# why are they called dividers?



## Jacob (16 Mar 2012)

I was wondering about this when Brian was talking about how to mark up a virgin saw blade with say 14 tpi.
It came to me in the night, under the influence of Martson's Pedigree :shock: :
If you had thin batten alongside the blade marked in 14ths of an inch it'd be easy to line up and start the cut with a file.
But how would you divide  the batten into 14ths? 
Dividers?
But setting them at 1/14" and pricking out each mark looks incredibly fiddly. Even more so if you were aiming at 20tpi
SO
what about first setting them at say 1" and pricking out 1" marks. Or just doing 1" marks from a ruler.
THEN
set them at 15/14" and then marking from each of the first marks, then repeating this from the second ones, adding 1/14" each time?
It works I've just tried it on a piece of paper.
So is that why are they called dividers? For this, and similar tricks?
Maybe everybody knew this already except me, wouldn't be the first time.


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## bugbear (16 Mar 2012)

NB: Laser printed template much more practical.

BugBear


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## Jacob (16 Mar 2012)

If you compare a laser printer side by side with a pair of dividers, you will find that the dividers are simpler in many ways, not least in the number of components. 
What is more you could make up a pair from any old scrap, which would not be at all easy for a laser printer.


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## RogerP (16 Mar 2012)

Hand Saw Teeth Templates


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## Cheshirechappie (16 Mar 2012)

bugbear":1op6qggo said:


> NB: Laser printed template much more practical.
> 
> BugBear



A pair of dividers, however, does not require a 240V power supply or batteries. They don't need a computer to drive them, either; and they last longer - I have two pairs inherited from my grandfather, and they still work very effectively.

I stand to be corrected, but I have a vague suspicion that the invention of dividers preceded the invention of the laser printer by several hundred years. Indeed, dividers may have been one of the tools used by those inventing the laser printer.

Joking aside - perhaps we've come to rely too much on steel rules and tapes. A study of older books on geometry indicates many ways in which lengths can be divided up without any measuring. It's possible that many 17th and 18th century craftsmen did not have the numercy to do the mental arithmetic required to divide up by using a ruler to mark out dovetails and such jobs, but could use dividers perfectly adequately. (They could probably reckon up their wages well enough, though....)


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## AndyT (16 Mar 2012)

Jacob - if you don't follow it already, I recommend you have a look at Peter Follansbee's blog - you could start with this entry: http://pfollansbee.wordpress.com/2010/12/06/a-paire-of-compasses/

He works on 17th century joiner's furniture as a historical re-enactor and is keen on discovering past methods through practical work. I think you would also enjoy his very practical approach to work which is quick and suitable for its purpose, and his close examination of old furniture. (That said, in this particular post, he is also looking back at written evidence.)


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## Jacob (16 Mar 2012)

AndyT":2khnadh4 said:


> Jacob - if you don't follow it already, I recommend you have a look at Peter Follansbee's blog - you could start with this entry: http://pfollansbee.wordpress.com/2010/12/06/a-paire-of-compasses/
> 
> He works on 17th century joiner's furniture as a historical re-enactor and is keen on discovering past methods through practical work. I think you would also enjoy his very practical approach to work which is quick and suitable for its purpose, and his close examination of old furniture. (That said, in this particular post, he is also looking back at written evidence.)


Thanks, very interesting. 
He doesn't mention dividers or the dividing process though. Schwarzy does on p146 of ATC, which I admit to not entirely understanding on first reading, but I do now.
I think I've been missing out on dividers. Over the years I've divided hundreds of windows into equal sized panes, but basically by maths (on the rod)


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## Cheshirechappie (16 Mar 2012)

Here's another way of using them.

Suppose you've got a workpiece you want to divide up equally, perhaps for setting out dovetails, but it's an awkward width. Take a ruler, and set it across the board, but not at right angles, at an angle that brings an easily-divided dimesion at one side. At this point, you'll have a triangle - the length you're trying to divide, an easily-divided length on the ruler making the hypotenuse, and the short side (length immaterial) making the third side of the right-angled triangle. Mark with a pencil from the ruler, and project with a try-square perpendicular to the side you want divided. Set your dividers to this length, and you can step off the divisions on all four sides of a carcase or box.


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## Jacob (16 Mar 2012)

Cheshirechappie":4fiielie said:


> Here's another way of using them.
> 
> Suppose you've got a workpiece you want to divide up equally, perhaps for setting out dovetails, but it's an awkward width. Take a ruler, and set it across the board, but not at right angles, at an angle that brings an easily-divided dimesion at one side. At this point, you'll have a triangle - the length you're trying to divide, an easily-divided length on the ruler making the hypotenuse, and the short side (length immaterial) making the third side of the right-angled triangle. Mark with a pencil from the ruler, and project with a try-square perpendicular to the side you want divided. Set your dividers to this length, and you can step off the divisions on all four sides of a carcase or box.


I like it! 
There must be lots of ways of using dividers. I'm a bit irked with myself - I've been going on for years about the rod being a non numeric graphic calculator etc. etc. but I haven't got any dividers! Ebay here I come!

