Original Posted By: "Egan, John"
Subject: Re: Pietenpol-List: a serious post about cutting 4130 sheetIn a message dated 4/28/2006 11:28:19 A.M. Central Standard Time, Michael.D.Cuy(at)grc.nasa.gov writes:from having to band saw them up, not to mention saving the price on what Aircraft Spruce or others charge for 4130 strip material.Wicks would always strip a sheet of 4130 18 in X 18 in to my specs without any extra charge.________________________________________________________________________________Subject: Pietenpol-List: Gas Tank LocationDate: Fri, 28 Apr 2006 11:57:58 -0500
Pietenpol-List: Gas Tank Location
Re: Pietenpol-List: Gas Tank Location
Original Posted By: Tim Willis
Subject: Re: Pietenpol-List: Gas Tank LocationIn a message dated 4/28/2006 11:59:50 AM Central Standard Time, jegan(at)kcc.co=mwrites:Would any one like to comment on how low the bottom of the fuel tank shouldbe mounted (or their successful installation) in the nose area of a Piet? I=would like to start to mock up the fuel tank to be located in the nose,supplying fuel to an updraft carb, mounted under a Corvair engine. I will c=omplete aflow test as discussed in previous valued comments found in the archive.Thanks all,John Fuel related problems are the most common reason that airplane enginesstop running. There are a LOT of factors to consider when designing a fuelsystem. Some of which are:1) The outlet should be the lowest point in the tank, in order that ALLwater will find it's way out when the plane is in the static laden position(sitting tail on the ground).2) There should be a removable finger screen in the outlet, to catch all th=egarbage that seems to find it's way into the tank.3) The mounting system must be able to sustain at least 3 times the weightof the total fuel capacity.4) Quantity indicator must be reliable, and be able to monitor it in flight=- Not Electric..too unreliable. A fuel cap with a cork & wire indicator issimple and easy to make, and should also include a 90=BA Ram tube (1/4" tubi=ng)facing into the prop wash - to maintain a little bit of pressure in the fuel=tank.5) Fuel shut off valve on Certified planes must be behind the firewall, but=I put mine on the front of the firewall before I realized that fact. Myreasoning is that there is No portion of my fuel system inside the cockpit a=rea -no leaks can find their way into the cockpit.6) 3/8" fuel lines to maintain enough quantity flow.7) Gascolator Must be in the lowest point in the fuel system (even lowerthan the carb), to collect water. However, it Must be above the lower edge=20=ofthe firewall, in case you wipe out the landing gear, it will Not rupture the=fuel lines. For my cowling tank, the bottom is sloped forward, so when the plane isin the static laden position (tail on the ground) any drops of water will dr=ainout of the tank, into the gascolator. No fuel lines or fittings are in thefront cockpit. I installed a fitting on the top, at about 10 O'Clock positi=on(viewed from the cockpit), to fill it from the wing. My quantity indicator=20=isa cork & wire, similar to a J3. I made my fiberglass cowl tank with the flanges on the sides of the tank=,to rest on the top of the longerons. I put a lot of time and thought intothe mold for the tank. I made the inlet on the top left side, (at about 10O'clock pilot's view), and made a fiberglass blister stand outboard of thecowling, to prevent possibility of leaks entering the cowling. The outlet i=s alsooutside of the cowling shelf, and points forward. There is an EL fitting, t=henthe 3/8" ball valve that is cable operated. The bottom of the tank slopesforward, while in the tail down attitude (as it sits in the hanger), so any=20=waterin the tank makes it's way all the way out of the tank, and into thegascolator (a very important design criteria). I used the aluminum 'weldabl=efittings' that AS&S sells, glassed in, at the inlet and outlet. On the outl=et side, Imodified a finger screen, so it threads into the 'weldable fitting', bytaping the o.d. threads, and then the 90=BA EL threads into the 'weldable f=itting'on top of the finger screen. As a result, I was able to squeeze a lot of fu=elin the cowling tank. It holds 10.7 gals. I didn't know how much fuel itwould hold, till I did a leak test, by setting it up at the gas pump, at the= anglethe tank sits in the plane, and put one gallon in at a time, then dipping astick into the fuel, to mark off each additional gallon. That's how I made=20=my'Fuel Quantity Indicator'. I topped it all the way off, then put the fulltank in my trunk, brought it home and left it sit for 3 or 4 days to check f=orleaks - No Leaks !! My wing tank holds 9.8 gals. so my total fuel onboard=20=canbe 20 gal. That's a lot of fuel. I don't think I could sit there longenough to burn that much fuel at a time, but on the way back from Oshkosh, I= did doone 4 hr leg, and two 3 1/2 hr legs, and still had plenty of reserve. Butyou know what they say - "The only time you have too much fuel onboard, is w=henyou're on fire !!" It was quite a chore to design and build this tank, but=20=itall works very well, and I'm pleased with how it turned out. I have lots of=pictures at : http://nx770cg.com/FuelSystem.htmlChuck G.NX770CG________________________________________________________________________________Date: Sun, 30 Apr 2006 07:40:28 -0700 (PDT)
