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#151
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SAFE Winch Launching and automatic gearboxes
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 |
#152
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SAFE Winch Launching and automatic gearboxes
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. |
#153
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SAFE Winch Launching and automatic gearboxes
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 |
#154
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SAFE Winch Launching and automatic gearboxes
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. |
#155
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SAFE Winch Launching and automatic gearboxes
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. |
#156
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SAFE Winch Launching and automatic gearboxes
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 |
#157
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SAFE Winch Launching and automatic gearboxes
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 |
#158
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SAFE Winch Launching and automatic gearboxes
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. |
#159
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SAFE Winch Launching and automatic gearboxes
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. |
#160
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SAFE Winch Launching and automatic gearboxes
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. |
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