# Info on London-style dovetails wanted



## Derek Cohen (Perth Oz) (9 May 2011)

I am looking for info on London-style dovetails - anything about their history, if they fit into any particular school of woodworking, who promotes their inclusion currently, and your opinion of them.

Further, what type of chisels do you use in making them, should you do so?

Any reference sources to London=style dovetails you can suggest?

Regards from Perth

Derek


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## Jacob (9 May 2011)

Never head of them. What are they?

PS googled and only found your own site Derek which seems to show an utterly conventional drawer DT.
I think of them as single kerf DTs in that the pinholes are cut in the same kerf, which looks nice and fine and is also quick and easy.


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## Derek Cohen (Perth Oz) (9 May 2011)

On the right side, Jacob ...







Reference: http://www.inthewoodshop.com/Furniture/ ... rawer.html

Dovetails like Alan Peters made them 

Regards from Perth

Derek


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## Jacob (9 May 2011)

Derek Cohen (Perth said:


> Dovetails like Alan Peters made them
> 
> Regards from Perth
> 
> Derek


You mean dovetails like I (and almost everybody else) makes them?






What do you want to know?


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## Derek Cohen (Perth Oz) (9 May 2011)

Hi Jacob

That is very nice work. =D> 

Have a look at my first post. 

This is how I prefer to make my drawers. Carcases get wider dovetails. The two styles of dovetails require a different approach in my experience. Wide tails are not difficult to chisel out as there is room to wiggle a small chisel into the corners of the slope. On the narrow tails, which can be as little as 1/8" wide, this is not possible. I favour chisels which are ground so that the shoulders are minimal. I know others do the same. 

Aussies tend to follow the British school of woodworking. Over on the US side of the Pond drawer sides tend to be a lot thicker than we tend to use, and the dovetails tend to be chunkier as a rule, so it seems. 

So I am curious what the history is on "London dovetails" (as I have come to know them), and how they are made in the traditional manner.

Regards from Perth

Derek


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## Modernist (9 May 2011)

A few points Derek

I don't understand how you get 3mm tails?

Does the London pattern refer to the wide tails or single saw cut between them. From videos I've seen they were cut as a set much like you are sawing a pair on your blog, they would cut a whole set at a time.

You drawer sides do not look too thin. I suppose it depends on the timber but trad work in oak or similar might be 1/4"on fine work.


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## Derek Cohen (Perth Oz) (9 May 2011)

> I don't understand how you get 3mm tails?



Hi Brian

It depends on the ratio that is used - 1:8 will create a skinny dovetail. I generally use 1:7

The dovetail on Jacob's drawer looks about 1:6

Regards from Perth

Derek


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## János (9 May 2011)

Hello,

I know these as "needle pin dovetails". Here, in my country, and in the continental European tradition, these narrow pins are seldom used, mostly on jewellery boxes, and secretaire desks, and other highly decorative or ornate items. They are made in exactly the same way as wider ones, but the marking out is trickier. So this is a case for "pins first" work order....

Have a nice day,

János


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## Jacob (9 May 2011)

Modernist":m1vzd84w said:


> A few points Derek
> 
> I don't understand how you get 3mm tails?......


Derek means 3mm pin holes (or pins). It's easier to think in terms of pins and pinholes.
I've looked at quite a few

starting with the pin holes;
1 all marked with a deep incised or cut shoulder line (easier to trim the shoulders straight from a cut line)
2 all cut in a single kerf (one cut on one side, then the other starting in the same kerf - keeps them neat,
3 all done freehand (you can tell from the slightly varying angles and spaces between), 
4 all over cut - usually a lot on the outside of the drawer and just a nick on the inside (makes it easy to take out the corners as you have already sawn them out)
5 not done in a batch as so often shown (very difficult to align them and then to do the sloping over cut as a second pass)

then the pins:
1 shoulder marked same as above
2 marked from the pin holes
3 overcut very slightly if at all
4 undercut in the shoulder so to be tight at the visible join

gradients very variable from 1/14 to 1/2 (in different pieces, not the same one!)

PS just seen János's post. Pinholes first for me! Same design pretty universal for drawer sides in UK. Finer work: finer gradient.


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## flounder (9 May 2011)

Jacob, what do you use to mark the pins with through the pin holes? I always struggle to find a method that fits in cleanly when the hole is so small?


