Sash bar dimensions for historical windows

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As Jacob pointed out the picture I shared above was actually a “franked” tenon. t has a “negative haunch”. All of the joinery books circa 1900 show this as the main joint for window sashes. I was asking if there was a method to cutting it as it wasn’t immediately obviously to me.
Hi Steve. I always Frank my sashes. It gives a longer baring surface for the wedge to sit against, and contrary to what others may say, every old window I have examined, including many examples in the Brooking collection, are done this way. In my workshop, I remove the portion of the franking on the mortiser, but when doing it by hand, I would use a firmer chisel and mallet after cutting the majority away with a tenon saw.
 
Hi Steve. I always Frank my sashes. It gives a longer baring surface for the wedge to sit against, and contrary to what others may say, every old window I have examined, including many examples in the Brooking collection, are done this way. In my workshop, I remove the portion of the franking on the mortiser, but when doing it by hand, I would use a firmer chisel and mallet after cutting the majority away with a tenon saw.
The plot thickens!
According to Greenhalgh/Corkhill/Lowsley (2nd edition 1946) the franked joint is for "fast" sheets, i.e. fixed lights with no frame, which is an unfamiliar object as far as I am concerned. It says it's supposed to keep water away from the mortice but I can't quite see how. Not particularly mentioned with respect to sliding sashes
Fashions change, Ellis 1902 is late and 1946 is even later and some fashions were very different. It would account for why I've never seen a franked joint.
Also it'd be a machined joint, difficult and pointless by hand and with a weak tenon - which wouldn't matter with a "fast" light of course
W.B. McKay 1953 makes brief mention of franking with an incredibly complicated glazing bar crossover joint.
In all of them it's referred to as an unusual joint different from a normal haunched M&T
Old joinery itself is the ultimate source of information as books tend to be of their time, or a few decades preceding.
 
What is that thing at the back of the shop? Maybe thats the game changer?
Looks to be a tenoner.
Basicalllllly very similar to a spindle moulder with a decent coping sled/sliding carriage type arrangement, permanently set up for tenons.
From memory most have two heads so you can cut top and bottom at the same time.. without having to fiddle with packers to space the middle out.
Although I’ve never seen one in the flesh I believe you could also get double ended ones, which would allow you to cut both ends of a rail at the same time.
A lot of people pie them off in favour of a spindle now.
 
What is that thing at the back of the shop? Maybe thats the game changer?
It's a single end tenoner. Funnily enough, even though I can't remember the manufacturer's name, I've recently used the same model for tenoning scaled down window frames in a teaching situation. Some of the apprentices picked up on how to set up and use the machine quicker than others. Slainte.
 
It's a single end tenoner. Funnily enough, even though I can't remember the manufacturer's name, I've recently used the same model for tenoning scaled down window frames in a teaching situation. Some of the apprentices picked up on how to set up and use the machine quicker than others. Slainte.
Presumably the work piece is set to stops rather than using marks as per the bench joinery hand tool way?
How much marking up on the workpiece would you have to do if you were making e.g. a window frame with glazing bars?
 
I think that a lot of this discussion goes to show that you shouldn't believe everything you read in books. :unsure:
 
I think that a lot of this discussion goes to show that you shouldn't believe everything you read in books. :unsure:
🤣
Just reading "Notes on Building Construction" 1899 - "New edition, Revised"
"Franking" gets a mention but only about the glazing bar crossover joint. It's not clear what part of it is the actual franking but have to say it's much the same as I do, though the simplest variant. I've been a bit of a franker all along!
It talks about "superior" work and "very good" work where a dowel is inserted joining the stub tenons at the cross over, which I've seen but never tried to copy. A bit OTT IMHO.
I'd class my work, and in fact most of the other old stuff I've looked at over the years as "just about good enough" work!
PS forgot to say - sometime in the 124 years since the book was printed somebody else was looking up the topic and the word "franking" and the accompanying drawing are both highlighted in pencil! Probably having an argument with somebody. :unsure:
 
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🤣
Just reading "Notes on Building Construction" 1899 - "New edition, Revised"
"Franking" gets a mention but only about the glazing bar crossover joint. It's not clear what part of it is the actual franking but have to say it's much the same as I do, though the simplest variant. I've been a bit of a franker all along!
It talks about "superior" work and "very good" work where a dowel is inserted joining the stub tenons at the cross over, which I've seen but never tried to copy. A bit OTT IMHO.
I'd class my work, and in fact most of the old stuff I've looked at over the years as "just good enough" work!
I think it prudent at times to look into the background of some authors. Paul H Hasluck, for example seems to fit the profile more of a journalist and editor than a skilled tradesman. Judging by the sheer variety of technical subjects he wrote about he couldn't possibly have had hands on experience in all of them.

I have to hand it to him though. the guy was prolific. From Gas fitting and Carpentry to Leatherwork and Beekeeping. :giggle:
 
Interesting thread! I had to make a house full (mine) of sash windows, and not having a morticer, tenoner, or the inclination to accurately cut 64 haunched tenons joints by hand (in Accoya which as you know is quite brittle).....I used a Domino which 5 years on is so far looking perfectly good....I'll get my coat :D
 
I think it prudent at times to look into the background of some authors. Paul H Hasluck, for example seems to fit the profile more of a journalist and editor than a skilled tradesman. Judging by the sheer variety of technical subjects he wrote about he couldn't possibly have had hands on experience in all of them.

