Sash bar dimensions for historical windows

[Jacob]

I’ve come across several examples of sash bar joints like this:

View attachment 164911

To me this looks like a joint that was made with a combination of a template and a sash coping gouge with a depth stop. It may not have been commonly done, being a “better” joint than the traditional mating method of sash bars, but more bother to do, and the customer can’t tell the difference. Being uncommon would explain the small number of sash coping gouges on the market these days.

Being a poor joint wouldn't help either! Why bother?

This is why I’m interested in the detail of these tools.

Never seen anything like it. That's probably the most complicated and difficult join possible! One very peculiar and bad detail here is the cut in the vertical glazing bar to accommodate the glazing fillet. It would weaken the vertical bar which is fundamental to the strength of sashes with very thin and delicate components.
Books are interesting but they tend to pick up the latest trends and can vary from edition to edition. Meanwhile your illiterate old joiner just keeps on bashing away just as his dad and grandad did, in a tried and tested traditional manner.

 

[Adam W.]

I thought you'd have a lot to say about it Jacob.

Have you ever considered that there might be other ways rather than just your way of doing things?

 

[Jacob]

I...

Have you ever considered that there might be other ways rather than just your way of doing things?

Of course, but the primary source has to be the evidence we have, in the examples we can look at, and in the tools left behind.
In any case this isn't "my" way of doing things I was taught this stuff quite specifically on a C&G carpentry and joinery course using hand tools only, with the long established and developed syllabus, derived from trade practices. But always open to better ways of doing things!
Not likely to find an old setting out rod of course , but they are well documented, easy to work and proven to be highly efficient.
In fact the rod, or full size layout drawing, was widely used through many crafts, in various forms, from dress making patterns to ship building (lofting floors, chalk lines etc).
The "story stick" seems to be an American thing.

 

[Adam W.]

It's just their name for a rod, you know how they like to be different after independence.

 

[Jacob]

It's just their name for a rod, you know how they like to be different after independence.

Not what he's using in the video. Also all the marking should be done in stacks on the bench, not item by item.

 

[Adam W.]

We used rods when marking out timber frames, they were always made from squared timber battens longer than the largest dimension of either the bay length or bay width with the o/o and all other dimensions struck on each edge. One edge for bay length, one for width, one for height and one for roof members. This method of using timber rods predates the use of full scale paper drawings.

It is a simple and accurate traditional method of marking out timber framed buildings and components from deep in our historic past and medieval examples have been found stored in roof spaces. They can be used anywhere without requiring framing floors to be constructed and maintained.

Edit:

That's probably why he's using a stick and not a drawing.

I'm pretty confident that masons would have been using similar techniques combined with wooden templets for stereotomy to set out large masonry buildings, as timber battens and templets are extremely durable and ideally suited to a workshop environment.

 

[toolsntat]

I think a specific "sash coping gouge" is just a tool makers speculative venture which very few people bothered with.
A normal 'incannel" gouge does it, mainly because nobody bothered with that difficult full scribed shoulder sometimes demonstrated. It's a machine joint.
Is "incannel" a real word or something recently made up?

All nomenclature has to have a beginning Jacob.
This reference in SMITHS KEY (price list) is likely to date 1821-1824.

 

[niall Y]

I have had a few goes at the alternative sash bar joint that @Steve 355 shows. It's not difficult . One of the components is cut. just as any halving joint is cut. The other is too, with the exception that, on this piece, the profile has to be scribed on both sides. This is done by first paring a mitre on the shoulders using a block and sharp chisel. The transition point between the moulding and slope, then gives you the outline of the shape to be scribed with gouge and chisel.

The downside of using this joint , is that both components are weakened. The wood left supporting each bar is only amounts to half the fillet left by the rebate. If you have multiple joints then you have to handle the bars with care. Also as the bars are full length, there is no opportunity to use up shorter pieces.

Edit. Duhh, my mistake............ Instead of saying "half the fillet" should have said "a1/3 and 2/3"

 

[Jacob]

We used rods when marking out timber frames, they were always made from squared timber battens longer than the largest dimension of either the bay length or bay width with the o/o and all other dimensions struck on each edge. One edge for bay length, one for width, one for height and one for roof members. This method of using timber rods predates the use of full scale paper drawings.

It is a simple and accurate traditional method of marking out timber framed buildings and components from deep in our historic past and medieval examples have been found stored in roof spaces. They can be used anywhere without requiring framing floors to be constructed and maintained.

I do exactly the same, as taught by experts! The board most likely would be a length of 6" white MFC chipboard but it could be real wood of course.
A window or door - two rods on the one board; a vertical and horizontal cross section. The elevation takes care of itself.
A chest of drawers might be 3 - vertical and horizontal section of front and one section of one side, as necessary
Every detail marked including clearance gaps.
Components then stacked and marked from the rod with a set square and 2H pencil, then marked around all 4 sides of each piece. No knife involved

That's probably why he's using a stick and not a drawing.

