Fuel Tank to Wing Attachment

I'm at the point in left wing construction where I can start riveting the top skin. Van's instructions say to attach the fuel tank with a "few" screws/bolts, and as far as I can tell does not mention the fuel tank attachment again in his instructions. The fuel tank is complete and has been pressure tested. It seems to me that this would be the best time to insert all the tank bolts mounting the tank to the main spar and torquing them to specifications. Doing so after the top and bottom wing skins are riveted would be more difficult. Even with good access I had a difficult time starting some of these bolts. Would appreciate any comments.
Thanks, Frank Bush

I bolted mine....

....down for good, then went about riveting the skins on.

A quick tip

Before you put the tank on permanently, check the gap (or lack of) between the tank and the outer leading edge skin. ie where they meet. It is very tight. I recommend block sanding the outer edge skin on the tank to obtain a 1/32" gap between the tank and the wing skin for paint. This especially important if you are going to paint the tank separately. Even if you are not, you should establish a gap in the event you have to remove the tank.

Sand, fit, repeat as necessary, deburr and scotch brite. Takes less than 30 minutes a tank.

I see no harm in bolting the tank down now. Your right about not having much room. I waited until the skins were on to finish bolting the tank and it wasn't easy, but doable.

It was much easier installing the bolts for the tanks with the skins off. A couple of the holes were off a bit and had to struggle to get the bolt threaded. Having the tanks on, had no effect on installing the wing skins.

Fully assembled and clecoed...

When I built my wings in 2003, I did a full assembly with clecoes of all the skins, and bolted the tanks in place as I would after all riveting was finished. This practice run through of the assembly let me see all the issues.

You can see who I did it by looking at my web site beginning on this page:
http://www.n2prise.org/rv9a006.htm

Some very valid points. Thanks for all of your comments. Will complete the tank attachment before riveting the skins.
Frank Bush

I may be a little late weighing in but...I bolted the tank in place with my first wing and had no problem shooting rivets with an assistant. With the second wing, I left it off while riveting the top skins and found that simply by reaching over the top of the spar I could shoot every rivet by myself! If you have a regular assistant - attach the tank now; if you're building mostly by yourself - consider leaving it off while you attach the top skins.

Good luck!

Re: Tank to Wing attachment

Thanks for your comment Fred. Getting a second person to help is an issue right now with the holidays coming up. I've decided to pull the tank for now. The tank to leading edge fit is tight and per another's recommendation I'll block sand to achieve a 1/32 gap. Also need to countersink some of the tank screw attachments on the spar a little deeper to get a little closer skin to spar fit.
Frank Bush