---------------------------------------------------------- Zenith-List Digest Archive --- Total Messages Posted Sat 02/25/06: 16 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:41 AM - Re: Aux fuel pump in 701. (Tim & Diane Shankland) 2. 10:42 AM - Re: Aux fuel pump in 701.Aux fuel pump in 701. (Larry Bohannon) 3. 11:56 AM - Re: Aux fuel pump in 701.Aux fuel pump in 701. (Jeff Davidson) 4. 12:15 PM - Questions About Bending Brake (William Dominguez) 5. 12:52 PM - RE : Questions About Bending Brake (Carlos Sa) 6. 02:12 PM - Re: RE : Questions About Bending Brake (William Dominguez) 7. 02:29 PM - Re: RE : Questions About Bending Brake (Zodie Rocket) 8. 03:03 PM - Re: Aux fuel pump in 701.Aux fuel pump in 701. (Bryan Martin) 9. 03:14 PM - Re: Questions About Bending Brake (Ron Lendon) 10. 03:29 PM - Re: Aux fuel pump in 701. (nyterminat@aol.com) 11. 03:33 PM - Re: Aux fuel pump in 701. (nyterminat@aol.com) 12. 05:11 PM - RE : Re: RE : Questions About Bending Brake (Carlos Sa) 13. 07:08 PM - O-200 engine bolts hardware (Brian Briggerman) 14. 07:14 PM - Re: O-200 engine bolts hardware (Gdascomb@aol.com) 15. 07:24 PM - Re: Aux fuel pump in 701. (Gary Gower) 16. 08:16 PM - Re: Aux fuel pump in 701.Aux fuel pump in 701. (ruruny@aol.com) ________________________________ Message 1 _____________________________________ Time: 10:41:44 AM PST US From: Tim & Diane Shankland Subject: Re: Zenith-List: Aux fuel pump in 701. --> Zenith-List message posted by: Tim & Diane Shankland No, because if have two vents one in each wing, on the bottom recessed, similar to a Grumman Cheetah. Tim Craig Payne wrote: >--> Zenith-List message posted by: "Craig Payne" > >Wouldn't connecting the two vents create a single point of failure? > >-- Craig > > > > > > > > > ________________________________ Message 2 _____________________________________ Time: 10:42:17 AM PST US From: "Larry Bohannon" Subject: Re: Zenith-List: Aux fuel pump in 701.Aux fuel pump in 701. --> Zenith-List message posted by: "Larry Bohannon" I was planning on installing the fuel system in my 701 as per plans. Now, with all the talk of pumps,filters,ram air tubes in the stock vented gas caps, and uneven flow from one tank or the other, I'm wondering what to do. The plans have only the stock vented gas cap,a finger screen fitting at the exit of the tank,the two hoses joining at the stock gascolator which is mounted to the left of centerline at the low point of the fuselage and a single hose running under the pilots seat to a single shutoff valve at the pilots feet and then on to the engine. Has anyone flown with this per plans setup for any length of time?? When I saw Roger's 701 I noticed there appeared to be some clear filters in the lines where they entered the baggage compartment and he had ram air tubes in the gas caps on top of the wings. I don't know how the rest of Roger's system is set up but even Zenith's own plane is not per their own plans!! What gives?? If we were to build it from the plans would this be unsafe? The reason I bought the supposedly "complete" kit and plans was that someone with the know how ( Chris H. and Zenith) had already figured all this stuff out, but I saw in the Zenith newsletter about a year or so ago, where Chris was giving info and a drawing of how to put the ram air tube in the gas caps but there is nothing in the actual plans. How are we to know what to do and what is safe if Zenith doesn't even follow their own plans? Also, is anybody using the black rubber hose that came with the kit? I seem to recall reading somwhere the rubber hose breaks down inside and the pieces clog the carbs? I'm almost finished with my 701 airframe and I will be installing the engine and fuel system as soon as I receive the FWF kit I ordered from Skyshop. i read where the biggest cause of accidents in homebuilts is the fuel system. I only have a high school education but I can build according to plans, if the plans are correct and safe, but can anybody tell me if the plans are correct and safe or not? Should I follow the plans exactly, even if Zenith doesn't, or should I modify? Any help/advice from the list would be greatly appreciated. Larry Bohannon Winder, Georgia ________________________________ Message 3 _____________________________________ Time: 11:56:41 AM PST US From: "Jeff Davidson" Subject: RE: Zenith-List: Aux fuel pump in 701.Aux fuel pump in 701. --> Zenith-List message posted by: "Jeff Davidson" Larry, On the question about "Also, is anybody using the black rubber hose that came with the kit?": I am going to use it on my 601 HD with leading edge tanks only. I modeled my fuel system after the XL system on 6K2 available on the ZAC web