal in our
club, unlimited launches for a reasonable price. It's just very
economical (make no mistake though, I do appreciate the convenience of
an aerotow as well). Still, a winch launch will teach you how to make
the best of the conditions as you don't have much time to find a
thermal.

We've got a "factory built" winch from Germany a few years back, top
of the notch with turbos and whatnot- if you're interested, have a
look at http://www.saunalahti.fi/kily/paasivu.htm. Click on "kalusto",
the fourth button on the left frame and then "vintturi" on the right
frame. Sorry, it's all in Finnish :-)

Kind regards,

Antti

Antti --

I really appreciate that photo. It appears to be a twin drum machine
with right angle drives to each drum. Do you know how the builders got
that power to go around the corner, that is, does it use a conventional
automotive-type differential, angle gears, or what?

Thanks again,

BJ

Antti Glad wrote:

There are some very nice advantages to a winch (wouldn't think twice
about getting a launch even if the weather does not look so great, we
had some great fun launching to landing circuit just for the heck of
it when it was raining last summer). We've got a package deal in our
club, unlimited launches for a reasonable price. It's just very
economical (make no mistake though, I do appreciate the convenience of
an aerotow as well). Still, a winch launch will teach you how to make
the best of the conditions as you don't have much time to find a
thermal.

We've got a "factory built" winch from Germany a few years back, top
of the notch with turbos and whatnot- if you're interested, have a
look at http://www.saunalahti.fi/kily/paasivu.htm. Click on "kalusto",
the fourth button on the left frame and then "vintturi" on the right
frame. Sorry, it's all in Finnish :-)

Kind regards,

Antti

Most European winches are hydraulic drives.

"Bob Johnson" wrote in message
...
Antti --

I really appreciate that photo. It appears to be a twin drum machine
with right angle drives to each drum. Do you know how the builders got
that power to go around the corner, that is, does it use a conventional
automotive-type differential, angle gears, or what?

Thanks again,

BJ

Antti Glad wrote:

There are some very nice advantages to a winch (wouldn't think twice
about getting a launch even if the weather does not look so great, we
had some great fun launching to landing circuit just for the heck of
it when it was raining last summer). We've got a package deal in our
club, unlimited launches for a reasonable price. It's just very
economical (make no mistake though, I do appreciate the convenience of
an aerotow as well). Still, a winch launch will teach you how to make
the best of the conditions as you don't have much time to find a
thermal.

We've got a "factory built" winch from Germany a few years back, top
of the notch with turbos and whatnot- if you're interested, have a
look at http://www.saunalahti.fi/kily/paasivu.htm. Click on "kalusto",
the fourth button on the left frame and then "vintturi" on the right
frame. Sorry, it's all in Finnish :-)

Kind regards,

Antti

On Fri, 31 Oct 2003 16:10:15 -0600, Bob Johnson
wrote:

Antti --

I really appreciate that photo. It appears to be a twin drum machine
with right angle drives to each drum. Do you know how the builders got
that power to go around the corner, that is, does it use a conventional
automotive-type differential, angle gears, or what?

Supacats, anyway, have a massive purpose designed gearbox mounted
between the twin drums. It is driven via a fluid clutch and drives the
two outputs via dog clutches as well as the oscillating pay-on arms.
There are three separate brake systems (one on each drum, plus one on
the output side of the fluid clutch). The drum brakes have independent
hydraulic circuits connected to separate brake levers. The input brake
and the output dog clutches are mechanically interconnected on a
single lever - it moves sideways to select left, right or no drum and
back to apply the brake on the clutch output. In addition there are
payout brake levers that apply light pressure to the drum calipers
while the cable is being pulled out.

The separate throttle connects to the Deutz diesel via a profiled cam
that gives a more or less linear power response. By that I mean that
more or less equal movements give similar power increments over the
whole range. It makes smooth launches a lot easier.

Safety: pulling rather than pushing the throttle cuts the motor. Both
guillotines are operated simultaneously from an in-cab hydraulic
circuit or, if this fails, each can be fired mechanically from
outside. A flashing yellow light on top the cap operates when the
winch is running and in gear. Nobody touches either cable when its
flashing.

Climate control: there is a diesel burning heater for winter and the
sliding doors open in summer.

HTH

--
martin@ : Martin Gregorie
gregorie : Harlow, UK
demon :
co : Zappa fan & glider pilot
uk :

Martin --

A very good description, thanks for providing it!