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## Jacob (9 May 2011)

flounder":1t3jw5pg said:


> Jacob, what do you use to mark the pins with through the pin holes? I always struggle to find a method that fits in cleanly when the hole is so small?


X-acto type craft knife with a square end chisel blade. Single bevel. I made my own from a bit of old saw blade. As long as it is same as or thinner than your DT blade. Poke it down the pinhole and give it a light tap. Also handy as a chisel for cleaning the sides and into the corners.


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## Henry Disston (9 May 2011)

Jacob":39w1jcok said:


> X-acto type craft knife with a square end chisel blade. Single bevel. *I made my own from a bit of old saw blade*. As long as it is same as or thinner than your DT blade. Poke it down the pinhole and give it a light tap. Also handy as a chisel for cleaning the sides and into the corners.


 :shock: I just buy the #18 blades. Glad to see someone else using an Xacto knife.


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## yetloh (9 May 2011)

Derek Cohen (Perth said:


> On the right side, Jacob ...
> 
> 
> 
> ...




Derek,

Interesting that you have made them wider at the back. I tend to use the same (narrow pin) arrangement at front and back. Also, I use a scalpel for all marking out, unless it is guaged, of course. After a scalpel, I find all marking knives feel clumsy including the Blue Spruce model I acquired recently for very little - beautiful but still clumsy. Must get round to putting it on ebay.

Jim


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## Jacob (10 May 2011)

yetloh":1zui0mkh said:


> ....Interesting that you have made them wider at the back.


Again - that is how they are (nearly) all done traditionally, so it must be right. The blind DT at the front of the drawer relies on glue and close fit to keep it together. The through DT at the back is much easier to make but has much less glue area (the back is also thinner than the front) and so relies more on the strength of the pins to keep it together.


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## János (10 May 2011)

Hello,

Perhaps Jacob is right about the difference in the front and back layout. But in a drawer, most of the load is on the front dovetails, so the narrow ones would held things together equally well. There is a more practical answer for the difference; the back dovetails are seldom seen in use, as you rarely remove the drawers fully. So do not worth the effort to make them "cute". A scratch awl was the traditional way to mark out the pins (in my country), as the narrow and slender tool is capable to reach into very tight places. Cranked ones can be used on lapped dovetails too.

Have a nice day,

János


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## Derek Cohen (Perth Oz) (10 May 2011)

> Derek,
> 
> Interesting that you have made them wider at the back. I tend to use the same (narrow pin) arrangement at front and back. Also, I use a scalpel for all marking out, unless it is guaged, of course. After a scalpel, I find all marking knives feel clumsy including the Blue Spruce model I acquired recently for very little - beautiful but still clumsy. Must get round to putting it on ebay.



Hi Jim

For really slim tail-to-pin boards I use the saw blade for marking out. For this it is best to do so _before_ you remove any waste.






I am surprised at your comment about the Blue Spruce marking knife - not that I have even handled one. By reputation it has a slim blade. Generally I can get one of my own marking knives into the kerf of a standard dovetail saw, but the thinner bladed versions are a bit trickier.






These are soon to be manufactured by Chris Vesper.



> Perhaps Jacob is right about the difference in the front and back layout. But in a drawer, most of the load is on the front dovetails, so the narrow ones would held things together equally well. There is a more practical answer for the difference; the back dovetails are seldom seen in use, as you rarely remove the drawers fully. So do not worth the effort to make them "cute".



János, spot on. 

Regards from Perth

Derek


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## Jacob (10 May 2011)

Derek Cohen (Perth said:


> ....
> 
> Hi Jim
> 
> For really slim tail-to-pin boards I use the saw blade for marking out. For this it is best to do so _before_ you remove any waste.


Surely that puts your mark on the wrong side of the line?
I don't rate a knife in these circs. It's too easy to go off the line, as you can't really see it at the bottom of the pin hole. Also it's easy to slice off a bit of the side by mistake. I find the Xacto type chisel much more reliable


> > Perhaps Jacob is right about the difference in the front and back layout. But in a drawer, most of the load is on the front dovetails, so the narrow ones would held things together equally well. There is a more practical answer for the difference; the back dovetails are seldom seen in use, as you rarely remove the drawers fully. So do not worth the effort to make them "cute".
> 
> 
> 
> ...