site. Yesterday, I took a good look at Jim Pellien's 601XL, which is certified as an LSA. It uses the rubber hose too. With the dual stick option, the hose runs right in front of the spar through the dual stick bracket to the Andair selector value in the console. FWIW, I have found that the builders have a lot of input from various sources, but that ZAC does not provide an exact fuel system design. Several for the 601 can be found on the ZAC web site. This is an experimental aircraft, so you have a lot of freedom/responsibility. For complete assurance, I suggest that you draw a diagram of your proposed system and send it to ZAC for comment and validation by Nick, Sebastian, Roger, Chris, or whoever else may answer. In my opinion, that is how you can get the confidence that comes with the designer's suggestions and approval on your particular system. Jeff Davidson ________________________________ Message 4 _____________________________________ Time: 12:15:53 PM PST US From: William Dominguez Subject: Zenith-List: Questions About Bending Brake --> Zenith-List message posted by: William Dominguez Does the material have to be flat before bending? Not twisted. Does ZAC 48 brake need welding? Can it be gas welded? What is the best way to cut .040 thick materials? Ive been experimenting with a wooden bending brake with mixed success. When I bend L angles of .040 and 40 long it comes out twisted and slightly bowed. The material is not flat and it is twisted before bending. I have the suspicion that the snips are causing this twisting in the material by stretching the border while cutting it. If the border is slightly larger than the center this may cause the twist and the bowing after the bending. My wooden brake is very solid and straight and I can't see any bowing or twisting of the brake while bending. William Dominguez Plansbuilt 601XL ________________________________ Message 5 _____________________________________ Time: 12:52:09 PM PST US From: Carlos Sa Subject: RE : Zenith-List: Questions About Bending Brake --> Zenith-List message posted by: Carlos Sa Hello, William I went through that phase myself. A wooden brake will work well only on thin stock. I eventualy found a welding shop that built the 4' bending brake for me. Actually, I made it longer so I could use it to bend the rudder spar. Money well spent. For the longer parts, I rent a bending brake from a shop nearby. Took me forever to find them, but again, it was worth it. The parts have a very professional appearence. The plans for the (48") brake can be found somewhere on http://ch601.org/ Happy building Carlos CH601-HD, plans --- William Dominguez a crit : > --> Zenith-List message posted by: William Dominguez > > Does the material have to be flat before bending? Not > twisted. > > Does ZAC 48 brake need welding? Can it be gas welded? > > What is the best way to cut .040 thick materials? > > Ive been experimenting with a wooden bending brake > with mixed success. When I bend L angles of .040 and > 40 long it comes out twisted and slightly bowed. The > material is not flat and it is twisted before bending. > I have the suspicion that the snips are causing this > twisting in the material by stretching the border > while cutting it. If the border is slightly larger > than the center this may cause the twist and the > bowing after the bending. My wooden brake is very > solid and straight and I can't see any bowing or > twisting of the brake while bending. > > > William Dominguez > Plansbuilt 601XL Lche-vitrine ou lche-cran ? magasinage.yahoo.ca ________________________________ Message 6 _____________________________________ Time: 02:12:31 PM PST US From: William Dominguez Subject: Re: RE : Zenith-List: Questions About Bending Brake --> Zenith-List message posted by: William Dominguez Carlos, Did the welding shop built the brake from ZAC plans or from the plans on http://ch601.org/. How much they charged you. Thank you, William Dominguez Plansbuilt 601XL --- Carlos Sa wrote: > --> Zenith-List message posted by: Carlos Sa > > > Hello, William > > > I went through that phase myself. > A wooden brake will work well only on thin stock. > I eventualy found a welding shop that built the 4' > bending brake for me. > Actually, I made it longer so I could use it to bend > the rudder spar. > Money well spent. > > For the longer parts, I rent a bending brake from a > shop nearby. > Took me forever to find them, but again, it was > worth it. > The parts have a very professional appearence. > > The plans for the (48") brake can be found somewhere > on http://ch601.org/ > > Happy building > > > Carlos > CH601-HD, plans > ________________________________ Message 7 _____________________________________ Time: 02:29:20 PM PST US From: "Zodie Rocket" Subject: RE: RE : Zenith-List: Questions About Bending Brake --> Zenith-List message posted by: "Zodie Rocket" I'm hoping to have a new set of plans on the www.ch601.org website next month. This break can be wielded with arc/mig or gas it is 54inches long and works well. SO far we have made 4 of them. Mark Townsend Alma, Ontario Zodiac 601XL C-GOXL, CH701 just started www.ch601.org / www.ch701.com / www.Osprey2.com -----Original Message----- From: owner-zenith-list-server@matronics.com [mailto:owner-zenith-list-server@matronics.com] On Behalf Of William Dominguez Sent: Saturday, February 25, 2006 5:08 PM Subject: Re: RE : Zenith-List: Questions About Bending Brake --> Zenith-List message posted by: William Dominguez Carlos, Did the welding shop built the brake from ZAC plans or from the plans on http://ch601.org/. How much they charged you. Thank you, William Dominguez Plansbuilt 601XL --- Carlos Sa wrote: > --> Zenith-List message posted by: Carlos Sa > > > Hello, William > > > I went through that phase myself. > A wooden brake will work well only on thin stock. > I eventualy found a welding shop that built the 4' > bending brake for me. > Actually, I made it longer so I could use it to bend > the rudder spar. > Money well spent. > > For the longer parts, I rent a bending brake from a > shop nearby. > Took me forever to find them, but again, it was > worth it. > The parts have a very professional appearence. > > The plans for the (48") brake can be found somewhere > on http://ch601.org/ > > Happy building > > > Carlos > CH601-HD, plans > -- -- ________________________________ Message 8 _____________________________________ Time: 03:03:43 PM PST US Subject: Re: Zenith-List: Aux fuel pump in 701.Aux fuel pump in 701. From: Bryan Martin --> Zenith-List message posted by: Bryan Martin If the two wing tanks have separate vents, there could be a difference in the pressure venting the tanks. All else being equal, this difference in pressure is what will cause the two tanks to feed fuel at different rates. To get some idea of how large this difference in pressure might be, you can calculate a couple of pressure differences that the airplane will normally encounter in flight. One of these pressure differences is the lift generated by the wing. The CH701 has a gross weight of 1100 pounds and a wing area of 122 square feet. So the lift generated in level flight is 1100lb/122sqft=9lb/sqft or about .063 psi. If we assume the pressure under the wing is the same as static pressure then the pressure on top is .063 psi less than static. Another pressure difference encountered in flight is the difference between the ambient pressure and the ram air pressure, or the dynamic pressure. From an airspeed calibration table I have, dynamic pressure at 90 mph is about .14 psi. These are both pretty small numbers. In the worst case, where one fuel tank cap has a ram air tube and the other one just has a vent hole, the maximum pressure difference between the two tanks should be about .14 psi + .063 psi = .203 psi. The fuel pressure at the bottom end of the fuel line from the tank is the sum of the head pressure of the fuel and the air pressure pushing down on the surface of the fuel. If one tank is draining faster than the other, is there some point where the difference in head pressure in the two tanks will balance out the difference in air pressure and cause the fuel to feed evenly? Gasoline weighs six pounds per gallon, there are about seven and a half gallons in a cubic foot which gives 45 pounds per cubic foot or .026 pounds per cubic inch. So the head pressure one inch below the surface of a tank of gasoline is about .026 psi. Dividing the worst case air pressure difference of .203 psi by .026 psi gives 7.8 inches of gasoline. So, when the level of fuel in the "high pressure" tank is about 8 inches lower than the other, both tanks should be feeding evenly. In reality, the air pressure difference between the two tanks should be a lot less than this example. Will the engine be sucking air from one tank before the other tank is empty? The bottom of the gas tank on the 701 is about three and a half feet above the floor of the cabin. You may empty one tank before the other but both tanks will be empty before you start sucking air. There may be 8 inches more fuel on one side than the other when you start sucking air but all of that fuel will be in the fuel line. How much fuel does 8 inches of fuel line hold? This is why most high wing Cessnas can operate with the fuel selector in the both position with no danger of draining one tank before the other. And, in my experience, even