As an experiment, we attempted to use the differential that came in the
same heavy duty pickup truck that furnished our 454 c.i. engine. This
unit was mounted as you would expect between the twin drums and one drum
was braked by its respective master cylinder brake lever, leaving the
power to be applied to the opposite drum. This arrangement went fine for
about an half-dozen launches, when the diff over-heated and eventually
gave up the ghost.

Thus we learned that the differential feature as we were using it would
have to be disabled and a couple of dog clutches would have to be
devised in order to turn our winch into a true double-drum unit.

BJ



Martin Gregorie wrote:

On Fri, 31 Oct 2003 16:10:15 -0600, Bob Johnson
wrote:

Antti --

I really appreciate that photo. It appears to be a twin drum machine
with right angle drives to each drum. Do you know how the builders got
that power to go around the corner, that is, does it use a conventional
automotive-type differential, angle gears, or what?

Supacats, anyway, have a massive purpose designed gearbox mounted
between the twin drums. It is driven via a fluid clutch and drives the
two outputs via dog clutches as well as the oscillating pay-on arms.
There are three separate brake systems (one on each drum, plus one on
the output side of the fluid clutch). The drum brakes have independent
hydraulic circuits connected to separate brake levers. The input brake
and the output dog clutches are mechanically interconnected on a
single lever - it moves sideways to select left, right or no drum and
back to apply the brake on the clutch output. In addition there are
payout brake levers that apply light pressure to the drum calipers
while the cable is being pulled out.

The separate throttle connects to the Deutz diesel via a profiled cam
that gives a more or less linear power response. By that I mean that
more or less equal movements give similar power increments over the
whole range. It makes smooth launches a lot easier.

Safety: pulling rather than pushing the throttle cuts the motor. Both
guillotines are operated simultaneously from an in-cab hydraulic
circuit or, if this fails, each can be fired mechanically from
outside. A flashing yellow light on top the cap operates when the
winch is running and in gear. Nobody touches either cable when its
flashing.

Climate control: there is a diesel burning heater for winter and the
sliding doors open in summer.

HTH

--
martin@ : Martin Gregorie
gregorie : Harlow, UK
demon :
co : Zappa fan & glider pilot
uk :

On Tue, 04 Nov 2003 20:30:54 -0600, Bob Johnson
wrote:

Martin --

A very good description, thanks for providing it!

...../....

Thus we learned that the differential feature as we were using it would
have to be disabled and a couple of dog clutches would have to be
devised in order to turn our winch into a true double-drum unit.

The Supacat neutral and third brake is a useful design feature. With
the lever released and the engine running the gear-box is spun up, so
its oil is kept moving (good on a cold day) and the fluid clutch won't
overheat. The combined control makes it easy to rotate the dog a
little to help it engage.


--
martin@ : Martin Gregorie
gregorie : Harlow, UK
demon :
co : Zappa fan & glider pilot
uk :

A winch should never have any doors or windows open while actually
launching. The cab must be fully enclosed, doors and windows shut. The
windows must be of laminated glass or similar, with Lexan or something
similar on the inside surfaces. Any openings not glazed must be protected
with expanded metal sheet, weldmesh or similar.

If the cable breaks, and sooner or later it will, it can get inside the
winch through any opening with amazing ferocity.

One of the Long Mynd amateur winch drivers had the back window slightly
open. The cable broke, came in through the window and attacked his
clothing. He considered he had a very lucky escape, and has given up
driving the winch.

At another club one of the most experienced of all winch drivers parked his
car directly behind the winch and facing it, what he thought was a safe
distance away. This was at a busy club which has done many thousands of
winch launches every year for a very long time. The cable broke and flew
back, trashing the back of his car and round the car to break one of the
front door windows. I saw the car afterwards and asked who had run into
him.

This sort of thing does not happen very often so it takes people by
surprise. It is a completely avoidable risk and is just not worth taking.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Martin Gregorie" wrote in message
...

snip

Climate control: there is a diesel burning heater for winter and the
sliding doors open in summer.

Martin Gregorie

Hi Bill --

After my limited experience with it, I can't help but think that
synthetic is going to be a lot safer and less nasty to work with during
breaks or whenever else it has to be dodged or handled. It's light as a
feather, soft as a baby's butt and stores absolutely no energy.

BJ

"W.J. (Bill) Dean (U.K.)." wrote:

A winch should never have any doors or windows open while actually
launching. The cab must be fully enclosed, doors and windows shut. The
windows must be of laminated glass or similar, with Lexan or something
similar on the inside surfaces. Any openings not glazed must be protected
with expanded metal sheet, weldmesh or similar.

