Hi, we have these windows in our house - from the mid 80's - so over 30 years old, excellent quality, the wood is still in great condition. They're the kind you can pivot almost all the way round so you can wash the outside from indoors. I've posted two photos. All have now dropped slightly so the end furthest from the "hinge" scrapes on closing. They don't really have a hinge as such, they glide along inside a top and bottom runner, bit like a scalextric car. I'd like to restore them if poss. Has anyone done this? Is it a case of changing the fittings? Or maybe they've done their job, and new ones are needed?

No, I'd say more of the weight is on the bottom channel, a photo of which I was unable to upload, but I think I may now have succeeded. The house is a wooden Swedish thing, so I don't think the head has sagged, but I will check.

Is there a manufacturer's name on the hardware somewhere? It looks like there might be one shown in your second photo. If so, I would contact them and ask them about maintenance and adjustment. They probably have a manual and have probably dealt with the question a thousand times.

If there's no name, I'd show photos to local window fitters or shops. Somebody will recognize them.

Posted By: minisaurusAll have now dropped slightly so the end furthest from the "hinge" scrapes on closing.

If you put the windows at the point where they just start to scrape and then lift the outboard end of the window you may be able to detect where the play is that has caused the drop. And determining this may point to the remedial action.