danielhv

danielhv

Well Known Member
Several questions here. Im working on wings.

Need conduit. 25' roll or 50'? And is the Nylon stuff from Vans the best to get?

Flops tubes... ordering one from Vans (unless there is somewhere better...) Sould I get 1 or 2? Says u only need it in 1 tank... anybody have problems with just 1?

Proseal... How much for fuel tanks? Im going to get my hands on a Semco gun, so no popsicle sticks if I can keep from it!

Im swapping my standard fuel caps out for the Deluxe locking caps.

Anything else I need?
 
ordering stuff

I'm about at the same place. I just started riveting wings. Did stiffeners today. Here is list of stuff to consider: I'm doing 2 flop tubes just so it is the same on both sides for both building and flying. Did you do fuel return lines? If so, then you'll need to order 2 each of the same fittings used for the vent tube. You have enough tubing in the coil they give you in the kit. I did the delux caps and like them. I bought one can of Proseal. 1 quart of MEK. Popcycle sticks and I like them. Pop sticks are good for mixing. Napkins (not rags). Scale to measure Proseal (get at Office Supply Store). Plastic cups from grocery store to mix Proseal in. Blue tape and electric tape to mark off spots you don't want proseal on. I wrap my rivet gun handle with tape to make clean up easier later on. Have Fun.
 
sglynn said:
I'm about at the same place. I just started riveting wings. Did stiffeners today. Here is list of stuff to consider: I'm doing 2 flop tubes just so it is the same on both sides for both building and flying. Did you do fuel return lines? If so, then you'll need to order 2 each of the same fittings used for the vent tube. You have enough tubing in the coil they give you in the kit. I did the delux caps and like them. I bought one can of Proseal. 1 quart of MEK. Popcycle sticks and I like them. Pop sticks are good for mixing. Napkins (not rags). Scale to measure Proseal (get at Office Supply Store). Plastic cups from grocery store to mix Proseal in. Blue tape and electric tape to mark off spots you don't want proseal on. I wrap my rivet gun handle with tape to make clean up easier later on. Have Fun.
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Is there a diagram somewhere to show the fuel lines etc and how they are run? Cause I am confused on the return line, vent tube, etc. :confused:

I dunno what I need as far as that goes... I'm planning on fuel injected.
 
Fuel vent and return line

Yes, the vent line is shown on drawing 16A. All the fitting part numbers are listed. Return line is not shown on the drawing nor discussed in the plan. Make your return line the same as the vent line, except dump it into the middle bay. Some say to dump it low in the tank to avoid static electricity from the hot foaming fuel that returns. Others say dump it high. If you are going to use a carberator engine, you probably don't need a return line.
 
sglynn said:
Yes, the vent line is shown on drawing 16A. All the fitting part numbers are listed. Return line is not shown on the drawing nor discussed in the plan. Make your return line the same as the vent line, except dump it into the middle bay. Some say to dump it low in the tank to avoid static electricity from the hot foaming fuel that returns. Others say dump it high. If you are going to use a carberator engine, you probably don't need a return line.
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I see... Im trying to find a couple of websites that explain the pro's & con's of running the return fuel line etc... Diagrams that show how the lines are routed, anything... because I am confused about the entire theory. :(
 
Dan,

If you're looking for conduit for wiring, I think the best thing is 5/8" irrigation drip tubing. Enlarge and/or add holes for this in your ribs and it fits snugly through the holes without any fasteners. Depending on how many wires you are running, probably 50 feet would be plenty, but the stuff is cheap and light.

greg
 
Daniel,

I just finished my first tank. Check out my site. I ordered 50' of conduit. 25' would just barely be enough. I wanted to have plenty, and for the price break, I went with the 50' roll.

I am doing flop tubes in both tanks. I bought one from Van's and one from here. If you buy one here, the nuts may not be drilled for the service bulletin and you will have to do this yourself. It can be tricky to drill the nut on an angle, but I managed to get it done.