PS Ed is describing same process over here http://woodworkuk.com/


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## RogerP (16 Mar 2012)

I've one of these point to point thingies. Very handy at times


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## matthewwh (16 Mar 2012)

Outstanding!

The one tool that I would have considered more Jacobish than any other in existance!

Try taking the radius of a circle and then walking that dimension around the circumferance - perfectly divided by six. Now use the dividers to describe an arc from each point between the lines both inside and outside the original circle and join them with a line eminating from the centre. By repeating this process you can theoretically divide a circle into individual degrees.

I have a feeling this may transpire into a thread of cool recipes for divider magic and I hope it will.


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## jimi43 (16 Mar 2012)

I would answer this but I've been taught to be cautious!

:mrgreen: 

Jim


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## Vann (17 Mar 2012)

Cheshirechappie":119uea0b said:


> Suppose you've got a workpiece you want to divide up equally, perhaps for setting out dovetails, but it's an awkward width. Take a ruler, and set it across the board, but not at right angles, at an angle that brings an easily-divided dimesion at one side. At this point, you'll have a triangle - the length you're trying to divide, an easily-divided length on the ruler making the hypotenuse, and the short side (length immaterial) making the third side of the right-angled triangle. Mark with a pencil from the ruler, and project with a try-square perpendicular to the side you want divided. Set your dividers to this length, and you can step off the divisions on all four sides of a carcase or box.


That's how I was taught during my apprenticeship (many moons ago ! ) - that's assuming what you're trying to say, and what I think you're saying, are the same :mrgreen: 

Cheers, Vann.


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## GazPal (17 Mar 2012)

Vann":2prflv82 said:


> Cheshirechappie":2prflv82 said:
> 
> 
> > Suppose you've got a workpiece you want to divide up equally, perhaps for setting out dovetails, but it's an awkward width. Take a ruler, and set it across the board, but not at right angles, at an angle that brings an easily-divided dimesion at one side. At this point, you'll have a triangle - the length you're trying to divide, an easily-divided length on the ruler making the hypotenuse, and the short side (length immaterial) making the third side of the right-angled triangle. Mark with a pencil from the ruler, and project with a try-square perpendicular to the side you want divided. Set your dividers to this length, and you can step off the divisions on all four sides of a carcase or box.
> ...



But then we're moving into territory involving the use of squares, tangents and sliding bevel  

Incidentally, dividers/compass are ideal tools for pattern making when producing bull-nose/lancet/flat arches, elipse, etc., as well as comparatively straight forward divisions of spans and proportional work.


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## Harbo (17 Mar 2012)

They were always standard issue in Drawing Instrument sets.

Funnily Wiki calls them Caliper Dividers?

Rod


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## Alf (17 Mar 2012)

Jacob":2v4ja7mt said:


> I'm a bit irked with myself - I've been going on for years about the rod being a non numeric graphic calculator etc. etc. but I haven't got any dividers!


You might like the Sector too, Jacob. Pop Wood did an article on using one not long ago; should think a Google will drag some info.


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## Jacob (17 Mar 2012)

Alf":3itqdr8q said:


> Jacob":3itqdr8q said:
> 
> 
> > I'm a bit irked with myself - I've been going on for years about the rod being a non numeric graphic calculator etc. etc. but I haven't got any dividers!
> ...


These things? Sort of angular slide rule. I use an ordinary slide rule occasionally.
The Gunther scale further down has parallel lines and angled lines crossing (diagonal scales) - which is where you'd set your dividers to the chosen measure plus fractions, depending on what the scale is designed to do. I bet a saw maker/doctor would have a similar purpose made scale for taking off tpi measurements.


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## Harbo (17 Mar 2012)

I have a load of them somewhere that I inherited from my Grandfather - he was a Mechanical Engineer and worked at Kitsons & Co. Leeds who designed and made Locos in the early 1900's.

Never fathomed them out though?

Rod


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## Alf (17 Mar 2012)

The PWW article simplified the use somewhat, for us poor woodworkers. Hang on, there was a video if I recall correctly... Here 'tis. Wouldn't say it was the be-all and end-all of knowledge on the matter, but it gives the gist.


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## DrPhill (17 Mar 2012)

Can you use a triangle and straight edge to create parallel lines? If so, then this is how we were taught to divide a line A-B into n equal parts.

Draw a line starting A at an angle to AB, say 45 degrees, but it does not matter really. The mark of n equal units (any size, but approximately the right size is best. the last mark is point C Now draw line BC. Set up your triangle and rule to draw parallels to BC. Draw a parallel through each of the marks on AC so that the line intersects AB. You have just divided AB into n parts with no measuring.

This is almost the same as the method suggested above by CheshireChappie, except that you do not need to choose the length of AC. It can be completely arbitrary. 

I find that sort of technique much more pleasing.....


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## Cheshirechappie (17 Mar 2012)

So far as using triangles to divide a line, I certainly don't claim any originality - I learned it in Engineering Drawing lessons at school, and the method probably predates the invention of the ruler!

