[UnPossible]

Hey - the big day to insert the wings for the first time is here, and I'm having some troubles. When inserting both wings, I can't get the rear spar of the wing to go inbetween the two spars coming out of the fuselage.

As you can see in the pictures below, in both cases, the rear wing spar appears to be ~1/16 to 1/8" too far to the rear to fit into the slot. My dad and I fought it for nearly an hour before we gave up.... I have to be doing something wrong. Does anyone else have any suggestions as to how I can get the wings to mate with the fuselage (besides buying them a bottle of wine)?

Thanks,
Jason

Right Wing

Left Wing

 

[lorne green]

7 wings

As I've had my wings on and off, and on and off the past few weeks, Here's my hints. As the rear spar meets the twin attach bracket,
I used a large stotted screwdriver to separate the spacing bewteen two brackets. I've had to do this each time I've installed both wings (quick build)
Regards

 

[Mel]

From the pictures, it appears that you have the wings angled at a slight forward sweep. Try sweeping the wings slightly aft and inserting the aft spar first.

Also you might try inserting a spacer between the spar carry-through slightly increasing the space.

 

[Kyle Boatright]

As Mel <sorta> pointed out, you have to slide the wings straight in. Any angularity will cause the problem you see.

I lost a night of sleep back in the day wondering why one of my -6 wings just wouldn't fit. The next evening, it slid right in.

 

[VETE76]

From the pictures, it appears that you have the wings angled at a slight forward sweep. Try sweeping the wings slightly aft and inserting the aft spar first.

i agree, happened to me. straightened wing and they popped right in.

 

[AltonD]

Slotted screw driver, spread the rear spar just a little. Also, make sure your rear spar on the wing has been trimmed up per the drawing (38 I think).

BE REAL CAREFUL TO CLEAR THE BOTTOM FUSE OR YOU WILL BEND UP THE SKINS.

 

[Pat Stewart]

Aft Spar

I have built 3 RV's and helped put wings on a dozen others. A slotted screwdriver and a very slight opening of the rear spar was required on every one. Just the tolerence stack up at work, no big deal.

Pat Stewart

 

[Bavafa]

It also appears that you have not trim the rear spar on the wing yet. You need to trim some based on the measurement in the drawing. Once you trim it, if not already, it helps the wing swing back ward a bit more and fit easier into the slot.

Good luck

 

[UnPossible]

Well the slotted screwdriver did the trick. The wings are in and I have four hardware store bolt in on each side...... on to drilling the incidence.

Thanks again for your suggestions.

Jason

 

[Lionclaw]

It also appears that you have not trim the rear spar on the wing yet. You need to trim some based on the measurement in the drawing. Once you trim it, if not already, it helps the wing swing back ward a bit more and fit easier into the slot.

Good luck

^^^ Definately make sure this is done before you drill the rear spar attach points. I'd get some plumb-bobs off the front of the wings on a chalk or laser line as well to make sure the wings are in straight. On the 9A, the instructions also had me measure wing-tips to tail to check for equal distances. Once the rear spars are drilled there aren't any do-overs!

 

[UnPossible]

It also appears that you have not trim the rear spar on the wing yet. You need to trim some based on the measurement in the drawing. Once you trim it, if not already, it helps the wing swing back ward a bit more and fit easier into the slot.

Good luck

Nope - I have already trimmed the rear spar as per the plans (but thanks for mentioning this to make sure). I've hung the 4 plumb bobs and it looks like I may have a forward sweep of around 1/8" on each side...

 

[Mel]

Well, Yes and No! But not much!

Once the rear spars are drilled there aren't any do-overs!

If you initially drill the spars with 1/8" then recheck alignment, you will have a little wriggle room. It alignment if off slightly, you can "walk" the holes by filing before final drill to size.
Also remember that wing sweep is not super critical. You can have a small amount of forward or rearward sweep as long as both wings match.

 

[Pmerems]

Edge Distance on fuselage to wing overlap

Gents,

When setting and drilling the rear spar attach on my RV-7A I was very careful about minimizing the wing sweep. As was noted in another post that a little forward sweep was going to "hurt". However I found that with less then 1/16" of forward sweep I had less then desirable edge distance when drilling the last few screw holes in the fuselage bottom skin overlap to the wing.

I would recommend that if my parts are representative of the "standard" RV-7A parts that one should adjust the sweep to as near zero as possible to get more edge distance for the screws. If Van added an additional 1/8" to the overlap this wouldn't be an issue at all.

I believe I have .25" edge distance on the rear holes and .3125 on the forward holes. I would have preferred at least .3125 or more all the way around.

Food for thought, your mileage may vary.

 

[UnPossible]

Well, I'm going to sleep well tonight.... after several days of measuring and remeasuring, I drilled those two critical holes that sets the wing sweep and incidence. As you can see in the pic below, I was able to get the sweep to within a miniscule fraction of an inch. In each of my QB wings, I had roughly 1/10 of a degree of a difference between the incidence at the tip and the root.... nothing that I'm going to lose any sleep over. As far as the 5/8" edge distance, it was totally a non-factor.

Looking back, this is another of those tasks that I have dreaded when reading ahead in the builders manual, but really isn't a big deal once you jump in.... now how bad can that canopy be?