Subject: Re: Pietenpol-List: Gas Tank LocationIn a message dated 4/28/2006 11:59:50 AM Central Standard Time, jegan(at)kcc.co=mwrites:Would any one like to comment on how low the bottom of the fuel tank shouldbe mounted (or their successful installation) in the nose area of a Piet? I=would like to start to mock up the fuel tank to be located in the nose,supplying fuel to an updraft carb, mounted under a Corvair engine. I will c=omplete aflow test as discussed in previous valued comments found in the archive.Thanks all,John Fuel related problems are the most common reason that airplane enginesstop running. There are a LOT of factors to consider when designing a fuelsystem. Some of which are:1) The outlet should be the lowest point in the tank, in order that ALLwater will find it's way out when the plane is in the static laden position(sitting tail on the ground).2) There should be a removable finger screen in the outlet, to catch all th=egarbage that seems to find it's way into the tank.3) The mounting system must be able to sustain at least 3 times the weightof the total fuel capacity.4) Quantity indicator must be reliable, and be able to monitor it in flight=- Not Electric..too unreliable. A fuel cap with a cork & wire indicator issimple and easy to make, and should also include a 90=BA Ram tube (1/4" tubi=ng)facing into the prop wash - to maintain a little bit of pressure in the fuel=tank.5) Fuel shut off valve on Certified planes must be behind the firewall, but=I put mine on the front of the firewall before I realized that fact. Myreasoning is that there is No portion of my fuel system inside the cockpit a=rea -no leaks can find their way into the cockpit.6) 3/8" fuel lines to maintain enough quantity flow.7) Gascolator Must be in the lowest point in the fuel system (even lowerthan the carb), to collect water. However, it Must be above the lower edge=20=ofthe firewall, in case you wipe out the landing gear, it will Not rupture the=fuel lines. For my cowling tank, the bottom is sloped forward, so when the plane isin the static laden position (tail on the ground) any drops of water will dr=ainout of the tank, into the gascolator. No fuel lines or fittings are in thefront cockpit. I installed a fitting on the top, at about 10 O'Clock positi=on(viewed from the cockpit), to fill it from the wing. My quantity indicator=20=isa cork & wire, similar to a J3. I made my fiberglass cowl tank with the flanges on the sides of the tank=,to rest on the top of the longerons. I put a lot of time and thought intothe mold for the tank. I made the inlet on the top left side, (at about 10O'clock pilot's view), and made a fiberglass blister stand outboard of thecowling, to prevent possibility of leaks entering the cowling. The outlet i=s alsooutside of the cowling shelf, and points forward. There is an EL fitting, t=henthe 3/8" ball valve that is cable operated. The bottom of the tank slopesforward, while in the tail down attitude (as it sits in the hanger), so any=20=waterin the tank makes it's way all the way out of the tank, and into thegascolator (a very important design criteria). I used the aluminum 'weldabl=efittings' that AS&S sells, glassed in, at the inlet and outlet. On the outl=et side, Imodified a finger screen, so it threads into the 'weldable fitting', bytaping the o.d. threads, and then the 90=BA EL threads into the 'weldable f=itting'on top of the finger screen. As a result, I was able to squeeze a lot of fu=elin the cowling tank. It holds 10.7 gals. I didn't know how much fuel itwould hold, till I did a leak test, by setting it up at the gas pump, at the= anglethe tank sits in the plane, and put one gallon in at a time, then dipping astick into the fuel, to mark off each additional gallon. That's how I made=20=my'Fuel Quantity Indicator'. I topped it all the way off, then put the fulltank in my trunk, brought it home and left it sit for 3 or 4 days to check f=orleaks - No Leaks !! My wing tank holds 9.8 gals. so my total fuel onboard=20=canbe 20 gal. That's a lot of fuel. I don't think I could sit there longenough to burn that much fuel at a time, but on the way back from Oshkosh, I= did doone 4 hr leg, and two 3 1/2 hr legs, and still had plenty of reserve. Butyou know what they say - "The only time you have too much fuel onboard, is w=henyou're on fire !!" It was quite a chore to design and build this tank, but=20=itall works very well, and I'm pleased with how it turned out. I have lots of=pictures at : http://nx770cg.com/FuelSystem.htmlChuck G.NX770CG________________________________________________________________________________Date: Sun, 30 Apr 2006 07:40:28 -0700 (PDT)