Next step is starting to install the landing lights on my right wing. Again this is the Landing light kit by DuckWorks aviation. Just like the last time, I lay out the template on the leading edge, aligning it on the rivet lines, etc. I then drill the four corners using my uni-bit to make some starting holes.
Next I transition to my harbor freight saw to make the rough cuts. I’m still having a little difficulty controlling this saw so I keep things fairly rough and then follow up with the pnumatic nibbler. Next it’s on to the files to get everything even and smooth.
I then fabricate the light bracket and get the angle aluminum trimmed to size and drilled, followed by getting the nutplates installed on the leading edge. Next it’s time to drill the lens attachment points and to get the attachment hardware all set up and preped for priming.
I also mask off the acrylic lens with painters tape and get it marked so I can begin trimming it. (More on that in one of the next videos). I did verify that my metal bandsaw blade cuts the acrylic well!
Ok, so while I’m getting better at the whole Proseal thing, I’m not a fan. Also due to some of my dislike of the whole process I really was not in the frame of mind to start the camera. I’ll attempt to better capture my struggle with the next tank, but no promises!
At this point I have basically finished up everything on the first tank with the exception of the rear baffle. I also have a handful of rivets I need to remove and reset as they didn’t go in flat or the shop head didn’t form correctly. Once that is done, I’m going to put the tank into storage for a month or so to allow the proseal to fully cure.
Some notes on this section. The fuel drain does not fully seat into the flange. At first I thought this was due to some proseal in the threads or something else, but no this is normal and don’t force it to thread in too far. (Snug then just a little more!) Installing the fuel vent line was a little bit of a pain and required some fiddling to assist in getting the fuel float installed. The plans give you an example, but does not really reflect reality! Same goes for the fuel float.
For the fuel float, spend time to understand how everything gets assembled before you cut anything. I originally thought I was completely hosed, but I think I did ok. VANS no longer sells replacement wire / floats as the MFG no longer offers replacements (changed in early 2018). The end of the wire is a “L” and goes through the sender and clips into the arm. That should make sense when you look at the sender.
I initially made the 4-1/8 x 4″ bends per the plans, but then had to make some really funky bends to get the wire and float to clear the vent tube / ribs. I tried to get my float and sender to fully bottom out on the bottom of the tank just before full deflection on the sender. I think I’m basically full deflection with the float against the skin, and I’m against the top of the tank before full deflection in the full position. Double checked with a multi-meter to show 240 Ohm empty and 50 Ohms full.
Last items I need to do before I put the tank into storage is proseal the vent fitting and fuel sender and install the fuel supply fitting and fuel return fitting (no proseal). I’ll then cleco the rear baffle in place and put it away.
After the holidays I’ll probably jump back to the Leading edges to fix a few rivets, finish up the Leading Edge lights and plexiglass. Then maybe the top skin on the Left wing depending on weather and my ability to spray primer.
Ok, so I’ve been anxious about starting the next step for the fuel tank but finally decided the time is now. It’s time to start to apply proseal and rivet the tank!
Well, let’s back up just a little bit and talk about the prep. Standard stuff, deburr all the parts, and get them appropriately dimpled. I went with the Cleaveland Tank skin dies for the skins, and the sub-structure dimple dies for all the stiffeners and such. I also did all the necessary countersinks and hopefully made the right call to countersink the tank attach bracket that wasn’t specifically called out. Guess the expectation is that the builder needs to start figuring our more stuff on their own.
The other thing I was researching and deciding upon was how I was going to apply the proseal and what system to rivet the parts. Specifically I decided to buy a few of the 3.5 oz tubes of proseal and to use the pneumatic dispenser to hopefully keep the mess to a minmum. I also decided to follow the suggestion here on how to complete the assembly. Basically I will apply a layer of proseal and then cleco the parts together. I then shape and clean up the edges of the part and allow the proseal to set-up. I then come back and remove the clecos one by one and wet-rivet the parts together to complete the process.
The down-side to this process with the pre-measured tubes is that this can be wasteful. I was able to do all the attachments to the ribs, the stiffeners, and the fuel tank cap with 1 tube. Then I riveted all the parts on the ribs and riveted all the parts on the top of the skins and ended up wasting about half a tube. (Mostly as I ran out of time and had to call it a night). I have the Qt container of proseal on order and plan on mixing up some smaller batches when I need to rivet.
Also not sure how visible it is in the time lapse, but I didn’t do this with the fuel gauge nutplates. Ugh, I can start to see why this recommended method is so much nicer.
Next project is to start the fuel tanks. I started by pulling all the parts and making the tank stiffeners. Only issue is that the tank stiffeners are longer than the throat on my band-saw, so I ended up using my snips to rough cut them to size. Then used the bandsaw to cut the angle on the ends, followed by finish sanding on the belt-sander and deburring on the bench grinder. Then I trimmed, sanded and deburred the Z tank attach brackets. I ended up trimming these parts for both tanks at the same time.
Then it was on to straightening the ribs for both tanks as well as getting them deburred. Then it was on to measuring, cutting and deburring the J-channel for both tanks.
So I’m making progress on building the fuel tank (forgot how enjoyable it was to make progress!) and just about at the point where I’m ready to fully disassemble / deburr / dimple. Per my previous post, I was able to adjust the skins for the locking fuel caps and now I’m at the point where I’m trying to figure out how to fabricate a fuel return line.
So I’m not an engineer or true engine monkey, however in the research I have been doing, if I decide to go with one of the EFII solutions (either FlyEFII or SDS), then I’ll also need to have a way to return fuel to the aircraft tank. Basically their designs will return any excess fuel back to the tank. This requires not only a fuel return port / line, but also a duplex fuel selector valve so when you pull fuel from the right tank, it returns excess fuel to the right tank. Plenty of discussion on VAF for those that want to know more and I’ll possibly get into it more later in the build. For now however I would rather add the port before the tank is sealed vs trying to do it as an afterthought later.
Currently my thought is to add a second VA-141 fuel flange to the inboard aft rib. It’s not obvious but based on experiences from other via VAF, you don’t want to do this in the area shaded in RED. My plan is to add it to one of the areas in greed below.[inpost_fancy thumb_width=”200″ thumb_height=”200″ post_id=”695″ thumb_margin_left=”0″ thumb_margin_bottom=”0″ thumb_border_radius=”2″ thumb_shadow=”0 1px 4px rgba(0, 0, 0, 0.2)” id=”” random=”0″ group=”0″ border=”” show_in_popup=”0″ album_cover=”” album_cover_width=”200″ album_cover_height=”200″ popup_width=”800″ popup_max_height=”600″ popup_title=”Gallery” type=”fancy” sc_id=”sc1539183671197″]
I have some AN fittings as well as the VA-141 flanges on order to do some test fittings to make sure this will work as well as a message on the VAF to make sure I’m not missing anything. Hopefully everything arrives by Friday so I can possibly start the “dreaded” proseal process this weekend? Currently have 2 tubes of proseal on order that also hopefully arrives. I think i’m going to stick with the pre-measured stuff that you mix in the tube based on some posts about proseal de-curing currently being discussed?!?!
Update: Looks like using a second VA-141 fuel flange from VANS, as well as a AN816-6-6D Nipple should do the trick. Honestly this appears to be similar to the Bung that EFII is selling, just internally mounted vs externally mounted?