I used just over 1 qt of MEK on one tank. I also used an entire quart kit of Proseal on one tank, though a lot of that ended up in the garbage. I did use a lot of proseal in my tank though, because I did not want a leak. I wasn't very careful about where I got it inside the tank - it won't matter. I did use a little bit of black electric tape to cover up the screw holes on the edges of the tank. While it weighs more, I figure that more is better in the case of Proseal. My tank was leak free on the first try.

I already had a kitchen scale. I put it in a large freezer bag to protect it. I used the wide popsicle sticks with the rounded tip cut off so that it was flat. The tin snips cut popsicle sticks very well. I also used the ziplock bag method on the baffle, it worked great. You will need buckets to put dirty clecos in. Make sure these buckets can handle MEK without melting. I mixed my proseal on cardboard. Flat surfaces are better for mixing, because one part of the mix can't get trapped in the corners of the bottom of a bowl or cup. I also spread a LOT of proseal and did all my fillets with my finger tip - no glove. Gloves just got in the way and I quit using them early on. I tried not to touch MEK too often with bare hands. Gabe's Grit took proseal off rather well at the end of a work day.

I used AN6 return lines, so I purchased some 3/8" ID snap bushings, 10 feet of 3/8" aluminum tubing, AN818, AN819, AN929, AN833, AN924 (one of each per tank) for the return line. You'll also want an AN929 for the vent line during leak testing. Speaking of leak testing, check out my site for how I did mine. I used a short piece of 3/8" OD tube flared with an AN818 and AN819 on the flop tube fitting, 3/8" ID clear vinyl tubing, and a hose clamp. Get some EZ-turn to seal the fuel cap and fuel drain also.

Sounds like you're only a few steps behind me. Good luck.

Oh, and I can't take credit for everything on my site - I use Brad Oliver, Mike Nipp, and Dan Checkoway's sites quite often for tips.
 
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Geez.... ok, I am not very familiar with the tubing and such, but I am assuming that -6 is larger (ID?) than -4... I am also assuming that when ordering fittings, they should have the same -#. So, here is my list.... Can you guys PLEASE take a careful look at this and make sure I have everything I need? I know im asking alot, but I am pretty confused at this point. I believe I have the tubing for the return lines, some fittings for the return lines (although I do not know what or where they go yet!), some bushings for the return lines (hope thats enough)! Man, this is an expensive parts order. :(

vansorder.jpg
 
**50' roll of nylon corrugated tube - GOOD
**Flop tubes - GOOD
**Quart kit of Proseal - GOOD. This will get you at least through the first tank. Building both together or separate?
**Fuel caps - GOOD
**3/8" ID snap bushings - GOOD. I used 2 per tank, but it doesn't hurt to have extra.
**3/8" OD aluminum tube - GOOD. Some people use 1/4" OD for fuel returns, but I went 3/8" just for extra comfort. Eight feet should be plenty for both tanks.
**AN818-6D x 2 - these are for your fuel returns, both tanks.
**AN819-6D x 2 - these are for your fuel returns, both tanks.
**AN929-6D x 3 - I should have been clearer with these. These are blanking off caps. I am using them to blank off the fuel return lines, because I plan to go carbuerated initially. If you plan to go FI from the start, you won't need these. You will still want at least one of them though to cap off the fuel return line during leak testing.
**AN833-6D x 2 - these are for your fuel returns, both tanks.
**AN924-6D x 2 - these are for your fuel returns, both tanks.

Not shown that you will need is an AN929-4D. This is a cap to blank off the vent line during the leak test. It is -4D because it is for the smaller fitting on the fuel vent.

Do you have the Standard Aircraft Handbook? It has a chart that shows all the AN fittings that is so-so. I have made a spreadsheet I can email you that will explain AN fittings better with pictures if you'd like me to email it to you. Just PM me your address. the suffix on AN fittings stands for the size and material. For instance, -4D will fit a 1/4" OD tubing (the 4 stands for the X in X/16 = 4/16 = 1/4), and the D means that the fitting is aluminum and not steel.
 