He doesn't know what he is doing. It'd take ages fiddling about like that and errors would be made and could accumulate

I'm pretty confident that masons would have been using similar techniques combined with wooden templets for stereotomy to set out large masonry buildings, as timber battens and templets are extremely durable and ideally suited to a workshop environment.

Definitely. It's hardly a new idea. In fact it enables precision work without reference to any standard measurements or calculations.

PS - Rods on paper. I'm told that shop fitters sometimes would get a paper rod, rolled up, ready to spread out on the floor and to work from directly

 

[Jacob]

he downside of using this joint , is that both components are weakened.

Exactly. And it's much more difficult and time consuming.

... Also as the bars are full length, there is no opportunity to use up shorter pieces.

The method is to mark up all the bars as full length but then cut the horizontals at each centre mark of the crossover - the end of each of the stub tenons, though not before you've sawn an X across the moulding, to be scribed (coping saw), and a slot in the glazing fillet for the vertical bar to go through. It's a lot less work than marking each short section individually, which won't save much timber anyway, unless you are desperate.
PS side hung casement windows t'other way - the horizontals go through and verticals cut

 

[Jacob]

I’ve come across several examples of sash bar joints like this:

View attachment 164911

To me this looks like a joint that was made with a combination of a template and a sash coping gouge with a depth stop. It may not have been commonly done, being a “better” joint than the traditional mating method of sash bars, but more bother to do, and the customer can’t tell the difference. Being uncommon would explain the small number of sash coping gouges on the market these days.

This is why I’m interested in the detail of these tools.

Just a thought - the joint above would allow you to drop in the short lengths of glazing bar between the already fixed verticals. One way of doing it, not a good way, but maybe that's the (imaginary) problem the author was hoping to solve?

 

[johnnyb]

you must try to make one. it's like someone's switched on a light. they had a depth stop so you knew how much of the moulding to leave entering the scribe. nothing is worse than something not clicking together because your not quite deep enough.
early stuff was also dowelled on the thin bars.

 

[Jacob]

you must try to make one. it's like someone's switched on a light. they had a depth stop so you knew how much of the moulding to leave entering the scribe. nothing is worse than something not clicking together because your not quite deep enough.

I might have a go, if I ever do another bloody sash window.

early stuff was also dowelled on the thin bars.

Occasionally - but top end stuff only? A thin dowel joining the cut ends of the horizontal bars, perhaps boxwood. Belt and braces?

 

[Jacob]

Another idle thought. You occasionally come across old specialised fancy tools, these "sash" tools, wooden planes with fences etc. still in good condition. Is this because they were not used much, possibly useless?
Compare contrast e.g. Stanley 78 - often available heavily bashed about with parts missing, precisely because they were heavily used and immensely useful?

 

[johnnyb]

on a side note I was searching for the episode of Tommy walshs space invaders where Jacob help him sort a sash window out. no longer on youtube unfortuneatly....

 

[Jacob]

on a side note I was searching for the episode of Tommy walshs space invaders where Jacob help him sort a sash window out. no longer on youtube unfortuneatly....

That was some years ago. I forgotten all about it. I thought it might lead to TV career - me as the "Rick Stein of windows" but it was not to be! All good fun at the time.

 

[johnnyb]

I seem to recall you were hilariously short tempered with old Tommy. we know your not really grouchy...or have you mellowed?

 

[johnnyb]

ps you were more like the Gordon Ramsey of windows xx

 

[johnnyb]

could you tell us any stories about that episode Mr b? what was tommy like? it was in a peak cottage but not the episode about sash windows.

 

[Adam W.]

I do exactly the same, as taught by experts! The board most likely would be a length of 6" white MFC chipboard but it could be real wood of course.
A window or door - two rods on the one board; a vertical and horizontal cross section. The elevation takes care of itself.
A chest of drawers might be 3 - vertical and horizontal section of front and one section of one side, as necessary
Every detail marked including clearance gaps.
Components then stacked and marked from the rod with a set square and 2H pencil, then marked around all 4 sides of each piece. No knife involved

He doesn't know what he is doing. It'd take ages fiddling about like that and errors would be made and could accumulate

Definitely. It's hardly a new idea. In fact it enables precision work without reference to any standard measurements or calculations.

PS - Rods on paper. I'm told that shop fitters sometimes would get a paper rod, rolled up, ready to spread out on the floor and to work from directly

My bold.

I think you are being unduly harsh on the man. He may be doing it that way because he's making a video and being directed by a photographer.