If the cable breaks, and sooner or later it will, it can get inside the
winch through any opening with amazing ferocity.

One of the Long Mynd amateur winch drivers had the back window slightly
open. The cable broke, came in through the window and attacked his
clothing. He considered he had a very lucky escape, and has given up
driving the winch.

At another club one of the most experienced of all winch drivers parked his
car directly behind the winch and facing it, what he thought was a safe
distance away. This was at a busy club which has done many thousands of
winch launches every year for a very long time. The cable broke and flew
back, trashing the back of his car and round the car to break one of the
front door windows. I saw the car afterwards and asked who had run into
him.

This sort of thing does not happen very often so it takes people by
surprise. It is a completely avoidable risk and is just not worth taking.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Martin Gregorie" wrote in message
...

snip

Climate control: there is a diesel burning heater for winter and the
sliding doors open in summer.

Martin Gregorie

Just a few points.

The sort of incidents I described are very rare, which is why people are
sometimes not ready for them and may be caught. It would take many years
of operation with synthetic before one could be sure that it could never
behave as wire occasionally does.

It is not just energy stored in the wire due to elasticity, it is also the
energy due to its weight and speed. Synthetic may have less weight, but it
still has some.

Will winches be designed only for synthetic cable, and never used with wire?
Even if the intention is to use synthetic, the winch should be designed so
that wire can be used, and winch drivers should be trained for this.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Bob Johnson" wrote in message
...

Hi Bill --

After my limited experience with it, I can't help but think that
synthetic is going to be a lot safer and less nasty to work with during
breaks or whenever else it has to be dodged or handled. It's light as a
feather, soft as a baby's butt and stores absolutely no energy.

BJ


"W.J. (Bill) Dean (U.K.)." wrote:

A winch should never have any doors or windows open while actually
launching. The cab must be fully enclosed, doors and windows shut.
The windows must be of laminated glass or similar, with Lexan or
something similar on the inside surfaces. Any openings not glazed must
be protected with expanded metal sheet, weldmesh or similar.

If the cable breaks, and sooner or later it will, it can get inside the
winch through any opening with amazing ferocity.

One of the Long Mynd amateur winch drivers had the back window slightly
open. The cable broke, came in through the window and attacked his
clothing. He considered he had a very lucky escape, and has given up
driving the winch.

At another club one of the most experienced of all winch drivers parked
his car directly behind the winch and facing it, what he thought was a
safe distance away. This was at a busy club which has done many
thousands of winch launches every year for a very long time. The
cable broke and flew back, trashing the back of his car and round the
car to break one of the front door windows. I saw the car afterwards
and asked who had run into him.

This sort of thing does not happen very often so it takes people by
surprise. It is a completely avoidable risk and is just not worth
taking.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Martin Gregorie" wrote in message
...

snip

Climate control: there is a diesel burning heater for winter and the
sliding doors open in summer.

Martin Gregorie

Ask arround the sailing community about how much one can be hurt by a
flailing synthetic rope - it might not be as bad as wire in some ways but
because it is infinately more flexible it can be just as bad.

"Bob Johnson" wrote in message
...
Hi Bill --

After my limited experience with it, I can't help but think that
synthetic is going to be a lot safer and less nasty to work with during
breaks or whenever else it has to be dodged or handled. It's light as a
feather, soft as a baby's butt and stores absolutely no energy.

BJ

"W.J. (Bill) Dean (U.K.)." wrote:

A winch should never have any doors or windows open while actually
launching. The cab must be fully enclosed, doors and windows shut.
The
windows must be of laminated glass or similar, with Lexan or something
similar on the inside surfaces. Any openings not glazed must be
protected
with expanded metal sheet, weldmesh or similar.

If the cable breaks, and sooner or later it will, it can get inside the
winch through any opening with amazing ferocity.

One of the Long Mynd amateur winch drivers had the back window slightly
open. The cable broke, came in through the window and attacked his
clothing. He considered he had a very lucky escape, and has given up
driving the winch.

At another club one of the most experienced of all winch drivers parked
his
car directly behind the winch and facing it, what he thought was a safe
distance away. This was at a busy club which has done many thousands
of
winch launches every year for a very long time. The cable broke and
flew
back, trashing the back of his car and round the car to break one of the
front door windows. I saw the car afterwards and asked who had run
into
him.

This sort of thing does not happen very often so it takes people by
surprise. It is a completely avoidable risk and is just not worth
taking.

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


"Martin Gregorie" wrote in message
...

snip

Climate control: there is a diesel burning heater for winter and the
sliding doors open in summer.

Martin Gregorie