SAFE Winch Launching

At 00:10 24 July 2009, bildan wrote:
On Jul 21, 4:12=A0pm, tommytoyz wrote:
Perhaps the way to go is just buy a good used winch from a European
club. What was the offered price again for that old Tost winch at
Lasham?

My German contacts recommend against buying an old Tost winch since
the parts they are made from are no longer available. In many ways
they share the same technology as the old Gerhleins.

Tost winches are good solid bits of German engineering and, from what I
can gather, far superior to a Gerhlein. The Lasham ones did over 7,500
launches each per year from 1985 to 2008, and one of them is still going
strong at the Mendips Gliding Club, who are apparently delighted with it.
Lasham has retained the other one for the time being.

The only downsides are that they are purely manually driven and a bit
fiddly to operate, and that some spares are getting difficult to obtain.
They can be fitted with the Skylaunch throttle kits which overcomes the
first problem.

Derek Copeland

I assume that Bill's comment is intended to be yet another thinly veiled
attack on Skylaunch, who make an excellent winch! There is no hard
evidence that rollers are any less Dyneema friendly, and in any case
Skylaunch can supply and fit swivelling pulleys if you think they are
better. Our new Skylaunch winches at Lasham are so fitted.

Again the rollers he is talking about are as fitted to antiquated US
Gerhlein winches, and his Ford Model T analogy is about right.

The guillotine issue is more relevant. For some reason hardened steel
blades that will chop steel cable many times are instantly blunted when
used on any type of UHMWPE synthetic cable. I believe the fix is to
replace the anvil with a bronze component. So much for modern materials
and technology!

Derek Copeland

At 23:39 23 July 2009, bildan wrote:
On Jul 23, 12:45=A0am, Derek Copeland wrote:
Chris,

Nothing special required, except that the rollers or pulleys should be
smoothed out and polished if they have been used for steel cable. Some
types of drum may need to be reinforced as Dyneema can slip and
tighten
o=
n
the drum to the extent that it get crushed.


More spectacularly bad advice from Del C.

Smoothing and polishing rollers will NOT work since the rope slides in
a helical path on the roller if the wrap angle is not exactly at right
angles to the roller. All roller designs used with 'plastic rope'
show rings of melted plastic when used with Plasma Rope. The rope
itself shows severe damage from melting. Using rollers with Plasma
Rope is an expensive mistake

Plasma Rope (Spectra/Dyneema) should have swiveling pulleys with
specific pulley groove geometry. I have a tested design for fairlead
pulleys with a Plasma specific guillotine that I'll let anybody use to
make their own. E-mail me and I'll send the drawings.

bildan wrote:
On Jul 21, 4:12 pm, tommytoyz wrote:
Perhaps the way to go is just buy a good used winch from a European
club. What was the offered price again for that old Tost winch at
Lasham?

My German contacts recommend against buying an old Tost winch since
the parts they are made from are no longer available.
...

This is not true. All parts are available, see
http://tost-startwinden.de/ or contact Tost .

There are a few hundred Tost winches operating here in Germany, and
other countries, and I have heard of no difficulties getting spare
parts, or even drawings if required.

--
Peter Scholz
ASW 24 JEB

At 07:04 24 July 2009, Peter Scholz wrote:
bildan wrote:
On Jul 21, 4:12 pm, tommytoyz wrote:
Perhaps the way to go is just buy a good used winch from a European
club. What was the offered price again for that old Tost winch at
Lasham?

My German contacts recommend against buying an old Tost winch since
the parts they are made from are no longer available.
...

This is not true. All parts are available, see
http://tost-startwinden.de/ or contact Tost .

There are a few hundred Tost winches operating here in Germany, and
other countries, and I have heard of no difficulties getting spare
parts, or even drawings if required.

--
Don't worry Peter! Bill thinks that anything not made in the USA is no
good. He is from the country that came up with the supposedly self
defending B17 Bomber that your lot shot down in droves in WW2, at least
until the long range Mustang fighters with UK designed Merlin engines came
along to defend them.

Then there are their awful, gas guzzling automobiles with stone age
technology and built in obsolescence. No wonder that the US Citizens who
can afford them buy German and Japanese cars.

I will make an exception for the Chevy big block V8 engines which seem to
be strong and reliable. Ditto the Buick V8.

Most US 'inventions' have British or German origins, including
Automobiles, Jet Engines, Supersonic Aircraft, Rockets, Harrier Jump Jets,
Gliders, etc, etc.

