[ soundtrack : De Press - ‘Bo jo cie kochom’ (1981) ]
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This post isn’t too long for mail — knock yourself out!
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I’m working on a set of windows of a kind I don’t know the English word for, using a type of hinges I’m not sure what to call. It would be so much easier for me if you just learned Norwegian ;-)
No? OK. I’ll try to explain: I’ll call them ‘winter-windows’ because they are auxiliary glass-frames that can be lifted off and stored in the warmer seasons. The salient point here is that they have a ‘lip’ that shuts tight against the casement, like so:
This means you cannot use a flat butt hinge, but must use bent or ‘cranked’ (?) hinges that can fit in the corner of the rebate.
Or you can use a type that’s more common in Continental Europe which I think is called fiche hinges (Norwegian: ‘innstikkshengsler’ - literally ‘stick-in-hinges’. I’ve said it before; Germanic compound nouns have a brutal beauty all of their own :-) Traditionally they are used on rebated doors and windows with the wider leaf mortised into the edge of the door under the lip and the narrower leaf into the front of the face frame.
These kind of hinges are not let into a shallow recesses like ‘normal’ hinges, but are stuck into a narrow slot:
The advantage of these kinds of hinges & rebated frames is that they are seemingly more dust-proof / airtight. But the real advantage, in my opinion, is fiche hinges in combination with sealing strips to make things properly airtight. The fiche hinge leaves an unobstructed run for the sealing strip to do its thing. The first step towards keeping warm in winter is to stop the draughts!
The difficulty lies in making that narrow slot to house the hinge leaf. Previously I used to drill a row of 2 mm holes that I would attempt to clear out with my narrowest chisel (2 mm) and a silly Tiger’s Tongue Chisel (that not only is one millimetre too thick, but also does not work at all).
I got it to work after a fashion (packing the slot with a piece of veneer to snug up the hinge leaf), but it took bloody ages! Acceptable if you’re doing a window or two, but that’s the limit for this technique.
There used to be specialized bench-mounted machines, a bit like a morticer, but with an oscillating sawblade that had its teeth on the bottom, that would cut narrow slots for hinges like this, but they are very difficult to get hold of these days (and I don’t use these kinds of hinges that often).
On this job, I’m only using 21 hinges, but with two leaves each, that makes for 42 slots. I obviously had to up my game, so I thought I might try using a ‘Fein-saw’ — a type of oscillating saw that can make plunge cuts, leaving narrow notches; popular with carpenters. I borrowed one to try out:
It seemed to work well enough, so I gave the proper parts the same treatment:
The sawblade is 1 mm thick and I need a slot measuring 2 mm, but with underlays of appropriate thicknesses I was able to freehand it with pretty good results :-)
But before I did this sawing-gnawing out, I took the time to drill the holes for the hinge-screws — cleaner results doing it beforehand. Brad point drill bit finds the spot exactly …
… before the thicker, normal drill enlarges the hole you’ve just made to accommodate the shank of the screw. Best if you don’t hold on too tightly to begin with; lowering the conical tip gingerly, letting it center itself before you plunge it — depth-stop engaged, of course! It’s the sum of all these small things that makes a big difference :-)
After a quick clean-up with my vintage 2 mm chisel [ breathes on finger nails and polishes them on lapel — before admiring them lovingly ] …
… that part of the job was done …
… leaving only the rest for another day.
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In the US we would consider these a type of “storm sash”. We have a few traditional designs. Most are designed to sit against the blind stop (which holds in the upper sash of a double-hung window) and within the external casing. The “Eastern style” doesn’t have a blind stop and so (as I understand it) the storm sash includes this rebate/rabbet to allow the storm sash to seal against the casing.
Do these extra windows act a bit like double glazing and add extra insulation