they don't drain fuel evenly from both tanks. On the other hand, it is possible for a low wing airplane to drain one tank dry and leave a significant quantity of fuel in the other, which is why you usually draw fuel out of only one tank at a time on most low wing aircraft. So to answer your question. Is the fuel system in the plans safe? I would say yes. The fuel system in the plans is probably about the simplest you can get. Can it be improved upon? Sure. The ram air tubes on the caps will prevent small amounts of fuel from dribbling out the vent holes in flight and staining the top of the wing, and they can improve the fuel flow slightly. The biggest disadvantage to the system you described in your post is that if you fill both tanks and then park the plane on a slope so that one wing is lower than the other, fuel can flow from the high side to the low side and overflow the low tank and cause fuel to flow out the vent. Eliminating the vented caps and installing an interconnecting fuel vent system can stop this from happening even though it may not completely cure the problem of uneven feeding of fuel. Even the Cessna 150/152s I've flown don't always feed fuel evenly from each tank. -- Bryan Martin N61BM, CH 601 XL, Stratus Subaru. on 2/25/06 1:41 PM, Larry Bohannon at larryb54@alltel.net wrote: > --> Zenith-List message posted by: "Larry Bohannon" > > I was planning on installing the fuel system in my 701 as per plans. Now, with > all the talk of pumps,filters,ram air tubes in the stock vented gas caps, and > uneven flow from one tank or the other, I'm wondering what to do. > The plans have only the stock vented gas cap,a finger screen fitting at the > exit of the tank,the two hoses joining at the stock gascolator which is > mounted to the left of centerline at the low point of the fuselage and a > single hose running under the pilots seat to a single shutoff valve at the > pilots feet and then on to the engine. Has anyone flown with this per plans > setup for any length of time?? When I saw Roger's 701 I noticed there > appeared to be some clear filters in the lines where they entered the baggage > compartment and he had ram air tubes in the gas caps on top of the wings. I > don't know how the rest of Roger's system is set up but even Zenith's own > plane is not per their own plans!! What gives?? If we were to build it from > the plans would this be unsafe? The reason I bought the supposedly "complete" > kit and plans was that someone with the know how ( Chris H. and Zenith) had > already figured all this stuff out, but I saw in the Zenith newsletter about a > year or! > so ago, where Chris was giving info and a drawing of how to put the ram air > tube in the gas caps but there is nothing in the actual plans. How are we to > know what to do and what is safe if Zenith doesn't even follow their own > plans? Also, is anybody using the black rubber hose that came with the kit? I > seem to recall reading somwhere the rubber hose breaks down inside and the > pieces clog the carbs? > I'm almost finished with my 701 airframe and I will be installing the > engine and fuel system as soon as I receive the FWF kit I ordered from > Skyshop. i read where the biggest cause of accidents in homebuilts is the fuel > system. I only have a high school education but I can build according to > plans, if the plans are correct and safe, but can anybody tell me if the plans > are correct and safe or not? Should I follow the plans exactly, even if > Zenith doesn't, or should I modify? Any help/advice from the list would be > greatly appreciated. > Larry Bohannon > Winder, Georgia > ________________________________ Message 9 _____________________________________ Time: 03:14:25 PM PST US Subject: Zenith-List: Re: Questions About Bending Brake From: "Ron Lendon" --> Zenith-List message posted by: "Ron Lendon" I have had the same experience with narrow strips. I used the Malco hand shears to cut one of the doublers for the rear stabilizer spar. Both edges were cut by hand and it twisted. When I held it flat though the edges were straight. I bent it in a press brake and it became curved and twisted. Next time I will either shear or score break the trim edge. The other 3 doublers were shear cut and lay flat. The one I had cut was a remake and should have been shear cut. If you are good with a hammer and a dolly block you can stretch the edges back out and it will lay flat. It just takes a lot of patenience and care. I am going to use the strip as it will be held in place by the spar itself. More will be revealed as I get it closer to riveting. -------- Ron Lendon, Clinton Township, MI Corvair Zodiac XL, ScrapBuilder Read this topic online