Restoring 4 x carimate  

First step is to remove the paint by chemical stripping. Then it should be evident the type/quality of wood and whether or not it would be worth your while to take it further to a "natural" finish, restore original color, or go in another direction. It seems the colored lacquer versions of these were often beech, FWIW.

If the wood was sealed before the red lacquer or paint was applied, it might work. But if not, then the red pigment in the finish might have stained the wood deeply enough that you'd have to sand it.

Those chairs from Amsterdam modern with the desired look are executed in pine. Good god.

Let's be fair to pine, Leif! it gets a bad rap, for sure amongst some aficionados here, but good grades are entirely appropriate choices for quality furniture designed for its use and these chairs are, arguably, a good example.
Can you tell I've had my coffee this morning?

The armrests on these chairs are narrow with a sharp edge on either side. Guaranteed to get completely have a pockmarked, dinged surface too, too fast. The colored versions of the chair would have been done in beech because a pine surface would ding easily and deeply, and break the paint or lacquer surface, resulting in an even uglier ding.
Mogensen designed some pine furniture once. The reviews pointed out specifically that everything was thicker, with very rounded edges to accommodate the soft wood. It was definitely not Mogensen's finest work.

Well, Leif, some people do have sharp elbows, I suppose.

And tables have hard edges.

Mating chairs and tables is too complicated!

Thanks for the insight all. Is suspect mine are indeed in beech.
I contacted a sandblasting compay and they won't do the job because of the double layer of paint. I'll do the chemical stripping and think of a nice matching color. Originally they came in white, black and red?

pics

You could stain the beech. Beech actually has amazing grain that shows pine like contrast if you apply a tinted Danish oil finish. (Other stains, which the Danes usually used on beech are much more opaque and hide the grain).

Here you can see a beech chair finished with a tinted oil that highlights the Rays in the grain of beech:
http://www.designaddict.com/forum/General-discussion/Ole-Wanscher-wood-I...