I note that even the Gehrlein (Gerhlein?) Winch seems to have a German
type name, so maybe it's not as bad as I thought. Does anyone have any
information about this company?

Derek Copeland

P.S. To answer Tommytoyz's question, I believe the Tost winch we sold as
a basic unit fetched about £8,500 (10,000 Euros, 14,000 US Dollars). Not
bad for something that cost about £20,000 new in 1985.

Del C wrote:
I note that even the Gehrlein (Gerhlein?) Winch seems to have a German
type name, so maybe it's not as bad as I thought. Does anyone have any
information about this company?

Derek Copeland

Gehrlein Winches were built by Gehrlein Welding of Erie, Pennsylvania,
which was run by Larry Gehrlein and Larry Gehrlein, Jr., both involved
in soaring in the 1950's and until their deaths a few years ago.
Rod and Jay Gehrlein, sons of Larry Sr. operate Gehrlein Products a
glider repair facility, near Erie, and fly their gliders out of their
strip behind the repair shop.

Hello All

Has there been any experimentation with a payout winch similar to what
is used for hang glider launches.
It seems that the acceleration on takeoff would be similar to aero
tow.
A drum, tension feedback, and rewind unit in the back of a full size
pickup truck..

Rodger Reinhart

On Jul 24, 10:58*am, Rodger wrote:
Hello All

Has there been any experimentation with a payout winch similar to what
is used for hang glider launches.
It seems that the acceleration on takeoff would be similar to aero
tow.
A drum, tension feedback, and rewind unit in the back of a full size
pickup truck..

Rodger Reinhart

http://video.google.com/videoplay?do...68343289&hl=en

and http://video.google.com/videoplay?do...80774460&hl=en

and http://www.nwskysports.com/videos/winch%20launch.mov

On Jul 24, 1:04*am, Peter Scholz
wrote:
bildan wrote:
On Jul 21, 4:12 pm, tommytoyz wrote:
Perhaps the way to go is just buy a good used winch from a European
club. What was the offered price again for that old Tost winch at
Lasham?

My German contacts recommend against buying an old Tost winch since
the parts they are made from are no longer available. *
...

This is not true. All parts are available, seehttp://tost-startwinden.de/or contact Tost .

There are a few hundred Tost winches operating here in Germany, and
other countries, and I have heard of no difficulties getting spare
parts, or even drawings if required.

--
Peter Scholz
ASW 24 JEB

I am familiar with the Tost winch site. What they specifically say is
this:

"There are more than 5000 items available in our warehouse. Most of
the spare parts for our launching winches, from the year of
manufacture 1980 up, are in stock constantly. If nevertheless a spare
part is not available at once we'll do everything in order to get it
for you or to manufacture it, if possible."

Most of the old Tost winches were built before 1980 (Some from the
1950's) using a modified fully floating axle from a German Army
truck. I'm told the axle and parts for it are very difficult to get
and expensive when you can find them.

However, I'm not the definitive source. I'd suggest contacting
someone in Germany for an independent, informed opinion before buying
one.

On Jul 24, 12:30*am, Derek Copeland wrote:
I assume that Bill's comment is intended to be yet another thinly veiled
attack on Skylaunch, who make an excellent winch! There is no hard
evidence that rollers are any less Dyneema friendly, and in any case
Skylaunch can supply and fit swivelling pulleys if you think they are
better. Our new Skylaunch winches at Lasham are so fitted.

Again the rollers he is talking about are as fitted to antiquated US
Gerhlein winches, and his Ford Model T analogy is about right.

The guillotine issue is more relevant. For some reason hardened steel
blades that will chop steel cable many times are instantly blunted when
used on any type of UHMWPE synthetic cable. I believe the fix is to
replace the anvil with a bronze component. So much for modern materials
and technology!

Derek Copeland

At 23:39 23 July 2009, bildan wrote:

On Jul 23, 12:45=A0am, Derek Copeland *wrote:
Chris,

Nothing special required, except that the rollers or pulleys should be
smoothed out and polished if they have been used for steel cable. Some
types of drum may need to be reinforced as Dyneema can slip and
tighten
o=
n
the drum to the extent that it get crushed.

More spectacularly bad advice from Del C.