here: http://forums.matronics.com/viewtopic.php?p=14998#14998 ________________________________ Message 10 ____________________________________ Time: 03:29:41 PM PST US From: nyterminat@aol.com Subject: Re: Zenith-List: Aux fuel pump in 701. --> Zenith-List message posted by: nyterminat@aol.com Gary, This is my concern too. Has anyone ran a tank dry on purpose to see what happens? I like the idea of a header tank behind the seatback but I have installed a load of goodies back there. May consider something in the future though. Does the header tank get a separate vent or does it use the wing tanks as a vent? Bob Spudis N701ZX/912S Our only concern is: Can "air or vapor type lock" (sp?) happen if the right tank empties first complete and air goes inside the gascolator and the gasoline pump?... I will appreciate your advise, Frank... The electric fuel gauges could be so erratic... This is why I have the idea of installing a 1 or 2 gallons "header tank" behind the seat back (just in case has to be exactly in the middle of both seats!!! :-) and use the same gascolator. Saludos Gary Gower Flying from Chapala, Mexico 701 912S ________________________________ Message 11 ____________________________________ Time: 03:33:50 PM PST US From: nyterminat@aol.com Subject: Re: Zenith-List: Aux fuel pump in 701. --> Zenith-List message posted by: nyterminat@aol.com Tim I suppose that is possible. We were not offered any way of venting the tanks on the 701 other thann the fuel caps. Bob Spudis N701ZX do not archive -----Original Message----- From: Tim & Diane Shankland Sent: Fri, 24 Feb 2006 21:36:54 -0500 Subject: Re: Zenith-List: Aux fuel pump in 701. --> Zenith-List message posted by: Tim & Diane Shankland This situation might be caused by the differential pressure on the vents. The propeller is sending s spinning column of air back toward the wings, if the vent from the two tanks are not connected a different pressure can be present in each tank causing one to empty before the other. I plan on being able to feed form both tanks on my 601 so I connected the vents. Tim Shankland nyterminat@aol.com wrote: >--> Zenith-List message posted by: nyterminat@aol.com > > Gary, > >I have the exact same situation, except that my left tank empties first. My gasolator is right behind the pilots seat in the bottom of the fuselage. I have only been able to fly 15 hrs so far but the left one definately empties first. I tried switching fuel caps and it made no difference. I wonder if the tank being closest to the gasolator makes a difference? Where is yours? I also put individual tank shut off valves at each door header. I shut off my left one to balance out the fuel. I also have an aux pump in series with the fuel line right after the gasolator. Seems to work well, used to initally bring fuel to carbs on 1st start up. I also use it for takeoff and landing. > >Bob Spudis >N701ZX CH701/912S > >-----Original Message----- >From: Gary Gower >To: zenith-list@matronics.com >Sent: Thu, 23 Feb 2006 21:52:55 -0800 (PST) >Subject: Re: Zenith-List: Aux fuel pump in 701. > > >--> Zenith-List message posted by: Gary Gower > > > What we note in this first 35 hours of flying the 701, is that the right wing >uses the gasoline first, the left tank is about 3/4 full when the right wing is >near empty (1/4). in flights of more than 2 or 3 an hours (depending of the real >flight time, off course).> > > > > > > > > > ________________________________ Message 12 ____________________________________ Time: 05:11:07 PM PST US From: Carlos Sa Subject: RE : Re: RE : Zenith-List: Questions About Bending Brake --> Zenith-List message posted by: Carlos Sa I used the ZAC plans, but the plans at ch601.org are better. I think it cost about CDN$300 (it's been years), material and labour. Carlos --- William Dominguez a crit : > --> Zenith-List message posted by: William Dominguez > > Carlos, > > Did the welding shop built the brake from ZAC plans or > from the plans on http://ch601.org/. How much they > charged you. > > Thank you, > > William Dominguez > Plansbuilt 601XL Lche-vitrine ou lche-cran ? magasinage.yahoo.ca ________________________________ Message 13 ____________________________________ Time: 07:08:06 PM PST US From: "Brian Briggerman" Subject: Zenith-List: O-200 engine bolts hardware --> Zenith-List message posted by: "Brian Briggerman" I am putting an O-200 in my 601-XL and am having a problem finding the hardware to attach the engine to the engine mount. I have the rubber bushings, bolts, nuts and cotter pins shown on the lower center diagram on the drawing 6-CE-1. I can't identify the cup washers, spacer, hose and seat. I have been to my local FBO to try to get a setup