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Greg Arehart said:
Dan,

If you're looking for conduit for wiring, I think the best thing is 5/8" irrigation drip tubing. Enlarge and/or add holes for this in your ribs and it fits snugly through the holes without any fasteners. Depending on how many wires you are running, probably 50 feet would be plenty, but the stuff is cheap and light.

greg
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I would strongly suggest you use snap bushings in the rib, feed the tubing through the snap bushings.

Vibration will cause the rib to slice through the bare tubing after time.

You might also consider running two tubes out from the root----stop one at the aileron bellcrank cover, the other runs out to the tip. Each wing.
 
RV7Factory said:
FYI... I put return lines in, but now I am thinking they will go unused. Oh well.
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Want to trade tanks? You can build these however you like? :D

btw Brad.... no update since July 2008?? Hurry up and pave the way man!! I might catch up! (yea right!) :D
 
LOL! I paid my dues with the sticky stuff, now you must pay yours. ;):D

Tell me about it. The good news is I am done with my recent training, so as of this week I am officially back into the airplane building biz. I spent yesterday taking care of a few honey-dos and cleaning up the garage, now all I have to do is figure out where I left off. :eek::p
 
I tried to get by with one quart of proseal but I was a bit scrimpy on the first tank and, you guessed it, I had a leak. Shipping costs to order two quarts at the same time is less than having to order twice.

I had tons of trouble making my own fuel pickup (just a regular, non-flopping kind), so it was well worth it when I finally broke down and ordered Van's premade pickups. I prefer their filter screen much better than cutting slits in the tube.

25' feet of corrugated tubing was plenty enough to do the wings. The tubing stretches as you pull it through (or maybe I should have drilled a larger hole). I had no problems pushing wires through it, so don't bother to run a string through it to pull wires through later. If you are going to put tubing in the fuse back to the tail, then go on and get 50' or, as suggested, get that irrigation tubing.

Unless you are an experienced tube bender and cutterer, order a bunch of extra aluminum fuel vent tubing. If you don't use the extra now, you can use it later.

Get a few extra AN fittings for the 1/4" and 3/8" lines. Again, if don't use them now, you will use them later. Order a few extra AN819 sleeves, too.

As for MEK, I actually used both acetone and MEK I got from either WalMart or Home Depot in gallon cans. MEK works a little better. Get a few hundred gloves and a couple rolls of high quality paper towels (I used some dollar store cheapies for a while and they were the pits). Proseal, to me, smells like sewer gas but got used to it and after a while you associate the smell with building an airplane. Just like the smell of avgas in the morning....it grows on you. Well, not really.


Have fun!
 
danielhv said:
So is there any pros/cons to having 2 flop tubes?
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I was going to install flop tubes... changed my mind as I'm not going to upside down for any extended period. You might review insurance policys on this issue too... :eek: A quick loop or a roll is all I need. :D

BTW... I have an extra roll of Van's wing conduit, I can mail it for $12.00 and save you shipping and handling cost on this item.
 
LifeofReiley said:
I was going to install flop tubes... changed my mind as I'm not going to upside down for any extended period. You might review insurance policys on this issue too... :eek: A quick loop or a roll is all I need. :D

BTW... I have an extra roll of Van's wing conduit, I can mail it for $12.00 and save you shipping and handling cost on this item.
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pm sent...
 
A "pro" that I see to two flop tubes (and fuel return plumbing), is resaleability. Having these leaves all options open. If you never use the flop tubes or fuel returns, you take a small weight penalty, but it is very close to CG, so the impact is minimal. I'd rather have the option to use them in the future without having to rebuild tanks, and I am sure many potential future buyers would prefer this over the small weight penalty.
 
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