I do like the Sector though - wonderfully simple. I might just have to make one of those. Thanks, Alf!

There are a couple of old engineering tricks for adjusting firm-joint dividers, which tend to be a bit 'jerky' to adjust by hand pressure on their legs. If you want to close them up a smidgen, hold by one leg and knock the other on the edge of the bench - you get to know how hard to knock your particular pair, but it's usually a harder knock than you might think. If you want to open them up a gnat's, turn them upside down, hold by one leg, and knock the joint on the bench top. Again, how hard depends on the particular joint firmness of your pair. Fitters and turners used to adjust their dividers and callipers to a nicety by this method - adjusting by the odd 'thou' was quite easy with a bit of practice - we don't need that level of precision!

For woodworking, the engineer's type dividers with the slender legs can be quite flexible once they get bigger than about 4" or so. I prefer the older-type chunky ones, often fitted with a wing and lock. If the joint is as firm as it should be, the wing lock isn't really needed, but it is an extra insurance against knocks when it's lying in the bench tool-tray. Axminster do a good new one - bought it off them a couple of months ago, and was impressed. It comes with a pencil holder and a (rather useless) carbide scriber with a plastic stem, but the basic divider is solid and well-made. It's a woodwork only tool, though - the points are not hard enough to last when marking metals. Against that, the modern engineer's sort are hard enough to mark metals happily if you need to, and most new ones have a fine screw adjustment which some people prefer to the knocking method. They all work fine if you use them with suitable care and regard for their limitations.


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## DrPhill (17 Mar 2012)

Cheshirechappie":241g5x2p said:


> So far as using triangles to divide a line, I certainly don't claim any originality - I learned it in Engineering Drawing lessons at school, and the method probably predates the invention of the ruler!
> 
> I do like the Sector though - wonderfully simple. I might just have to make one of those. Thanks, Alf!



So did I, though it was called 'Technical Drawing', and seemed so obvious that it made me an easy 'O' level. We do seem to be a bit dependent on high tech these days when simple works just as well. But I love the 'simple'. Just like that sector. I had not seen one before, but now I will make one the very next need. Thanks.


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## David C (18 Mar 2012)

I much prefer the divider method for laying out dovetails.

This appears to come from the Barnsley workshop and I learned it from Rob Cosman.

It takes a while to describe but is very quick and simple once you get it.

Described in my third book page 118, it seems a lot less cumbersome than the ruler and parallel lines method. It gives you the position of the sawcuts rather than the centre of the tails.

best wishes,
David Charlesworth


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## Jacob (18 Mar 2012)

Are you going to tell us what it is or do we have to buy the ******* book? :lol: :lol:


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## David C (18 Mar 2012)

I'm afraid it took two pages and diagrams to explain, so not doing it here.

Library?

David


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## Jacob (18 Mar 2012)

Scan, post here?


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## Alf (18 Mar 2012)

Pretty clear explanation here, Jacob. Well it makes sense to me, but then I know how it works. Oh well, better than nothing anyway. Until the library opens.


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## Jacob (18 Mar 2012)

Ta Alf that's a very neat divider action! In fact same as Schwarzy describes in the ATC, which I didn't get on first reading.


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## David C (18 Mar 2012)

Thanks Alf, very good. (I don't have the technology or patience for something that long).

NB the saddle dovetail marker seems to outperform all the complex centre based templates.

How on earth did the sloped ruler method come to be in all the textbooks?

David Charlesworth


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## Cheshirechappie (18 Mar 2012)

The 'sloped ruler' method isn't in any woodworking textbook I 've read (mind you, I haven't read them all!). It's just a geometrical method of dividing a length into equal spaces without using arithmetic. The only reason for using a ruler is that it's a stick with convenient divisions on it - you could make your own with a lath and a pair of dividers.

We seem to have got a bit side-tracked into dovetails. The method can be used to equally divide a length for any reason - spacing screw-holes, say, or sawteeth when re-filing a sawplate (as Jacob's original post mentioned). You don't even need to use dividers; a pair of trammels might do for larger jobs like panel spacing, or even a second lath with pencil marks. Come to that, a piece of string with knots.

Thinking about the sawplate example, it might be best to do something like that in two stages. First, divide the whole length of the sawplate into 1" spaces, then subdivide each 1" block into number of teeth required. Stepping out over a hundred tiny divisions over a full sawplate length would be fiddly and probably subject to cumulative errors.

Like lots of practical things, a bit of thinking before starting could eliminate many a slip!


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## wcndave (18 Mar 2012)

RogerP":15t8eqz1 said:


> I've one of these point to point thingies. Very handy at times



I have one of these and binned it first day. I could open one end to 2" whilst the other was still shut.

Nothing equal bout them at all that i could see...


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## Jacob (18 Mar 2012)

David C":1jc6m2t6 said:


> Thanks Alf, very good. (I don't have the technology or patience for something that long).
> 
> NB the saddle dovetail marker seems to outperform all the complex centre based templates.
> 
> ...


Who needs a DT marker? What's wrong with a sliding bevel?


