Sight gauge innerds

[neverquit]

Vance has some nice gauges but they seem a bit pricey. The plastic and lights would be easy to get. Looks like all you'd need to do is heat up some clear plexiglas or lexan over a wooden dowel. About ten bucks worth of materials maybe? I thought of taking a piece of clear plastic or glass tube with a 90 deg. bend in the top and the bottom similar to the Velocity setup. Two holes in the side of the use and flox the tube in. Backlight it and you're set.

Chris, you tried a bait shop? They have those fake spawn balls or little balls like that for spinners and such.

[chasingmars]

Originally Posted by MarbleTurtle

Anyone else planning to skip the sight guages? From what I've read, they are difficult (impossible?) to see clearly in flight, and if you only use them on the ground, just check tank level at preflight.

I'm starting to get towards that stage of the plans... If I'm planning on having good capacitance based senders, I was wondering the same thing, do I still need sight gauges. I guess the answer to that is the question: "How easy is it to dipstick the tanks on preflight"? Both methods physically verify fuel, and dipsticking is what I'm used to at the moment (although, in weather like we've been having, it would be nice to be able to check fuel out of the cold!)... I guess I'm trying to balance this against the (admittedly minor, I hope) issue of the sight gauge introducing a weak area in the separating structure between the fuel tanks and the cockpit.

Any comments on the above would be appreciated. Realistically, I'll probably put in the window, but as a backup system, not the sight gauges.

[John Slade]

You're used to only being able to see your fuel once - during pre-flight. There's nothing quite flying for 3.5 hours in a stiff and variable wind at different altitudes, passing overhead a fuel stop, knowing you're about 45 miles out from your destination and looking back to see exactly how much fuel is remaining in each tank. I have capacitance gages installed. Just like in navigation, I like to have at least two indicators for the same thing. If they agree I'm comfortable. If they disagree, then I need to find out which one is right. The sight gages are [almost] always right.

Given that these gages have worked without problems for hundreds, if not thousands of flyers and given that failure could mean 60 gallons of fuel in the cockpit, my suggestion would be to spend the $70 or whatever Vance gets these days and install them.

[chasingmars]

Originally Posted by John Slade

You're used to only being able to see your fuel once - during pre-flight. There's nothing quite flying for 3.5 hours in a stiff and variable wind at different altitudes, passing overhead a fuel stop, knowing you're about 45 miles out from your destination and looking back to see exactly how much fuel is remaining in each tank. I have capacitance gages installed. Just like in navigation, I like to have at least two indicators for the same thing. If they agree I'm comfortable. If they disagree, then I need to find out which one is right. The sight gages are [almost] always right.

Given that these gages have worked without problems for hundreds, if not thousands of flyers and given that failure could mean 60 gallons of fuel in the cockpit, my suggestion would be to spend the $70 or whatever Vance gets these days and install them.

That's a compelling argument. When viewed as cost/benefit, makes sense to just have both. The diagrams on his site have mostly cleared up my concern about having a weak area between the fuel tanks and cockpit.

[MarbleTurtle]

Anyone know how the sight guages hold up to alcohol in autofuel (ethanol mixes)?

[chasingmars]

Originally Posted by MarbleTurtle

Anyone know how the sight guages hold up to alcohol in autofuel (ethanol mixes)?

Hmmm, good question, and if I can avoid the inevitable questioning looks, to methyl esters of vegitable oils (i.e. Biodiesel), Road diesel, Turbine fuel and such other things a compression ignition engine might run on?

[chasingmars]

Originally Posted by Ben

Thinking aloud...

How about using balls from a car battery tester (hydrometer). They stand up to being used in sulfuric acid... The specific gravity of fuel is less than battery acid, I assume they'll float? They come colored, don't know if this is a coating or part of the plastic...

Um, maybe I'm just overtired, but it seems to me that if you take a ball of something that's close to neutrally buoyent (i.e. just floats) in fluid A (battery acid, say) and put it in some fluid B that's *less* dense (say fuel)... won't it sink?

Oh, and the type of attack that an acid gives (oxidization?) is pretty different to what a fuel might (solvent), so I'd not drwas conclusions without extended testing or data.

[Dust]

my sump thingy for planes has a ball in it - floats in fuel, not in water