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#61
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what every boy needs - yeah seriously
On Jan 14, 6:39*am, "
wrote: * The shop I started at had no form of electric welder! * -------------------------------------------------------------------------------- You don't REALLY need a REAL buzz box. Three 12v batteries will do the trick, which is to dump about one volcano's-worth of HEAT into the opposite sides of the seat. Molton steel. It has GOT to shrink as it cools. And when it does, it shrinks the seat as well. So with a bead at the top and a bead at the bottom, hit the thing with a cup of ice water, it shrinks into an OVAL and you can pop it right outta there. -Bob |
#62
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what every boy needs - yeah seriously
On Jan 14, 11:10*am, "Peter Dohm" wrote:
wrote in message ... On Jan 13, 10:06 pm, "Peter Dohm" wrote: At the obvious cost of proving myself a heretic regarding VWs.... We could go back into the old debate about whether a nearly stock VW engine could be a reliable 50 to 60hp powerplant with the right sort of pressure cooling system. With all due respect to Bob, a/k/a Veeduber, I am still convinced that it can ---------------------------------------------------------------------------------------- Mybe it CAN. All I'm saying is that it never happened for me and I gave it a pretty good go. Failures ALWAYS pointed to excessive heating/lack of cooling. Probably the biggest factor in folks thinking it CAN do that are the ones that simply ran it til it dropped then built another, without paying any attention to MTBO. I know two turbo types that thought TEN HOURS was a good number for their heads. One of those guys swore up & down that he NEVER HAD A LICK OF TROUBLE during a thousand hours behind a turbo'd VW. But what he failed to mention was that those thousand hours were accumulated on THREE DIFFERENT CRANKCASES and that about the only time you saw his plane was at a fly-in or TORN DOWN, getting new heads, new bearings, a new crankshaft, and so forth. But he's right: It NEVER LET HIM DOWN. He never crashed. He never had to land off-field (although he had a number of landings at strange airports). And if he had to rent a U-Haul truck to get the thing back home, why, that was just part of the game. (KR2, based in Oregon) I don't look at flying that way. |
#63
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what every boy needs - yeah seriously
wrote in message ... On Jan 14, 11:10 am, "Peter Dohm" wrote: wrote in message ... On Jan 13, 10:06 pm, "Peter Dohm" wrote: At the obvious cost of proving myself a heretic regarding VWs.... We could go back into the old debate about whether a nearly stock VW engine could be a reliable 50 to 60hp powerplant with the right sort of pressure cooling system. With all due respect to Bob, a/k/a Veeduber, I am still convinced that it can ---------------------------------------------------------------------------------------- Mybe it CAN. All I'm saying is that it never happened for me and I gave it a pretty good go. Failures ALWAYS pointed to excessive heating/lack of cooling. Probably the biggest factor in folks thinking it CAN do that are the ones that simply ran it til it dropped then built another, without paying any attention to MTBO. I know two turbo types that thought TEN HOURS was a good number for their heads. One of those guys swore up & down that he NEVER HAD A LICK OF TROUBLE during a thousand hours behind a turbo'd VW. But what he failed to mention was that those thousand hours were accumulated on THREE DIFFERENT CRANKCASES and that about the only time you saw his plane was at a fly-in or TORN DOWN, getting new heads, new bearings, a new crankshaft, and so forth. But he's right: It NEVER LET HIM DOWN. He never crashed. He never had to land off-field (although he had a number of landings at strange airports). And if he had to rent a U-Haul truck to get the thing back home, why, that was just part of the game. (KR2, based in Oregon) I don't look at flying that way. -----------begin new post--------- I am really not dissagreeing with you--as the pressure system that I am thinking of would use a VW type cooling fan to augment the ram air pressure. That would be a rather obvious source of added weight and an easily visible use of power--and would never be popular. Interestingly, the guys I knew who broke cranks (amoung other interesting problems) were also flying KR2s--although they were based in Florida. Personally, that is not a level of reliability that I could accept; and I have never considered an application that I believed would draw much more than 40 HP continuously from a VW--even though I have been willing to consider ideas that asserted a theoretical peak power of 60 HP. |
#64
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what every boy needs - yeah seriously
Peter Dohm wrote:
wrote in message ... On Jan 14, 11:10 am, "Peter Dohm" wrote: wrote in message ... On Jan 13, 10:06 pm, "Peter Dohm" wrote: At the obvious cost of proving myself a heretic regarding VWs.... We could go back into the old debate about whether a nearly stock VW engine could be a reliable 50 to 60hp powerplant with the right sort of pressure cooling system. With all due respect to Bob, a/k/a Veeduber, I am still convinced that it can ---------------------------------------------------------------------------------------- Mybe it CAN. All I'm saying is that it never happened for me and I gave it a pretty good go. Failures ALWAYS pointed to excessive heating/lack of cooling. Probably the biggest factor in folks thinking it CAN do that are the ones that simply ran it til it dropped then built another, without paying any attention to MTBO. I know two turbo types that thought TEN HOURS was a good number for their heads. One of those guys swore up & down that he NEVER HAD A LICK OF TROUBLE during a thousand hours behind a turbo'd VW. But what he failed to mention was that those thousand hours were accumulated on THREE DIFFERENT CRANKCASES and that about the only time you saw his plane was at a fly-in or TORN DOWN, getting new heads, new bearings, a new crankshaft, and so forth. But he's right: It NEVER LET HIM DOWN. He never crashed. He never had to land off-field (although he had a number of landings at strange airports). And if he had to rent a U-Haul truck to get the thing back home, why, that was just part of the game. (KR2, based in Oregon) I don't look at flying that way. -----------begin new post--------- I am really not dissagreeing with you--as the pressure system that I am thinking of would use a VW type cooling fan to augment the ram air pressure. That would be a rather obvious source of added weight and an easily visible use of power--and would never be popular. Interestingly, the guys I knew who broke cranks (amoung other interesting problems) were also flying KR2s--although they were based in Florida. Personally, that is not a level of reliability that I could accept; and I have never considered an application that I believed would draw much more than 40 HP continuously from a VW--even though I have been willing to consider ideas that asserted a theoretical peak power of 60 HP. I've always thought that the broken cranks were the cast versions not forged cranks. I've never heard of anyone breaking a forged crank. FWIW Richard |
#65
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what every boy needs - yeah seriously
On Jan 14, 1:10*pm, "Peter Dohm" wrote:
Interesting. *I did not know that the 8 valve VW was lighter than the Type IV, especially since I believed that it probably had an iron block. Peter They are iron blocks, just really nice and thin. But tough. Burn about 3 gal per hour (18 mpg @55mph) wide open throttle going up the hills around here in 3rd/4th gear which works out to around 55 Hp? Not all that much but it never would over heat and 250K+ miles is quite common. The kids with turbos still didn't have cooling problems and they are probably a lot closer to the factory 100 or so HP claim. The 2.0L version with the cross flow head would probably package the best. I've got one on an engine stand that I was going to put in a Q2. Decided I don't like Q2's. Still have the PSRU sprokets and a turbo sitting on the motor.............Got to get rid of some of my junk. ================ Leon McAtee |
#66
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what every boy needs - yeah seriously
wrote in message ... On Jan 12, 9:53 pm, "Maxwell" #$$9#@%%%.^^^ wrote: wrote in message Casting your own VW head can be done, but it's not nearly as easy as you would like to suggest. If you have examples to the contrary, as I said before, I'm not the only one on this news group that would love to see them. As I said it it depends on your definition of easy. Sounds to me like your one of those builders that is best sticking to a quick build RV with a FWF package since everything has been already worked out. Independent and creative thought apparently is a challenge for you. If an RV is in fact the path you have chosen my condolences go out to Mr. VanGrusvens customer service staff. ======================= Nice smoke screen, but hardly related to the discussion at hand. You insist there are easy ways to cast a head with cooling fins using lost wax or lost foam, but you still can't provide any examples. |
#67
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what every boy needs - yeah seriously
On Jan 14, 4:55*pm, "Peter Dohm" wrote:
I am really not dissagreeing with you--as the pressure system that I am thinking of would use a VW type cooling fan to augment the ram air pressure. That would be a rather obvious source of added weight and an easily visible use of power--and would never be popular. ------------------------------------------------------------------------------ The trouble with the coaxial blower mods was the SAME as with the turbo people, in that there simply was not enough fin area for the increased density/flow to do much good. Everyone seemed determine to get "60hp" sixty mythical horsepower from an engine that in its most powerful configuration only produced 57bhp @ 4400rpm.... and you only got to pull that for something less than 5 minutes. So you increase the displacement to something seriously silly and USING THE SAME HEADS & FIN AREA start pulling as much as 85hp(!!) from that configuration... and wondering why things weren't working right. Maximum SUSTAINABLE OUTPUT of the '1600' (displacement 1584cc) under Standard Day conditions was something like 36bhp, whereas PEAK OUTPUT can be just about anything you're willing to pay for. It doesn't blow up (although it can) but it blows your bhp right into the porcelain fixture. -------------------------------------------------------------------------------------------- Interestingly, the guys I knew who broke cranks (amoung other interesting problems) were also flying KR2s--although they were based in Florida. ---------------------------------------------------------------------------------------------- When you talk 'broken cranks' and VW's you gotta define which TYPE of 'broken crankshaft' you're referring to, because there are TWO distinct cases. In the FIRST CASE, ANY VW crankshaft, cast, forged or billet,....can, will and has... displayed the 'classic' fracture failure, in which a fracture is initiated in one of the internal threads of the PULLEY HUB, the peaks of which may approach to within . 