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## David C (18 Mar 2012)

If a square line is wanted, we have two operations with two tools.

Many bevels are rather large and inconvenient for small work.


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## Alf (18 Mar 2012)

A dovetail marker is a lot easier to make than a sliding bevel, I can tell you. I like 'em; puts a gloss of efficiency onto the otherwise plodding nature of my dovetailing. I get there, but it ain't fast. :lol:

Hey, using dividers to acquire a particular dovetail slope ratio. There's another one. I'm starting to think my steel rule could become utterly redundant... :-k


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## David C (18 Mar 2012)

The marker is so slick to use. I find it very odd that the use of dividers and marker could have fallen from favour.

David


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## Jacob (18 Mar 2012)

David C":3t6fafk7 said:


> The marker is so slick to use. I find it very odd that the use of dividers and marker could have fallen from favour.
> 
> David


The tradition is largely freehand. 
Easy for both layout and cutting when there are just a few, and single kerf, as on drawer sides. 
Less easy on bigger items where I guess dividers would certainly be used to pin prick positions, though the cutting itself would be freehand.
So the woodwork circus clowns who do hi-speed freehand DT demos to the sound of Foggy Mountain Breakdown are actually showing something useful for a change!


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## bugbear (19 Mar 2012)

Cheshirechappie":3vpvnnd4 said:


> The 'sloped ruler' method isn't in any woodworking textbook I 've read



I've read lots - it's quite commonly quoted in some of them,

BugBear


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## Cheshirechappie (19 Mar 2012)

bugbear":holc409y said:


> Cheshirechappie":holc409y said:
> 
> 
> > The 'sloped ruler' method isn't in any woodworking textbook I 've read
> ...



Oh the joys of selective quotes - I did point out that I hadn't read them all!


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## bugbear (19 Mar 2012)

Cheshirechappie":324rwym0 said:


> bugbear":324rwym0 said:
> 
> 
> > Cheshirechappie":324rwym0 said:
> ...



But your point stands on its own merits, and remains true!

It's just that I'm a more than avid reader of older references (books, magazines, catalogues etc).

I have by no means read them all, but I've read a lot.

BugBear


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## David C (19 Mar 2012)

BugBear,

Joyce and Wearing come to mind, suggesting that the ruler method was in vogue at Loughborough after the war.

I can't go further back than that.

Have you seen divider method mentioned please?

David


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## woodbloke (19 Mar 2012)

David C":38zdfk04 said:


> I much prefer the divider method for laying out dovetails.
> 
> best wishes,
> David Charlesworth


Very simply described, and much easer with pics it's thus, assuming the board is say 75mm and is to be split with three tails:
1. Mark the two half tails each side, all round, so that there are two lines on the end grain at each side.
2. Place one point of the divider on a line, set the dividers to roughly a third the distance and walk it twice across the end, making two dots.
3. Go to the other side of the wood with the divider on the same setting and walk it twice back the other way, so you should now end up with four dots on the wood, fairly close together, depending on how fine you want the tails to be.
4. The two pairs of dots mark the positions of the pins and from there it's easy to complete the rest of the marking out for the joint - Rob


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## David C (19 Mar 2012)

What I wonder, is Jacobs tradition, apart from unsolicited, rude and inapropriate comments?

David


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## Cheshirechappie (19 Mar 2012)

David C":1ecz234d said:


> BugBear,
> 
> Joyce and Wearing come to mind, suggesting that the ruler method was in vogue at Loughborough after the war.
> 
> ...



By 'eck, 'ees raight, tha knaws!

I've just had a look in Wearing (The Essential Woodworker, Fig 268, p. 137) and there it is! (I suppose I could be pedantic and claim that the diagram shows a stick with equal divisions, not a ruler; but that would be dancing on the head of a pin. Besides, a ruler could be said to be a stick with equal divisions on it...)

Sorry David - you're right, I'm wrong!


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## Jake (19 Mar 2012)

David C":2f4phskd said:


> What I wonder, is Jacobs tradition, apart from unsolicited, rude and inapropriate comments?



The idea of an unsolicited comment on teh internet really made me laugh. =D>


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## Jacob (19 Mar 2012)

Old Wearing an unreliable witness IMHO. You might work out your spacings on paper by the ruler and off set angle system whatever you call it but to do it on the workpiece would be very fiddly. It'd be easier to go straight for the division into fractions and certainly be easier to use dividers. 
His drawer DTs are all chunky and he's committed to the mythical 1 in 6 or 8 angles. This means he has not spent much time looking at old furniture where these things are done differently, and better IMHO. The commonest drawer DT in the real world is the single kerf going to a point. This is found almost everywhere in light furniture and is not only elegant but also easy - there is only one line to square across and this sets a kerf for the two cuts. It's seems to be ignored by writers as a whole - in deference presumably to Barnsley's own arbitrary rules.
Wearing also uses the daft detail at the back of drawers - a screw in a countersunk slot. This does not work at all well. If the bottom is likely to move it will simply pull out of the front. This proves he's out of touch IMHO.

