Hans Wegner CH-34s + a pair of unknown side chairs  

Tktoo: I have no idea what Carl Hansen specifically used for cross dowels for screw/bolts going into end grain. Sometimes the Danes would put in a wooden cross dowel and send a screw with wood threads straight into the cross dowel. This is a bit quick and dirty, and not so common. Usually I have seen a threaded insert (machine threads on the inside, deep screw threads on the outside) sunk into the cross dowel.
Carl Hansen used a particularly wide cross dowel. A "cross slat" really. Maybe there would be a T nut in there (hollow shaft, machine threads inside, smooth outside, with a wide metal flange on the back end and teeth on the flange). This is my guess. There are two advantages of a T nut over a square nut: 1. the recess for a T nut, being circular, can be simply created with a drill press, while a square nut would require a square mortise, cut with a chisel by hand or a mortiser. 2. The alignment of the bolt threads with the hole is guaranteed with a T nut because the threaded hollow shaft drops into the hole for the bolt, while a square nut would require very precise work creating a square recess exactly centered over the hole.
Not that any of this matters anyway. It is so far off into the weeds as to be pointless. But I've drilled holes and recesses for, and pounded in, literally thousands of T nuts in my life, so I have a certain grudging respect for the utility of the funny little things.
Oh, and they really look wonderful. I am glad to see such nice pieces so respectfully restored and looking so sharp. Pumpkin leather looks fantastic to me.

Leif, we could really get into this in a big way, but that would hijack the thread unnecessarily. If I had a burner account, I'd post an address and we'd sure have some fun.
The focus should be on teakhound's fantastic rehab work. Appropriate apologies offered.

No my apologies. The focus absolutely should be on this very nice restoration.
I just recently found a good substitute for the black fabric tape the Danes used to cover the staples on the southbound end of chairs. Black fabric gaffer tape. Sold simply as gaffer tape to the movie business. . It is available in a wide variety of widths too. And in my little cow town, thanks to a blooming of the movie/television industry, it is rather easy to find. Certainly available with some digging elsewhere too It is such a good substitute, I am not quite certain it isn't the real thing.
And Tktoo: I can be found here: http://movablemodern.com/contact

compliments to you, teakhound, or whoever the upholsterer was if not you.

tktoo – I realize my less than precise language re the 'inserts.' The truth is, I don't know what's in there, but the whole construction was very elegant. You may well be right about the square nut, as it sounds like something may be shaking around in there...
Just bought a sweet little pneumatic stapler, so I thought I would try my hand at upholstering these. Thank you all for the kind words 🙂
Lief – Thank you for the note on Gaffer tape. I am on it!
And don't worry about straying off topic or this any other thread – I always learn a tremendous amount from ( or am at least greatly entertained by) banter on this forum.

Well now I'm even more impressed! Have you done much upholstery before this?
Pneumatic staplers are THE BEST. Mine is the single most worthwhile, wonderful, valuable, indispensable tool I own. I would marry it if such a thing was legal.

yeah, with all of the progress photos, I thought you probably did it yourself, but it wasn't noted either way in the update.
very impressive.

And as tempted as I was to show my shorts today (not to mention last evenings fabulous dinner attire)... I didn't. The chairs are much more impressive. But I did learn a new naughty limerick, and also have noticed that the intelligent turkey's in my county are nervous. And I couldn't locate one handsome Pilgrim in any online photograph. not one. Most of them look like Appalachian Americans. I do like their shoes however.
Hi,
Aunt Mark
ps again, very nice work.