Landing gear?

Jimzim · #1 05-11-2011, 06:46 AM

Fuse coming along, any reason not to mount the gear legs and engine mount now? Plans call for wings temporarily attached first, but that makes no sense to me. What am I missing?
Thanks for input!

schristo@mac.com · #2 05-11-2011, 07:00 AM

the gear gets in the way for directly measuring sweep of the wings but you can easily measure with an offset.

cjensen · #3 05-11-2011, 07:37 AM

If you plan to fit the wings with the gear on, it's gonna be more difficult to slide the wings in at an angle. It's fine to fit the gear to the mount, but remove them to fit the wings...you can leave the engine mount on, it's not gonna be in the way.

KayS · #4 05-11-2011, 07:39 AM

you can attach-drill the wings at the end of the project. i think more important is that you drilled as many necessary holes as possible in the firewall before bolting on the engine mount.

drilling the firewall without the engine mount is much more easy.

Kay

cjensen · #5 05-11-2011, 07:42 AM

Absolutely correct Kay...just to clarify my post, I was speaking only about the mount not being in the way for fitting the wings.

N1Flyer · #6 05-11-2011, 06:43 PM

Does the method suggested, wings installation before gear installation, apply to the -7A. The gear doesn't appear to be a problem on the A, but I would yield to someone with experience.

Thanks in advance for the help.

Rick

Jimzim · #7 05-12-2011, 07:19 AM

Thanks to all for the help. Sounds like I had best fit the wings before the gear with an eye toward having the firewall drilled as much as possible. I have the holes drilled per the plans for my engine/carb choice, but I best look ahead to what all else will mount or penetrate the firewall.
With my very limited space in the garage, I'll probably need to trailer the fuse 40 miles to the hangar to fit the wings and then bring it back home to continue. I guess I'll need to support the first wing with a stand until they are both on, then go ahead and fit them. I couldn't find anyplace in the plans where it specifically says to go ahead and mount the gear, but I'll follow your advice. I must admit I'm anxious to get it up on it's feet and hang the engine, but no need to make it more difficult...
Thanks for the help!

schristo@mac.com · #8 05-12-2011, 07:25 AM

not worth the effort / risk of an extra transport to and from the airport just to fit the wings now... consider differing fitting the wings until you do the move for good.

BSwayze · #9 05-13-2011, 06:05 PM

Quote:

Originally Posted by N1Flyer

Does the method suggested, wings installation before gear installation, apply to the -7A. The gear doesn't appear to be a problem on the A, but I would yield to someone with experience.

Thanks in advance for the help.

Rick

Rick,

I know a lot of 7A builders install the gear leg weldments as the fuselage is being constructed. No problem there. I drilled the gear legs before installing the weldments in the fuse for good. This takes place early on.

As far as putting the airplane on the gear before mating the wings, I see two possible issues. One, it will sit up a lot higher, making it much harder to reach inside for all the work that remains inside the cabin and forward fuselage. Not to mention all the work on the canopy. Plus, you'll have to have the third leg, meaning the engine mount and front gear leg installed. Are you ready for all that yet? Note previous comments re: holes in firewall, etc. Either that or a really high support for the tail end. Balancing issues come to mind as well.

Second, mating the wings carefully requires leveling the fuselage across the longerons and front-to-rear as well. How are you going to do that when it's on its' gear? Shimming up one side or the other seems to me to me to be much easier with it on a crate, sawhorse, or jig as during construction.

Every RV I've ever seen that's on its' gear can be easily rocked back & forth sitting there on rubber tires. Not the best scenario for the precision leveling and solidity needed for the wing mating. For all these reasons, I'd wait.

Flying Scotsman · #10 05-14-2011, 12:41 AM

Not to say anyone else is wrong, but I had my 7A on the gear when we installed the wings for the first time (to drill the aft spar holes). Everything was leveled to within the capability of the digital level. In fact, adding or letting air out of one tire or another was used to get it as close to absolute level as possible in the lateral axis. Longitudinal level was just as easy.

After drilling the wing spars and locking them in, the empennage was installed and similarly leveled, including a thin shim on one side. Water levels on wings and tail ensured that wings and horizontal stabilizer were perfectly matched.

Piece of cake (ha ha!).

Biggest plus for having the gear installed was that we could move the plane easily to wherever we wanted to work (in this case, from the garage, where the wings wouldn't fit, to the rear patio, where they would).

Steve