However good the books they shouldn't be taken as gospel. More truth to be found in old woodwork itself.


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## Jacob (19 Mar 2012)

David C":21msvio3 said:


> What I wonder, is Jacobs tradition, apart from unsolicited, rude and inapropriate comments?
> 
> David


Your unsolicited, rude and inapropriate comments noted! Ina*p*propriate BTW, 3 Ps. They are devils for correct spelling on here!


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## Jake (19 Mar 2012)

Jacob":1n6kee9a said:


> David C":1n6kee9a said:
> 
> 
> > What I wonder, is Jacobs tradition, apart from unsolicited, rude and inapropriate comments?
> ...



Tsk, "are noted", surely. Pompous waggy-finger thing at you in a headmastery-way.


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## Sgian Dubh (19 Mar 2012)

David C":ayephs3d said:


> Joyce and Wearing come to mind, suggesting that the ruler method was in vogue at Loughborough after the war.
> 
> Have you seen divider method mentioned please? David


David, I've no idea if the slopey ruler method of setting out dovetail spacing was particularly a post-war Loughborough thing: I've used that method a lot when I get especially nitpicky about even spacing, but then I was taught a fair amount of my furnituremaking by Bob Wearing... perhaps some of his inflluence stuck.

I've even described the slopey ruler method in some of my own witterings on dovetailing, see below. Incidentally, if you follow the methodology described in Joyce for setting out dovetails using the slopey ruler method it's incorrect-- you'll end up with the two outside tails wider than all the rest in the set, that's if my memory serves me right because I can't be bothered to go and replicate his described method.

I've also used the divider method several times-- there's no gain in speed over the slopey ruler method that I've been able to discern, and neither method is as fast as simply eyeballing the spacing as you go, ie, eyeball half the width, eyeball half the two remaining widths, etc. Slainte.


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## Jacob (20 Mar 2012)

Sgian Dubh":wr4f2i83 said:



> .....
> I've even described the slopey ruler method in some of my own witterings on dovetailing, see below. Incidentally, if you follow the methodology described in Joyce for setting out dovetails using the slopey ruler method it's incorrect-- you'll end up with the two outside tails wider than all the rest in the set, .....


Actually the method you show is incorrect - you will end up with the two outside tails narrower than the others, unless you abandon the 2/3 the width suggestion and just have half a pin (which would also be wrong).
Joyce gets it wrong too, but differently!
Basically it's fraught with little complications, and obviously isn't traditional (if you look at old furniture). Does it account for the way that so many modern makers make the outer pins too thin and have abandoned the single kerf pin? I thought it might be fashion but no, it's Wearing and Joyce (and all their followers) getting it wrong!
If you were going to use it it'd be better done on a piece of paper or board (a mini rod) rather than on the workpiece. After all you will only have to repeat it for each side unless you have made up a little rod with which to transfer the measurements.

The divider method will at least get things equalized, but for most purposes eyeballing freehand is going to be fine. And the little random errors of freehand (if they occur) tend to look easier on the eye than the systematic regular error of a method which doesn't work.

PS Wearing's method (fig 268) acknowledges the problem of the different sized outer pin but without quite showing how to solve it i.e. centre line plus half pin width both sides, or one side on the outer pin. Not that it's difficult but it _is_ potentially confusing.


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## bugbear (20 Mar 2012)

David C":2iqndewr said:


> BugBear,
> 
> Joyce and Wearing come to mind, suggesting that the ruler method was in vogue at Loughborough after the war.
> 
> ...



It's also mentioned in "woodworking made simple", and several (St) Charles Hayward books (since Hayward reused content so much, counting them is pointless!). It's only mentioned in the larger references, none of the thinner books mention it.

Interestingly it's *not* in Kirby's "The Complete Dovetail", probably because Kirby emphasizes the design possibilities of more interesting layouts than equal spacing. It's also absent from Bernard Jones "Practical Woodworker", Hooper & Wells, and Ellis.

The divider method was mentioned, but since I wasn't looking for it, I didn't note which books it appeared in. By far the commonest method mentioned was to measure the distance and use arithmetic division.

But Holzapfel says "Very little care is taken in setting out the pins; indeed, their distances are usually marked with a pencil, without the rule or compasses, and the two external pins are always left nearly as strong again as the others."

BugBear


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## Jacob (20 Mar 2012)

bugbear":1xyxr1x2 said:


> .......... By far the commonest method mentioned was to measure the distance and use arithmetic division.


Let's face it, it is easiest and quickest, next to freehanding:-


> But Holzapfel says "Very little care is taken in setting out the pins; indeed, their distances are usually marked with a pencil, without the rule or compasses, and the two external pins are always left nearly as strong again as the others."
> 
> BugBear


Couldn't agree more! Though for some purposes where strength is paramount such as tanks and cisterns, a very regular setting out method would be better I think.

It's a pity that these threads seem so often to revolve around what is merely _written_ by various "experts". It's much more interesting and informative to look at real woodwork and to find out what real woodworkers used to do in the real world. Start now (if you have an oldish piece) - how are the DTs set out, and why?