058" of one of the corners of the Woodruff Key keyway cut into the NOSE of the crankshaft. (As you may know, the Woodruff Key is a segment of a circle, as is it's keyway. Unlike a SQUARE key, with the Woodruff, which is far easier to fabricate, if you want a KEY of substantial length and width then you must be willing to accept a KEYWAY of significant DEPTH. This is what allows the keyway to approach so closely to the internal threads. Another factor here is that, unlike British or American thread-forms, METRIC threads come to a sharp POINT. These factors COMBINE to virtually guarantee the formation of a crack in the nose of the crankshaft.) The crack then progresses along the corner of the Woodruff keyway cut until it crosses over to the Stress Relief groove which completely encircles the nose of the crankshaft. Once it reaches that point you may as well tighten your straps and punch the locator beacon because you're about to turn into a glider. This situation was discovered by the British firm of Ardem who sought -- and RECEIVED -- certification for the Converted VW. They worked out the critical load was something on the order of 27 bhp, and the maximum amount of time was around 200 hours. And that's what they got certification for. T.O. power limited to 3 minutes; tear-down & magnaflux inspection REQUIRED at 200 hours. Once they got all the paperwork out of the way they even allowed Prince Phillip to hop one (ie, license-built Druine 'Turbulent' powered by the Ardem 4C02, a VW engine converted for flight that was rated at 30.7bhp @ 3000 rpm (but only for about one minute). Then we have the Clyde's Buggy sand-cast crankshafts. Clyde's (sp?) is better known today as 'CB Performance' but it's the same shop just a different name. I believe Clyde's last name is Tomlinson but I'm going back forty years and more... Anyway, the owner's son went to Brazil and began importing all sorts of stuff, including crankshafts. Rex Taylor used some of those crankshafts -- which happened to be castings -- in some of his engines and their failure effectively put Rex out of business. But it also fostered the Conventional Wisdom that ALL cast crankshafts were bad. Which is kinda strange when you think of it because the Big Three have been using cast cranks in their biggest engines since Jeeter was a pup. In fact, what you're running into here is the fact that a crankshaft fabricated using the Lost Foam process is actually superior to a forging, which is why you find cast cranks in some of the best racing engines. But Volkswagen owners didn't get the benefit of those properly cast cranks until they started coming in from China. Prior to then we had some cast cranks that were so bad the thing could shatter if it fell off the bench. The reason a MODERN casting is superior to a forging has to do with the manner in which the casting is allowed to cool. A modern-day lost- foam CAST CRANKSHAFT is allowed to cool at a carefully controlled rate so that the internal grain structure of the crank comes out denser than in a forging. Another advantage is that many of the high- strength alloys simply cannot be forged! But one of the funniest things you'll hear about cast cranks is that they are LESS EXPENSIVE. Due to the price of today's fuels it actually costs MORE to produce a a high-quality cast crankshaft. Using casting methods, you CAN produce a cheap crank but the real reason to go with a casting is to take advantage of the casting's denser grain structure. Those early cast cranks were junk, pure and simple. Dropping one could cause it to break like a piece of glass and using one in an airplane engine was little more than corporate suicide. There is simply no way you can compare those early sand-cast crankshafts with a modern-day casting, such as used by Volkswagen and Ford. Most American pilots aren't familiar with the 'flying club' system found in Europe and most other places in the world. One reason the clubs enjoy an enviable safety record is because they are required to have a certified A&E on staff. aren't aware of is that flying clubs are REQUIRED to have a certified A&E on staff. Which brings up an interesting point about VW engines converted for flight. A majority of those engines were used to power flying club hacks, with a long waiting list that covered the entire flying season. Remember the tear-down and inspection requirement for the Ardem engines? Specifically that bit about a Magnaflux inspection every two hundred hours? The truth is, a Magnaflux inspection cost MORE than a new crankshaft. As soon as the airplane was taken off flying status and began to undergo is winter maintenance schedules, the engine was torn down in order to receive a NEW crankshaft. Depending on how many hours the flying club's planes accumulated over the summer, you could count on it having a NEW crankshaft every two years. With that in mind it's easy to see why broken crankshafts simply were not an issue with any of the club's VW powered aircraft. -R.S.Hoover |
#68
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what every boy needs - yeah seriously