It'd be very tiny if you did a single kerf pinhole for pins on a thin end-board less than half the thickness of the drawer front. It's for strength. You could make them "cute" if you wanted but they'd still have to be beefed up a bit.


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## Dombey (12 May 2011)

London Stylee!
OK I'm very new here and saw your Dovetail question... I have only ever come accross 3 basically traditional dovetail types... as follows "open" as used on drawer backs, "stopped" or "closed" as drawer fronts and the most difficult "secret or Mitred" as used on Bureau tops so as to look like a mitre but very difficult to do unless you know how to use a dovetail saw.... I never use a template as they were always done to eye hence always odd sized... OK so theres my first contribution for what its worth! I suppose being a traditional cabinet maker I could be wrong though sure I will be corrected?

Two Dovetails are always stronger than one..... you have enough width and will look far neater.. !

Dombey...


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## Jacob (13 May 2011)

Dombey":1yxjkv7f said:


> .... ...
> Two Dovetails are always stronger than one..... you have enough width and will look far neater.. !
> 
> Dombey...


Dunno what about this one all on it's own:






On a very old and heavy piece of french furniture. "Sans culotte" style perhaps?


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## mtr1 (13 May 2011)

Looks like a rural piece, and the tradesman was cutting down on time. The iron nail is a nice touch, looks horrible overall but functional. Doesn't look that old to me either.


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## Jacob (13 May 2011)

mtr1":2417s3f3 said:


> Looks like a rural piece, and the tradesman was cutting down on time. The iron nail is a nice touch, looks horrible overall but functional. Doesn't look that old to me either.


Was old. Well 150 years at least I'd guess. Possibly a lot older. The back boards were rip sawn by hand - looked like they'd been scratched by bears. Everything hand done, no sign of machine marks anywhere. Adze type marks , more likely a heavy cambered plane, on fronts of back boards. Fronts of front boards still showing hand plane marks from fine cambered plane done in very neat parallel passes, just visible in the right light. The most modern thing about it was the nails!
I wouldn't say it looked "horrible" at all. I really admire this sort of practical woodwork. Nothing "rural" about it either - "country furniture" is a bit of a myth; you'd find the same sort of stuff made in towns, but in the backwoods things get left behind and change is slower.


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## mtr1 (13 May 2011)

Just a taste thing, looks horrible to me(the dovetail).



Jacob":3fitvls8 said:


> Was old. Well 150 years at least I'd guess. Possibly a lot older. The back boards were rip sawn by hand - looked like they'd been scratched by bears. Everything hand done, no sign of machine marks anywhere. Adze type marks , more likely a heavy cambered plane, on fronts of back boards. Fronts of front boards still showing hand plane marks from fine cambered plane done in very neat parallel passes, just visible in the right light. The most modern thing about it was the nails!
> I wouldn't say it looked "horrible" at all. I really admire this sort of practical woodwork. Nothing "rural" about it either - "country furniture" is a bit of a myth; you'd find the same sort of stuff made in towns, but in the backwoods things get left behind and change is slower.



The drawer doesn't look like its had much use imho, and the fact that its hand made despite its late age points to a rural piece. In the backwoods things get left behind and change is slower after all. French rural pieces tend to be a bit more rustic(look older) than an English piece which is probably what threw you.


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## Jacob (13 May 2011)

I did actually see this piece, inside and out. You didn't. I'm not thrown at all!


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## Benchwayze (13 May 2011)

In carcasses, I like to see asymmetrical dovetails, a'la Krenov. For drawers I like Jacob's layout, but there's nothing wrong with having a large dovetail in the middle, or say between every other smaller tail. More gluing area I would say! 

Just to be different though I think 'London dovetails' were what some folk call 'proud' dovetails, as found in some Arts and Crafts work, but I could be wrong. 8) 

As for two dovetails v one, my old mentor said one dovetail was strongest. More side grain for gluing, but it just didn't look so nice. He could have been wrong too! :wink:

(FWIW!)

John


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## Racers (13 May 2011)

Hi,

Well the amount wood between *London* dovetails is so little you can probbaly ignore it, so it's just one big one.