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## Racers (20 Mar 2012)

But how do the "real woodworkers" find out what to do? they must have learnt from someone. We haven't got that someone so books/forums do have a part to play.

Why don't you wright a book Jacob?

Pete


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## Jacob (20 Mar 2012)

Racers":3j4ss843 said:


> But how do the "real woodworkers" find out what to do? they must have learnt from someone. We haven't got that someone so books/forums do have a part to play.


Books and forums yes of course. But first and foremost look at stuff and don't take anything for granted. 
IMHOif you haven't got a trade experienced person to consult then looking at stuff is the most important part of the learning process - even better if you can pull it apart and put it back together again.


> Why don't you wright a book Jacob?
> 
> Pete


Nobody'd buy it!  
Be handy though - instead of trying to answer questions I could just say "it's on page 365 of volume 12 (available from all good bookshops with free DVD)" etc. etc. :lol:


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## GazPal (20 Mar 2012)

Jacob":3r4zg3wn said:


> Racers":3r4zg3wn said:
> 
> 
> > But how do the "real woodworkers" find out what to do? they must have learnt from someone. We haven't got that someone so books/forums do have a part to play.
> ...




Free DVD? !!!!!! I'll have two copies, but be sure to sign them.  Soon to be available through Amazon at half their RRP :wink:


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## Alf (20 Mar 2012)

Go on, Jacob, dare you. I'd buy it - I think it'd be educational for all involved. But you'd have to promise not to sign it; can't abide authors scribbling all over my books. 

For what it's worth, as I had the first volume of The Woodworker out anyway (1901), I looked at its piece devoted to dovetailing last night and while it was firm on the frequency of the pins, it neglected to mention _how_ to go about laying them out. Similarly, stern words on appropriate angles (with drawing) but no word on whether you should get out the bevel or dovetail marker or Mk1 eyeball. So no earthly use at all, but for the purposes of elimination...


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## Sgian Dubh (20 Mar 2012)

Jacob":37d5tk4s said:


> Actually the method you show is incorrect - you will end up with the two outside tails narrower than the others, unless you abandon the 2/3 the width suggestion and just have half a pin (which would also be wrong).
> Joyce gets it wrong too, but differently!


Yes, off a wee bit, but hard to detect as there's usually only about 0.5- 1 mm variation between the pin centres. Joyce's method leaves the differences visually quite obvious, which was how I spotted it because I tried it a couple of times and there it was.



> Basically it's fraught with little complications...


I've never found it in the slightest complicated, so nothing fraught that I'm aware of. 



> ... and obviously isn't traditional (if you look at old furniture).


You're quite correct Jacob. It isn't traditional I suppose, and I think perhaps I could revisit ancient Egyptian dovetailing layouts for the proper form. I wouldn't want to use any of those rubbish modern dovetail types such as those from the English Walnut period say, or any of that naff Georgian stuff (sic).



> I thought it might be fashion but no, it's Wearing and Joyce (and all their followers) getting it wrong!


Wrong? Or just doesn't comply with your definition of right? 



> If you were going to use it it'd be better done on a piece of paper or board (a mini rod) rather than on the workpiece. After all you will only have to repeat it for each side unless you have made up a little rod with which to transfer the measurements.


Huh? Why mark dovetails out on paper or rods? A waste of time surely? Mark the wood as necessary and cut it is the way I've always preferred to work. 



> The divider method will at least get things equalized, but for most purposes eyeballing freehand is going to be fine. And the little random errors of freehand (if they occur) tend to look easier on the eye than the systematic regular error of a method which doesn't work.



Agreed, dividers work, freehand eyeballing works fine too, and the sloped rule method also works, even though you seem not to like it. There's usually lots of ways to achieve things, so whatever works works, and it doesn't have to be "traditional" to be right surely?



> PS Wearing's method (fig 268) acknowledges the problem of the different sized outer pin but without quite showing how to solve it i.e. centre line plus half pin width both sides, or one side on the outer pin. Not that it's difficult but it _is_ potentially confusing.


I don't think I know that drawing of Wearing's. I can't recall ever seeing a drawing or a written description created by him for setting out tails and pins. I only remember him demonstrating the method during a lesson and going from there with it. Slainte.


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## Jacob (20 Mar 2012)

Sgian Dubh":2d021bq3 said:


> ....
> Yes, off a wee bit, but hard to detect as there's usually only about 0.5- 1 mm variation between the pin centres. Joyce's method leaves the differences visually quite obvious, which was how I spotted it because I tried it a couple of times and there it was.
> 
> 
> ...


Off a wee bit? The complication is that all these systems will be off a wee bit unless you are very careful Why not eyeball to begin with?


> > ... and obviously isn't traditional (if you look at old furniture).
> 
> 
> You're quite correct Jacob. It isn't traditional I suppose, and I think perhaps I could revisit ancient Egyptian dovetailing layouts for the proper form. I wouldn't want to use any of those rubbish modern dovetail types such as those from the English Walnut period say, or any of that naff Georgian stuff (sic).
> ...


