upholstery of a moller chair..  

it is what ever
your heart tells you to do.
if you choose a fabric that compliments the chair then go for it.
If you choose a fabric because it's cheap then don't.
Always look at the martindale abbrasion rating for the fabric and choose one over 30000 as others are curtain fabric and will not last.
picture of some i did in brown leather

Thanks for the leads,...
Thanks for the leads, Simon.
In fact what I'm looking for is some guidance in the proces of upholstering these. As your example shows, I'm contemplating leather.
Only thing is, I can't find a scource wich tells me the materials and technique used:
singles, foam, padding... how it's done around the legs etc.

I've redone a few of these. ...
I've redone a few of these. They have jute webbing stretched taut over the frame and stapled on the underside. There is thin foam over that---like 1/2" thick? Maybe 1.5 cm? (Hard to know because it's always compressed on the old ones.) The foam should wrap around the sides of the chair seat. It will get compressed to a thin layer on the sides once the leather is pulled tightly and stapled.
The easiest way to cut new leather is to use the old vinyl or fabric as a pattern, but if you have only the naked frames, obviously that won't work.
Basically you cut a piece of leather that is big enough to wrap around the sides with some extra to hold while you pull it taut for stapling. You want about 3"/8cm extra on each side.
Staple the leather in place with a few staples on each side, stretching it taut as you go. Do front-back first, then side-side.
Fitting around the leg posts is pretty easy (see diagram). Leave about 3/4"/1.5cm extra around each post and make slits in the curve CLOSE to the fold line but not quite touching it. Practice this on scraps of leather. The spacing of the slits will depend on the flexibility of your particular leather.
Leave the same amount of extra down the sides of the cut edges.
Tuck these cut edges under to fit snugly around the posts.
Continue stapling, alternating sides so that you don't get it out of whack. This is important with leather because it can tear if you have to remove staples to get the tension right. The tension should be very even on all sides.
Trim the leather close to the staples when finished. Staple a dust cover (thin black fabric, either woven or non-woven synthetic). Done!

Well you learn
Something new every day.
The mothed is not now to me but similar.
I cut the leather and use joinery clamps to hold it in place while i cut and staple the corners.
I always cut from the point into the leather so that i fold triangles under and the leather fits snugly to the leg when pulled tight.
Normal staples required for the leather fits is 3 in each corner.
Once all the corner are done the side fron and back rails take minutes to complete.

that's very straightforward...
that's very straightforward and usefull info, spanky, thanks a bunch!
these are the ones I have, with original (but worn out) flat braid.

I will be interested to see...
I will be interested to see how your black Moller chairs turn out. I still have the ten I got more than a year ago, and have had no time to do anything with them yet.
It is most likely I will do corded seats, but if you do leather or vinyl I hope you post some pics of the final result. It would certainly be easier for me to replace the upholstery than it would be to tear everything off and put in the nails so I can cord them, as jesgord had to do with his.

so, simon, when you tuck...
so, simon, when you tuck these triangles under, do you slide them under the foam, so they don't press through the leather?
I know you once adviced on how to laquer these black, acid cat or something, can you elaborate on that?
yeah, tchp, I have several black chairs (3 different sets or so) and a rather big table. I'm thinking of mixing these chairs all together around the table.

the leather
is not tucked under but I do trim it down to 1.5cm.
I always trim the foam around the leg to 2cm gap so it looks the same even with the leather tucked under.
Acid cat laquer is the best result and should always be done by a professional otherwise you end up with a terrible result!!

tchp
I redid one chair in vinyl to match others in a set and I have to say, vinyl is much harder to work with than leather, at least in the weight that I used (which seemed kind of heavy). When you stretch it, it does not stay stretched, it goes right back. And it tears very easily, so you have to get the tension exactly right because do-overs with the staples are risky. Leather is much more forgiving.

Thanks spanky. I would not h...
Thanks spanky. I would not have realized that. I am still on the fence, but I expect that in the end I will go with cord, since I like the look and it is probably the most cost effective solution for doing ten chairs. And besides, I already have a box of 1000+ Danish nails and a "Berry's Stapler Removal Tool" that is dying to be put to use.

bj
In the process of removing the fabric from my chairs, I measured the thickness of the foam that was used, and it measures precisely 1.5cm in thickness.

thanks for the info, tchp!
thanks for the info, tchp!

I took several photos also,...
I took several photos also, to give an idea of how things are layered. This shows the staples on the fabric. This chair has far fewer staples than the previous four I did, as it was made by a different person at a different time.

The foam, applied to the...
The foam, applied to the bottom edge of the wood stretchers with contact adhesive, then trimmed at an angle to create a smooth taper.