for a Cessna 150. They could not identify the parts I need. I won't get the engine till later this week and don't know if there is a way to install it without those parts or not. If anyone know please let me know. Brian Briggerman Fountain Hills, AZ 601XL builder ________________________________ Message 14 ____________________________________ Time: 07:14:35 PM PST US From: Gdascomb@aol.com Subject: Re: Zenith-List: O-200 engine bolts hardware --> Zenith-List message posted by: Gdascomb@aol.com Check Aircraft Spruce catalog page 272. Part # and illustrations are there. ________________________________ Message 15 ____________________________________ Time: 07:24:55 PM PST US From: Gary Gower Subject: Re: Zenith-List: Aux fuel pump in 701. --> Zenith-List message posted by: Gary Gower The header tank (in the Kitfox and in my friends 701 instalation) has its own vent tube, but goes up to the same level of the wing tank vents, so no overflow will be there. Mean while we will fly the first hour in the left tank, once we get to level flight with both. Also be sure to have both on before beguining the landing. Saludos Gary Gower. nyterminat@aol.com wrote: --> Zenith-List message posted by: nyterminat@aol.com Gary, This is my concern too. Has anyone ran a tank dry on purpose to see what happens? I like the idea of a header tank behind the seatback but I have installed a load of goodies back there. May consider something in the future though. Does the header tank get a separate vent or does it use the wing tanks as a vent? Bob Spudis N701ZX/912S Our only concern is: Can "air or vapor type lock" (sp?) happen if the right tank empties first complete and air goes inside the gascolator and the gasoline pump?... I will appreciate your advise, Frank... The electric fuel gauges could be so erratic... This is why I have the idea of installing a 1 or 2 gallons "header tank" behind the seat back (just in case has to be exactly in the middle of both seats!!! :-) and use the same gascolator. Saludos Gary Gower Flying from Chapala, Mexico 701 912S --------------------------------- Bring photos to life! New PhotoMail makes sharing a breeze. ________________________________ Message 16 ____________________________________ Time: 08:16:31 PM PST US From: ruruny@aol.com Subject: Zenith-List: RE: Aux fuel pump in 701.Aux fuel pump in 701. --> Zenith-List message posted by: ruruny@aol.com I am using the 701 stock fuel system also, except I have 10 gal aux tanks in each wing outboard of the standard tanks. I'm running the rubber fuel hose per plans. Actually the plans are very vague on much of the installation of this stock system. One of the problems I'm facing is locating the (2)stock gascolaters in the proper place behind the pilots seat. It seems the plans setup will not work as the fittings/hose will intefere with the flap handle. Each of these have a drain which limits you on installation options. The aux tanks both meet at one of these gascolaters,and the main tanks meet at the the other. Rubber fuel line exits the gascolaters and go up to a selector on the floor,just in front of the seat under my left leg. It will be labeled inboard, outboard, off. 1 hose exits the selector(same size hose) and travels along the left side fuselage to the right side of the firewall where I have installed an ACS gascolater. If I'm on the main tanks and they drain unevenly in flight, I guess I could select the aux tanks for awhile so the mains could balance out. One question that I have is which tanks should I use first , the inboard or outboard thanks? Would it be wiser to drain the outboard tanks down first? Also, what about eliminating the 2 gascolaters behind the seat and use a TEE to connect them together, then continue on to the selector. This would help in fitting everything in behind the seat without inteference and still leave drains in each wing and the ACS gascolater? My only other option is using aluminum fuel line and AN fittings, which I have no experience or idea or tools or how to do or get started.This would be a great Homebuilthelp video topic.I'm at a point with this project where there are more questions than answers with fuel and electrical. I'm tackling the electrical slowly in the cold garage this winter, but the fuel system is causing overload,so I've been avoiding the topic and work on it. If anyone has pics of their install behind the 701 seat it would be much appreciated. And thanks for all the help, I like when the discussion of 701 fuel system options gets going. I feel I know quite alot about the 601 system from the many discussions of it on the list, thanks for looking at the 701 also and helping out. Brian Long Island N701BU 912