I haven't got a definition of right. I'm suggesting that traditionally they were done much more freely and more easily. Lots of variations. What _they_ get wrong is first of all in suggesting that theirs _is_ the right way, secondly in getting it wrong a wee bit, thirdly in ignoring how it's done traditionally, fourthly in making it difficult.


> > If you were going to use it it'd be better done on a piece of paper or board (a mini rod) rather than on the workpiece. After all you will only have to repeat it for each side unless you have made up a little rod with which to transfer the measurements.
> 
> 
> Huh? Why mark dovetails out on paper or rods? A waste of time surely? Mark the wood as necessary and cut it is the way I've always preferred to work.


Work it out once (for all the drawers of the same size), instead of marking up each one individually


> > The divider method will at least get things equalized, but for most purposes eyeballing freehand is going to be fine. And the little random errors of freehand (if they occur) tend to look easier on the eye than the systematic regular error of a method which doesn't work.
> 
> 
> 
> Agreed, dividers work, freehand eyeballing works fine too, and the sloped rule method also works, even though you seem not to like it. There's usually lots of ways to achieve things, so whatever works works, and it doesn't have to be "traditional" to be right surely?


Traditional _tends_ to be "right" in that it usually is the tried and tested most efficient way of doing anything.


> > PS Wearing's method (fig 268) acknowledges the problem of the different sized outer pin but without quite showing how to solve it i.e. centre line plus half pin width both sides, or one side on the outer pin. Not that it's difficult but it _is_ potentially confusing.
> 
> 
> I don't think I know that drawing of Wearing's. I can't recall ever seeing a drawing or a written description created by him for setting out tails and pins. I only remember him demonstrating the method during a lesson and going from there with it. Slainte.


In the book.
What ever happened to the single kerf DT? It's effective, easiest, most common, and is neat and tidy.


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## bugbear (20 Mar 2012)

Alf":290yop30 said:


> ..as I had the first volume of The Woodworker out anyway (1901), ...



DRIVE BY!!!

BugBear


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## Racers (20 Mar 2012)

I thought she was younger :wink: 


Pete


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## GazPal (20 Mar 2012)

Jacob":weqf8fl5 said:


> What ever happened to the single kerf DT? It's effective, easiest, most common, and is neat and tidy.



It's among the dovetail types we were taught at school and used during my apprentice years and since. I still prefer their appearance, as well as ease of execution.


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## Sgian Dubh (20 Mar 2012)

Jacob":wrxuf9w1 said:


> In the book.


Which book Jacob? Not Joyce's The Technique of Furniture Making I presume because figure 268 in my copy of that is an image of slot hinge.

I haven't got the time to respond to the rest of your points I'm afraid as I have other things I really need to attend to. Sorry. Slainte.


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## Modernist (20 Mar 2012)

GazPal":1d069v5u said:


> Jacob":1d069v5u said:
> 
> 
> > What ever happened to the single kerf DT? It's effective, easiest, most common, and is neat and tidy.
> ...



Nothing wrong with it but it is not the strongest so some limits as to use. Also it can be awkward to clean out when the mating piece is thin leaving a very narrow triangle to remove (assuming a decently shallow slope is used).

Fine therefore for the backs of pine drawers where it was regularly found with a steeper slope.


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## GazPal (20 Mar 2012)

Strength-wise I tend to err on the side of improving the partnership between increased long grain gluing surface and mechanical interaction between constituent parts. Matching a joint to an end product's purpose tends to influence type and variation, but pins don't need to be massive for the sake of structural strength and single kerf dovetails aren't necessarily a weaker variant if correctly constructed with tails and pins snugly interlocked.

It's quite surprising just how much structural stress a simple pine drawer can be put through during it's lifetime, but it's corner joints are only part of a larger equation including the attachment of front and bottom to a drawer carcase.


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## Jacob (21 Mar 2012)

Modernist":11lfnc50 said:


> ....
> Fine therefore for the backs of pine drawers where it was regularly found with a steeper slope.


Not as far as I know, from what I've seen.
DT pins at the back usually fatter double kerf; due to thinness of the back has to be beefed up and appearance not an issue. Single kerf DTs seem to be common at the front of hard and soft wood drawers. Seen everywhere in older furniture wherever hand made, apparently first choice of many makers, presumably because easiest and also quite elegant. Mainstream makers that is, not arts n crafts etc. Did A&C make them unfashionable?


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## bugbear (21 Mar 2012)

Jacob":12og8pfj said:


> Modernist":12og8pfj said:
> 
> 
> > ....
> ...



My observations (from attending many auction viewings, and looking at lots of furniture) agrees with Modernist, at least for pine.

Backs of drawers, say 5" deep, with 3-4 isoceles triangles for pins.

BugBear


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## bugbear (21 Mar 2012)

Jacob":q4nntwyz said:


> It's much more interesting and informative to look at real woodwork and to find out what real woodworkers used to do in the real world. Start now (if you have an oldish piece) - how are the DTs set out, and why?



