My friend bought a brandy new ASG-29, it's beautiful! It's German, which means close tolerances and tight fits. The wings are a real bear to get on even though he's waxed the spars. Someone suggested flying near a thunderstorm for an hour or so, the incredible turbulence would loosen thing up, he's not ready for that.
Install the wings and there are two pins, each 35mm diameter (~1 3/8") that pass through both spars locking them in place. Pulling the wings in the last 64th of an inch to get the pins in is a PITA, one website suggests using a wooden dowel to pull the wings together, but the dowel has to be so short there's no leverage. I was thinking of two cylinders on a common rod, each cylinder offset but can be pulled to center by rotating the rod. There are two pins, use one hole to pull them in and then pin the other hole. Expandable mandrel? Pulls the wing spars together, then put a pin in.
Some ships have steel anchor pins poking out of the top, a tool is supplied that pulls the two together, not legal in this case and I don't know if drill holes through the bones of your wing is a good idea.
Suggestions?
Similar pin hole:
ASG-29.
The cam idea sounds easy and relatively safe. I'm thinking an oval piece (longer side being equal to the diameter of the pin) with a 1/2" square drive socket in it so you can operate it with any socket wrench. You put the cam in so that the length of it is parallel to the fuselage and then rotate it 90 degrees to pull the wing in that last bit. Only problem is that it might cause wear on the bore. Would using lubrication there be a bad idea? Maybe you could put rollers at the tips of the oval?
With the expandable mandrel you wouldn't have to worry about wear, but that could cost money that even a sailplane pilot would think twice about.
It might very well loosen up after the airframe's been put through some stress, maybe some aerobatics? 
On the MQ-9's we had 4 tapered pins which operated as you described to install the wings. Usually we'd just lubricate them with some anti-seize, setup the wing fixtures, and the make minute 3d adjustments to the fixtures until things aligned.
My junior guys would always misalign the pins then break out the slide hammer to make things worse before coming to get me. It works under some circumstances but I've generally found it to be a bad idea.
Usually when things didn't align it was due to the wing being slightly too far forward or rearward and they just needed to be rocked. Wing jacks and cradles make that a lot easier but GSE is really expensive.
Maybe make taper a pin, set one side, install other side, pull out the tapered pin, and install the remaining side?
The expandable mandrel or a piece of regular thread and reverse thread stock with a barrel in the center to pull both sides inward would work too if you have the access. I forget what those barrels are called, they operate like a turnbuckle, but I've used them before.
So does it work like this? hard to picture this assembly..
Same pin but it sits in a well behind the seat. No push rod, but not much room to finangle.
Those are wings. I'm not sure I'd be messing with anything designed to keep them in place. Wing-o eject-o mod isn't advised. Unless he's looking for a lawn dart.
In reply to Appleseed :
I assume he's looking to pull the wing bushings into alignment with the spar box bushings rather than perform an illegal modification.
There's not a whole lot of data on these on the FAA's website. I was wondering if there was an STC which detailed the external skin/spar modification you asked about.
There are Google Groups that address this on many models of glider, basically a pin .010 smaller than standard with a slight taper is put into one hole aligning the second. Put the factory pin in the aligned hole, remove the "assembly pin" and put in the second factory pin.
I think the biggest problem is the ship is brand new, tight.
Thanks for the help, will let you know how it ends.
Dan
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