wrote in message ... On Jan 14, 4:55 pm, "Peter Dohm" wrote: I am really not dissagreeing with you--as the pressure system that I am thinking of would use a VW type cooling fan to augment the ram air pressure. That would be a rather obvious source of added weight and an easily visible use of power--and would never be popular. ---------------------------------------------------------------------- -------- The trouble with the coaxial blower mods was the SAME as with the turbo people, in that there simply was not enough fin area for the increased density/flow to do much good. Everyone seemed determine to get "60hp" sixty mythical horsepower from an engine that in its most powerful configuration only produced 57bhp @ 4400rpm.... and you only got to pull that for something less than 5 minutes. So you increase the displacement to something seriously silly and USING THE SAME HEADS & FIN AREA start pulling as much as 85hp(!!) from that configuration... and wondering why things weren't working right. Maximum SUSTAINABLE OUTPUT of the '1600' (displacement 1584cc) under Standard Day conditions was something like 36bhp, whereas PEAK OUTPUT can be just about anything you're willing to pay for. It doesn't blow up (although it can) but it blows your bhp right into the porcelain fixture. SNIP -R.S.Hoover Hope you don't mind my jumping in here Bob. Do you remember the Porsche engine with the cooling fan behind the prop? It was supposed to eliminate the need for cowl flaps and also prevent shock cooling too. What happened to it? -- Anyolmouse |
#69
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what every boy needs - yeah seriously
fan-cooled VW/Porsche http://popnet.ch/reichen/HB207/image035.htm
it's the powerplant of a ALFA HB 207, quite a few flying here in Europe http://popnet.ch/reichen/HB207/index.htm "Anyolmouse" schrieb im Newsbeitrag ... wrote in message ... On Jan 14, 4:55 pm, "Peter Dohm" wrote: I am really not dissagreeing with you--as the pressure system that I am thinking of would use a VW type cooling fan to augment the ram air pressure. That would be a rather obvious source of added weight and an easily visible use of power--and would never be popular. ---------------------------------------------------------------------- -------- The trouble with the coaxial blower mods was the SAME as with the turbo people, in that there simply was not enough fin area for the increased density/flow to do much good. Everyone seemed determine to get "60hp" sixty mythical horsepower from an engine that in its most powerful configuration only produced 57bhp @ 4400rpm.... and you only got to pull that for something less than 5 minutes. So you increase the displacement to something seriously silly and USING THE SAME HEADS & FIN AREA start pulling as much as 85hp(!!) from that configuration... and wondering why things weren't working right. Maximum SUSTAINABLE OUTPUT of the '1600' (displacement 1584cc) under Standard Day conditions was something like 36bhp, whereas PEAK OUTPUT can be just about anything you're willing to pay for. It doesn't blow up (although it can) but it blows your bhp right into the porcelain fixture. SNIP -R.S.Hoover Hope you don't mind my jumping in here Bob. Do you remember the Porsche engine with the cooling fan behind the prop? It was supposed to eliminate the need for cowl flaps and also prevent shock cooling too. What happened to it? -- Anyolmouse |
#70
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what every boy needs - yeah seriously
"oilsardine" wrote in message ... : fan-cooled VW/Porsche http://popnet.ch/reichen/HB207/image035.htm : : it's the powerplant of a ALFA HB 207, quite a few flying here in Europe : http://popnet.ch/reichen/HB207/index.htm : : : "Anyolmouse" schrieb im Newsbeitrag : ... : : wrote in message : ... : On Jan 14, 4:55 pm, "Peter Dohm" wrote: : : I am really not dissagreeing with you--as the pressure system that I : am : thinking of would use a VW type cooling fan to augment the ram air : pressure. : That would be a rather obvious source of added weight and an easily : visible : use of power--and would never be popular. : --------------------------------------------------------------------- - : -------- : : The trouble with the coaxial blower mods was the SAME as with the : turbo people, in that there simply was not enough fin area for the : increased density/flow to do much good. Everyone seemed determine to : get "60hp" sixty mythical horsepower from an engine that in its most : powerful configuration only produced 57bhp @ 4400rpm.... and you only : got to pull that for something less than 5 minutes. : : So you increase the displacement to something seriously silly and : USING THE SAME HEADS & FIN AREA start pulling as much as 85hp(!!) from : that configuration... and wondering why things weren't working right. : : Maximum SUSTAINABLE OUTPUT of the '1600' (displacement 1584cc) under : Standard Day conditions was something like 36bhp, whereas PEAK OUTPUT : can be just about anything you're willing to pay for. It doesn't blow : up (although it can) but it blows your bhp right into the porcelain : fixture. : SNIP : -R.S.Hoover : : Hope you don't mind my jumping in here Bob. Do you remember the Porsche : engine with the cooling fan behind the prop? It was supposed to : eliminate the need for cowl flaps and also prevent shock cooling too. : What happened to it? : : -- : Anyolmouse : Nice site. It isn't the same configuration as the one I saw in a magazine here in the US though. There was a large air intake filled with a fan just behind the prop. The fan was supposed to supply all the cooling needed and protect the engine from over cooling from ram air as well as supply cooling during taxi and low speed operation. -- Anyolmouse |
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