Didn't know about the fuel volume variance. I stand corrected. Good thing you're doing a new weigh-in Rob.

When I did my 170 I was going to fill it and subtract until delair Harry pointed out the inboard caps thing.
So then I drained it from the low point drain at the fire wall then the wing ones. there is an amazing amount of fuel still in the tanks, in the three point attitude on bushwheels, after it quits coming out of the firewall drain.
Mine ended up at 1360 on bushwheels with no back seat.

A side benefit of completely draining the tanks, is that you could use the opportunity for visual inspection and removing any contaminants.

Rob: I know you're getting lots of suggestion on this but I'll throw in my 2 cents anyway:

If you have the time with scales and fuel readily available, I would weigh it empty w/unusable, then I would fill it incrementally to check your fuel gauges and calibrate a dipstick or whatever you normaly use for checking fuel level and also record the weights at 1/2 tanks and full to give yourself real numbers for flight planning purposes.

Good luck! The project looks great!

I agree. My plan: Weigh empty in flight attitude. Then stick the tanks every 2 gal per wing till full w/ the TW down. Then weigh again once filled. This way I will have an exact way to quantify fuel lvls on the ground outside of gauges as well as real weights.

All this aside, you are doing a great job Rob. Not many guys realize just how much work this stuff takes and how committed one has to be do get thru it all. You are certainly right there in the deep end of the pool. (In fact I think I see you over there thru the murky water.) I Wish I could tell you it gets easier, but it will get much tougher before you are on the upswing. Keep the faith brother. It will be all worth it in the end. Beers on me when we meet.

BUT, Gary, bear in mind that "Useable Fuel" implies that fuel which the airplane can use in "normal flight". In fact, the new rules require quite a bit more fuel than the old rules, due to requirements to feed fuel in a variety of "flight attitudes". Just because you can drain it out while the plane is sitting in a hangar doesn't necessarily imply that the engine can access that fuel in flight, as in a descent for example

I just wanted to get an idea what I had a certain point on the low end of the tank. I figured the best way was to check in level flight. So, I drained all the fuel when level. Shut the tank valve off, put five gallons in each tank and marked the glass. That gives me a good hour to get more gas, and that works for me.

I have fuel scan, but I like to double check it against the gauges at a known point.

Gary

I started stripping the top of the wings today and I got about 3/4 of the way done.

Hey Rob,

Are you going to stick with the original gear legs or upgrade to 180 or Lady Legs?

Curious your thoughts after running the old style gear in the ruff stuff.

I started with stock legs on my 52' 170B and upgraded to early 180 legs. Was a great upgrade and I'd do it again.

Upgrading the gear won't be part of this project. If I can find a set of 180 gear at a reasonable price I may upgrade in the future. Although I'm not sure it's necessary? There are a lot of opinions on this, the soft gear probably transfers less abuse to the airframe than the stiffer 180 gear. The added prop clearance and increased angle of attack in a 3 point attitue with 180 gear would be nice though. I also wouldn't want to put any larger tire than the 26'' bushwheels on with the soft gear. They do move around a little bit in flight and I think having a larger heavier tire hanging out there would make it worse. One thing I don't like about the soft gear is that double puck brakes won't mount forward or aft with the standard tourqe plates. I had to get 6 hole torque plates and rotate the caliper down to clear the bottom of the gear leg. This puts the caliper closer to the bottom of the tire where it flexes most and you get some slight rubbing on the sidewall of the tire. I put spacers inbetween the brake disc and rim to get the caliper further out and reduce the risk of rubbing. It hasn't been a serious issue so far and Wup at AKBW has looked at my setup and thinks it shouldn't be an issue. I've noticed some spring gear Maules have to do this also so I'm not the only one. Lady legs or 180 gear have a narrower ankle and the double puck clevelands can be mounted straight forward or aft, no need for spacers and less of a chance of rubbing the caliper.

I replaced the old rusty screws holding the fuel tank covers on with new stainless steel ones. What sounded like a simple job turned out to be a real pain in the ass! (I'm actually not all the way done)


I got both of the flaps stripped this weekend, not much stripping left to do now.

Looks great Rob! Looking forward to seeing pieces go back on!

Flynengr

robw56 wrote:I replaced the old rusty screws holding the fuel tank covers on with new stainless steel ones.

You might want to reconsider that Rob. They're rusty because the zinc/cadmium was sacrificed in the electrolytic corrosion, protecting the steel and aluminum. The potential between the aluminum and stainless steel is considerable and the aluminum loses out. Better off to replace the screws as they first start to rust, they're cheap and you get nice fresh heads while protecting the wings.

Mark J

the fuel tank covers are structural - not sure stainless is what you want.. When I pulled my tanks my IA insisted on on the standard cad plated steel AN hardware. FWIW.

looking good Rob - that is a mighty effort.

^^^^^^^^^ What Mark J said ^^^^^^^^^^^^

Those stainless screws (corrosion resistant) appear to be a MS27039C, which is a structural screw. They are small in the picture, could be wrong.

It's fine to use SS screws on aluminum airplanes, they've been all over every seaplane I've ever worked on. It is important to use an aluminum washer (AN960JD) as a sacrificial shim. Simply replace them when they get fuzzy.

Some grease on the thread helps too.

The kit I bought is all structural stainless screws. Is it really not a good idea? They make the kits for several planes. If they caused problems I'm sure they wouldnt be selling them but I could be wrong. I also have non-structural stainless steel screws all over the rest of the airplane wherever I can use them. I've never heard anything bad about stainless but I'm not as experienced as a lot of you guys.

The problem with stainless screws, as noted by others is that the aluminum in the structure and skins is lower on the galvanic scale (or whatever it's called) than stainless. So, the "sacrificial" metal in the corrosive process is the aluminum structure, which is more expensive and harder to replace than the screws.

That said, lots of folks and some manufacturers use stainless screws in sheet metal.

I would use plastic (not aluminum) washers under the heads of the screws, and dip the screws in some anti corrosion primer just prior to installing them.

I'd go ahead with the stainless screws, but take some precautions.

MTV

I wouldnt sweat it Rob. Use the structural SS and dont worry about it.

FYI, they suck to get out once they start to rust. Then the heads strip. Then the fun starts. The plastic washer does seem to help