I have to hand it to him though. the guy was prolific. From Gas fitting and Carpentry to Leatherwork and Beekeeping. :giggle:
I guess they all rework earlier writings, they'd have to, from the first - Nicholson being a rewrite of Moxon, with amendments, and so on.
Greenhalgh/Corkhill/Lowsley has sections written by about 10 different authors including familiar names like Charles Hayward. Greenhalgh is just "editor".
"Notes on Building Construction" 1899 has an intro describing additions and amendments and a long list of sources. It's "arranged to meet the syllabus of the Science& Art Department of the Committee of Council on Education South Kensington"
W B McKay comments on changes and new developments, from edition to edition. He also talks at length about Building Science syllabuses and was teacher and examiner.
They are all for training for the trade and excellent, nothing like the pop modern books at all.
 
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Interesting thread! I had to make a house full (mine) of sash windows, and not having a morticer, tenoner, or the inclination to accurately cut 64 haunched tenons joints by hand (in Accoya which as you know is quite brittle).....I used a Domino which 5 years on is so far looking perfectly good....I'll get my coat :D
I'd keep it to yourself if I were you, they are very touchy around here! 🤣
 
Presumably the work piece is set to stops rather than using marks as per the bench joinery hand tool way?
How much marking up on the workpiece would you have to do if you were making e.g. a window frame with glazing bars?
I've remembered that the machine was a Sedgewick. As to cutting the joints, it's basically a case of cutting all parts of the same profile to length on a radial arm saw, chop saw, or similar: for example cut the top and bottom rails of a light (sash) to the same required length. Then have one or two joints on a spare piece, ideally, marked out, followed by setting the machine to cut the tenon precisely to thickness, at the right distance in from both faces, and to the shoulder line(s) controlled by a depth stop. [Note. Long and short shouldered tenons can be done by moving one head horizontally.] A third head, which I never used on that machine as the cutters weren't available could be set to cut scribed shoulders. Anyway, once set up with a piece of scrap at the back of each part being tenoned to prevent spelch or break out it was just a case of push the piece up to the stop, lock in place and run the cut, flip the rail around horizontally 180º, and repeat. Best overall I think is to do the joinery first then do the mouldings, e.g., ovolo, rebate, that sort of thing as that reduces the amount of creativity needed to make up bits of backer material to reduce or eliminate break out. However, it can be a good idea to include the mouldings in the spare piece used to set up the tenoner. That way you've got a sample that can be used to ensure the actual parts have profiles that match the sample. Slainte.
 
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Best overall I think is to do the joinery first then do the mouldings, e.g., ovolo, rebate, that sort of thing as that reduces the amount of creativity needed to make up bits of backer material to reduce or eliminate break out. Slainte.
I spent some time the other day trying to make an inverse-ovolo moulding piece so I could clamp it to my right jamb so as not to wreck the joint with breakout. Notes made!
 
Had a quick dip in my scrap box and found a sash stile to bottom rail joint. Seems to be franked. Can't see much of the moulding under the paint. Knocked out the peg which may have been draw bored as it has the characteristic kink, but on the other hand it came out very easily.

IMG_5427.JPG


Started tapping it apart and low and behold a perfect "quirked astragal and hollow" moulding shows itself immediately. Obviously a machined scribe, not hand done.

IMG_5426.JPG



IMG_5429.JPG


IMG_5430.JPG



I think this is what M&T "franking" is about, namely a machine joint, and morticing out a reverse haunch is simply a bit easier than the hand tool way, if you are machining anyway.
But not necessarily a good joint and there's all sorts of messy details here, such as mortice being narrower than the flat and leaving little thin bits etc.
Just a "good enough" joint
OTOH the "franked" glazing bar crossover is quite different - a superior joint and too good for purpose?
 
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That scribe would likely have been done with a sash scribing plane. Looks far too old for machining.
 
That scribe would likely have been done with a sash scribing plane. Looks far too old for machining.
But why would you bother?
Do moulding planes come as pairs with the reverse profile? Have you seen or used one? It's across the grain which wouldn't help.
Much easier and a better joint to do the more common square shoulder plus normal haunch and just scribe or mitre the mouldings where they meet
 
I spent some time the other day trying to make an inverse-ovolo moulding piece so I could clamp it to my right jamb so as not to wreck the joint with breakout.
Work the joints as far as you can in the square, then apply mouldings and rebates.

Snapshot of how I did this simple joint in my previous post, the tenon and mould have been applied, prepping to cut a 45 on the moulding to then on to cope/frank with chisel/s


scribe 1.jpgscribe 2.jpgscribe 3.jpg

I've remembered that the machine was a Sedgewick
(y) Single ended, three head tenoner, scribe head at the far end in this case:

tenoner1.jpg


This is a joint that I may have posted before, but on scale it a bigun:

window.jpg

One I will be starting on in week or two.
 
But why would you bother?
Do moulding planes come as pairs with the reverse profile? Have you seen or used one? It's across the grain which wouldn't help.
Much easier and a better joint to do the more common square shoulder plus normal haunch and just scribe or mitre the mouldings where they meet
Yes, I have one and I used it on the frame of the window I’m making. Unfortunately it doesn’t quite match the ovolo planes I have, but i wanted to try it. It took seconds to cut the scribe. All I had to do was clamp a bit of scrap on to prevent breakout.

For a fiddly quirk moulding, to get it to be as close a match as your pic, I can’t think of another way to do it (except machines).

One I’ve done my practice window I will make a scribing plane that fits my ovolo planes.
 
Work the joints as far as you can in the square, then apply mouldings and rebates.

.....
Yes.
By hand tool or with band saw, TS, spindle, or combination thereof:
Mortices, and tenon cheeks, first. Then haunch. Then rebate and moulding. Then tenon shoulders last
 

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