RV-12 wing pins tight

Have finished my RV12 except for the avionics Putting on the seal between wing and fuselage The wing fits so tight that it takes a rubber hammer to
start the pins they come out all right and go back in as long as you don't pull out the wing or you use the rubber hammer again Is this common or do I just have too tight of fit They went on about the same way before I installed the wing seal Also my top Colling fits real tight hard to get the hinge pins in

re: Wing pins

If you search the archives, you'll see that this is very common. I also use a big rubber mallet but am thinking about buying a pipe expander as explained in one of the posts when the wings come off for painting.

Copwl hinge pins are a bear-- they do wear in with use and Boelube PASTE applied each time you put them in will help. Same for the wing pins.

Wayne 120241 N143WM

Another way

Have you tried "winching" the wings together using luggage straps as described elsewhere (attached to the tie-down rings)? My UK inspector frowns, but it works every time for me.

Cheers...Keith

Another Winch Method

Last time, attached a medium sized C-clamp to the top of each spar inside the fuselage on the left and right sides. Then used a luggage strap to winch them together. Worked well and did not mark the spar.

Fortunately my friend Bill at the FBO has a fully equipped machine shop. He made a "bullet" for me to use in getting the spar openings aligned. Once the "bullet" is in place, one can just insert the pin behind it and tap it in with a soft-faced hammer. The bullet is short enough that it goes right on through and falls out the back side of the spar. I seem to recall that another builder had one of these made - I think it was John Bender.

See here: http://www.mykitlog.com/users/display_log.php?user=BigJohn&project=639&category=0&log=120084&row=35

and

here: http://www.mykitlog.com/users/display_log.php?user=BigJohn&project=639&category=0&log=123812&row=6

Is there a better wy?

So is there a better way - maybe an engineering change or???
I don't want to fight my wings on and off each time I fly. There must be a better way than just leaving my 12 in a hanger somewhere.

Can someone tell me why everyone is having so much trouble. The two man demo on Van's website makes it look pretty easy. What's up?

Installing wings

The two-man demo on Van's website makes it look pretty easy. What's up?

Click to expand...

I bet they had lots of practice before making the movie. And was the gasket installed at the wing root?

So is there a better way - maybe an engineering change or???

Click to expand...

Some more nylon blocks could be installed so that the spars holes will have to line up both vertically and fore and aft. Then the only challenge will be inserting the spars deep enough into the fuselage and to compress the gasket and line up the holes from side to side.
Here is a link to another thread on this subject:
http://www.vansairforce.com/community/showthread.php?t=47846&page=2
Some others have expressed concern that the pipe expander will damage the brass bushings. I think that the hammer and tapered pin method will do more damage because there is relative motion between the pin and bushings. The pipe expander has very little relative motion between itself and the bushings because all of the wedge action takes place inside of the tool.
The ratcheting strap method works well too. The straps can be attached to the tie-down rings on the bottom of the wing and through the wingtip hand hole and over the cockpit to the other wing. Or instead of using tie-down rings, longer straps can go under the fuselage.
Joe

I had this talk with Van himself at Sun-n-Fun last year and he said that what we were doing wrong was that we were not trimming the wing root wing skins so that they had at least 1/8 " clearance all the way around. I would have done this but the aircraft was already painted and I did not want to make a mess of the wing root. It has still not made it into the plans so I guess we must just read Ken's mind on the subject.

The material I used was from Home Depot, it is the MD brand, High Density Foam Tape Weatherstrip, the size is 3/16" thick x 3/8" wide x 17' long. I used the white color and it comes with two rolls in the package which is plenty to do both sides of the plane. The aircraft is hangared and I see no indication of any change in the material after six months so it would seem to hold up well and at about $ 2 per package it is cheap to replace.

I start with the wings on and run a 1/8" masking tape line around the wing root even with the wing skin on the fuselage. I then remove the wings and place a second 1/8" tape line outside and against the first tape line. Then remove the first masking tape line and place the foam tape to match the inside of the second masking tape line. Remove the second masking tape line and replace the wings and let sit for 24 hours or so so that the foam tape will have some clamping pressure to keep it in place while the tape bond develops.

I might add that my wings fit with only 1/8" or less gap between the wing and the fuselage if your gap is wider by much you may need thicker foam tape and it is available.

Good luck, hope this helps.

Best regards,
Vern

30-03 Step 4

Good point Vern, about that 1/8" gap. It is hard to compress that seal. Van's has come out with a revision about that gap: 30-03 Step 4
Joe

MartySantic said:

Last time, attached a medium sized C-clamp to the top of each spar inside the fuselage on the left and right sides. Then used a luggage strap to winch them together. Worked well and did not mark the spar.

Click to expand...

Great tip Marty! Quite easy with the luggage strap to get the pins in.

This is much easier, and works swell: http://www.mykitlog.com/users/displ...TX&project=1903&category=0&log=132412&row=160

This also works 100%. Stick the wings in, slide this in and tighten it up, push the other pin in, remove the tool and slide the other pin in and you are done.

http://www.harborfreight.com/small-tail-pipe-expander-69550.html

The Plowboy spar aligning tool, by Dave12

Dave12 said:

This also works 100%. Stick the wings in, slide this in and tighten it up, push the other pin in, remove the tool and slide the other pin in and you are done.

http://www.harborfreight.com/small-tail-pipe-expander-69550.html

Click to expand...

Dave, You beat me to the reply. Dave's expander makes installing the wing spars a non event.

Mine were tough initially. I trimmed the wing skin, used rubber C-channel instead of the foam seal and applied a light coat of axle grease. I still needed to tap them in. At my first annual they went in much easier, so I think the parts do adjust themselves slightly with use.

Pipe Expander

The Harbor freight Expander works just fine. I can't believe it causes anywhere near as much wear as pounding the pins in (and out) with a mallet

Wayne 120241/143WM

DonFromTX said:

This is much easier, and works swell: http://www.mykitlog.com/users/displ...TX&project=1903&category=0&log=132412&row=160

Click to expand...

Don, this is a great idea. In fact, Van's should machine the standard pins in that manner.

The actual pins are just a hollow pipe, so that would be hard to do, but maybe a great idea. Making the tool only takes a few minutes, costs nothing if you can scrounge up a piece of aluminum rod and borrow a lathe.
I dreamed up the idea after I saw a popular blue RV12 at Oshkosh, use a fair sized hammer to beat the pins into the spars during a wing removal demonstration. Did not want to do that on mine.