Smoothing and polishing rollers will NOT work since the rope slides in
a helical path on the roller if the wrap angle is not exactly at right
angles to the roller. *All roller designs used with 'plastic rope'
show rings of melted plastic when used with Plasma Rope. *The rope
itself shows severe damage from melting. *Using rollers with Plasma
Rope is an expensive mistake

Plasma Rope (Spectra/Dyneema) should have swiveling pulleys with
specific pulley groove geometry. *I have a tested design for fairlead
pulleys with a Plasma specific guillotine that I'll let anybody use to
make their own. *E-mail me and I'll send the drawings.

It wasn't meant to be 'thinly veiled'.

Actually Derek's inexperience is showing. There is a difference
between guillotines for steel and Spectra/Dyneema in that the shearing
cutters used with steel won't cut "plastic rope". It doesn't 'blunt'
the blade, it just pushes them apart and defeats the cutting attempt.
Spectra/Dyneema is a lot tougher than steel.

You need a more aggressive guillotine with a "chopping" action that
forces a sharp steel blade against an anvil instead of a shearing
action. A steel edge cutting against a brass block works well as does
a plastic block which saves the edge.

Bill,

I must admit that I have only ever seen one guillotine in pieces to carry
out the modification, and that was for a Tost winch when when we carried
out trials on UHMWPE synthetic cable. This is a spring loaded system in a
tube, activated by a lever in the cab pulling out a pin via a Bowden
cable. The steel fixed bottom element was replaced by a bronze equivalent
and that was it.

I should point out that our winches are maintained by professional staff
at Lasham, so I don't get much involved in that side of things. I am an
amateur gliding instructor and a winch driver, with 28 years of wire
launching experience.

Have you ever driven or had a launch on a Skylaunch winch? No, I thought
not! I think that you would be impressed if you did. It is easy to drive
and gives smooth, consistent and correctly speeded launches, unlike
anything I had launched on before. If it as bad as you keep claiming, why
have so many major European gliding clubs bought them, often in preference
to their own National products?

Usual disclaimers. I have no financial or other connections to Skylaunch,
other than being a satisfied user of their products.

Derek Copeland


At 19:38 24 July 2009, bildan wrote:
On Jul 24, 12:30=A0am, Derek Copeland wrote:
I assume that Bill's comment is intended to be yet another thinly
veiled
attack on Skylaunch, who make an excellent winch! There is no hard
evidence that rollers are any less Dyneema friendly, and in any case
Skylaunch can supply and fit swivelling pulleys if you think they are
better. Our new Skylaunch winches at Lasham are so fitted.

Again the rollers he is talking about are as fitted to antiquated US
Gerhlein winches, and his Ford Model T analogy is about right.

The guillotine issue is more relevant. For some reason hardened steel
blades that will chop steel cable many times are instantly blunted
when
used on any type of UHMWPE synthetic cable. I believe the fix is to
replace the anvil with a bronze component. So much for modern
materials
and technology!

Derek Copeland

At 23:39 23 July 2009, bildan wrote:

On Jul 23, 12:45=3DA0am, Derek Copeland =A0wrote:
Chris,

Nothing special required, except that the rollers or pulleys should
be
smoothed out and polished if they have been used for steel cable.
Some
types of drum may need to be reinforced as Dyneema can slip and
tighten
o=3D
n
the drum to the extent that it get crushed.

More spectacularly bad advice from Del C.

Smoothing and polishing rollers will NOT work since the rope slides
in
a helical path on the roller if the wrap angle is not exactly at
right
angles to the roller. =A0All roller designs used with 'plastic
rope'
show rings of melted plastic when used with Plasma Rope. =A0The rope
itself shows severe damage from melting. =A0Using rollers with Plasma
Rope is an expensive mistake

Plasma Rope (Spectra/Dyneema) should have swiveling pulleys with
specific pulley groove geometry. =A0I have a tested design for
fairlead
pulleys with a Plasma specific guillotine that I'll let anybody use
to
make their own. =A0E-mail me and I'll send the drawings.

It wasn't meant to be 'thinly veiled'.

Actually Derek's inexperience is showing. There is a difference
between guillotines for steel and Spectra/Dyneema in that the shearing
cutters used with steel won't cut "plastic rope". It doesn't
'blunt'
the blade, it just pushes them apart and defeats the cutting attempt.
Spectra/Dyneema is a lot tougher than steel.

You need a more aggressive guillotine with a "chopping" action that
forces a sharp steel blade against an anvil instead of a shearing
action. A steel edge cutting against a brass block works well as does
a plastic block which saves the edge.