Pete


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## János (13 May 2011)

Hello,

Strength of dovetails was researched in the XXth century systematically. The strength of a dovetail joint depends mostly on the angle of the tails and pins. An angle between 14 and 18 deg gives the most strength… For sliding dovetails an angle of 20~22 gives the most strength. No coincidence that most machine cut (routed) dovetails were/are made with 14 degree pins and tails… So Jacob’s higher angles would result in stronger joints.

There are methods to determine the strongest possible layout for carcass dovetails, but the resulting pattern is not too nice, resembling the machine cut joints, as the resulting pins are quite wide, nearly as wide as the tails.

But for practical purposes, like craft work, the difference does not count. Almost any arrangement would provide adequate strength for use in furniture. I seldom use dovetail pins narrower than 5mm at the base, and do make them with an approximately 1/9 slope. In very soft woods I change the slope to 1/6.






On traditional Japanese furniture, the drawers were made wit rabbets and rice paste as an adhesive, plus a few nails. This very crude construction was used even on high class pieces. And they held up quite well.

Bye,

János


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## Jacob (13 May 2011)

János":14y8or7r said:


> ....The strength of a dovetail joint depends mostly on the angle of the tails and pins. An angle between 14 and 18 deg gives the most strength…


Depends on the glue of course, or a zero angle box joint would not work. And on the size of the pins. Thin pins could snap off


> There are methods to determine the strongest possible layout for carcass dovetails, but the resulting pattern is not too nice, resembling the machine cut joints, as the resulting pins are quite wide, nearly as wide as the tails.


As is done for max strength on ammo boxes, water tanks etc. Pins and tails about the same size


> But for practical purposes, like craft work, the difference does not count. Almost any arrangement would provide adequate strength for use in furniture. I seldom use dovetail pins narrower than 5mm at the base, and do make them with an approximately 1/9 slope. In very soft woods I change the slope to 1/6.


I quite like steeper angle and single kerfs making little triangles, just for the visual effect


> On traditional Japanese furniture, the drawers were made wit rabbets and rice paste as an adhesive, plus a few nails. This very crude construction was used even on high class pieces. And they held up quite well.
> 
> Bye,
> 
> János


The Welsh used nails too, in this example at least (about 90years old) 
The bottom is set in between the sides and everything nailed, including the false front.


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## Benchwayze (13 May 2011)

I would say that the strength gained from slope of the dovetail, is only relevant when force is applied against the slope itself. (As in the front of a drawer, when the drawer is being opened) 

If you apply force to the side of a dovetailed joint, it probably has little more strength than a finger joint. 

Agree? :wink: 

John


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## János (13 May 2011)

Hello,

One must select the joinery used in accordance with the type of load. Dovetails were developed to withstand pulling loads and racking, in an age of unreliable adhesives. Dovetails are joints based on mechanical interlock, and would hold without any adhesive. The adhesive put into a dovetail simply locks the joint, and provides some strength against racking, but has no real effect on the pull strength. Perhaps the actual cross section of pins matters more than the width of individual pins, so a few wide pins would held as well as more numerous narrow ones. On some ancient pieces you can see dovetails fixed with wooden pegs... Widely available reliable animal protein adhesives were a development of the XVIIth century...

Have a nice day,

János


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## Jacob (13 May 2011)

János":19sdsyfr said:


> ...... Widely available reliable animal protein adhesives were a development of the XVIIth century...


Hmm. Invention of fire about 800000 years ago. Cooking of animals followed. I'd be very surprised if bone and hide glue were not extremely ancient. Resins even older?


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## yetloh (15 May 2011)

Think you are right there, Jacob. It is believed that the Egyptians used animal glues and there is evidence that the Sumerians used it even earlier, so hardly an invention of the 17th C.

Jim


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## János (16 May 2011)

Hello,



> Widely available reliable animal protein adhesives were a development of the XVIIth century...


And the accent was on _WIDELY AVAILABLE RELIABLE_.

Hot hide glue as a reliable commercial product was a development of the XVIIth century in Europe. And this development served as the base of the "veneered furniture revolution"... Before that marquetry and veneering was a rarity on European furniture.

The production of high and consistent quality animal protein glue is a demanding task, even today, in the age of automated processes, and was much more difficult in the past...

Not too hard to find texts about the development and history of hot hide glue in conservation/museology resources....

Have a nice day,

János


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