I think what you're espousing is more generally known as archaeology, and what I've been doing in this thread is more generally known as history.

I think *both* approaches to knowledge are normally deemed useful.

BugBear


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## Jacob (21 Mar 2012)

bugbear":2bixlxx3 said:


> Jacob":2bixlxx3 said:
> 
> 
> > Modernist":2bixlxx3 said:
> ...


I just had a quick look around the house. (I know, I know. I should be doing some work - it only took minutes!)
Drawers in 9 pieces of furniture with hand made DTs (not made by me):
the back pins on 7 were trapezoid and 1 was triangular ("single kerf")
The front pins on 6 were triangular ("single kerf"), 1 was in between - probably started as single kerf but got widened. 1 was trapezoid.
The odd one out had peculiar shapes all slightly different!
Large majority conform to what I think was the most common pattern; single kerf at the front and double kerf at the back. This was true of the best (nice little davenport with mahogany 2ary timber and ebony, ebony veneer, birds eye maple as 1ary timber) and the worst (wardrobes and 2 pine chests of drawers), so quality and materials seem to have nothing to do with it - it's just best (and easiest) practice.
A triangular back pin is least likely as drawer sides usually overshoot the back in which case a triangular pin couldn't fit - a trapezoid becomes inevitable.

The arts n crafts DTs are all trapezoid, for no good reason other than fashion. Strength doesn't come into it as in ordinary furniture DTs never fail, large or small. Even that wreck of a dresser (which I worked over in another thread) which arrived in bits, had DTs still in good condition, just needing sticking back together again. Incidentally (Rob take note!) what had failed in every drawer (7) was the bottom edge of each side, due to having slots, not slips.


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## Jacob (21 Mar 2012)

bugbear":1v90w8e2 said:


> Jacob":1v90w8e2 said:
> 
> 
> > It's much more interesting and informative to look at real woodwork and to find out what real woodworkers used to do in the real world. Start now (if you have an oldish piece) - how are the DTs set out, and why?
> ...


Hmm. But there isn't much history - that's the nature of trad craft work everywhere - it's largely passed on by word and demonstration. "The Wheelwrights Shop" is very unusual. But there is plenty of archaeology.
History without archaeology might be only hearsay or myth. Troy was thought to be myth until it was excavated. But much archaeological evidence exists without any history at all, other than what can be inferred from the artifacts. Hence archaeology is tops especially when you are discussing artifacts.
So - if you want to know about woodwork, look at woodwork; there's plenty of it about. There's a bit near you, even as we speak! (It's behind you!)


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## Alf (21 Mar 2012)

bugbear":2pjsqwfp said:


> Alf":2pjsqwfp said:
> 
> 
> > ..as I had the first volume of The Woodworker out anyway (1901), ...
> ...


Oh, I wish - 'tis the reprint. They did it very nicely though.



Racers":2pjsqwfp said:


> I thought she was younger :wink:


You should see the portrait in the loft... :lol:


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## Racers (21 Mar 2012)

Doreen Gray?


Pete


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## Jacob (21 Mar 2012)

:lol: 
So it's been Doreen all along? Now we know!


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## Tony Spear (21 Mar 2012)

DrPhill":1zrc68m9 said:


> Can you use a triangle and straight edge to create parallel lines? If so, then this is how we were taught to divide a line A-B into n equal parts.
> 
> Draw a line starting A at an angle to AB, say 45 degrees, but it does not matter really. The mark of n equal units (any size, but approximately the right size is best. the last mark is point C Now draw line BC. Set up your triangle and rule to draw parallels to BC. Draw a parallel through each of the marks on AC so that the line intersects AB. You have just divided AB into n parts with no measuring.
> 
> ...



Even easier if you have a parallel rule, as I do, along with my vintage brass compasses from my Yacht Master days.


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## Modernist (21 Mar 2012)

Jacob":33jq8neu said:


> I just had a quick look around the house. (I know, I know. I should be doing some work - it only took minutes!)
> Drawers in 9 pieces of furniture with hand made DTs (not made by me):
> the back pins on 7 were trapezoid and 1 was triangular ("single kerf")
> The front pins on 6 were triangular ("single kerf"), 1 was in between - probably started as single kerf but got widened. 1 was trapezoid.
> ...



I don't necessarily accept the idea that because it was done in the past that was the best way. It may have been the quickest or cheapest or more probably both but that doesn't make it best.

If drawer sides overfly the back then they have to be wider but more often if was the bottom which was the back stop.

I stick to my view that single kerf are OK on backs with less load and they need to be wider on fronts which get much hauling about.


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## GazPal (21 Mar 2012)

Modernist":2hmgy1cp said:


> I stick to my view that single kerf are OK on backs with less load and they need to be wider on fronts which get much hauling about.



Form follows function and dovetail dimensions are typically matched to suit the purpose of the piece within which they're used. This form can shift anywhere between elegant and robust and there is no hard and fast rule apart from being at the discretion of the designer and manufacturer.

In terms of aesthetics, production speed certainly influences cost, but the time factor can become a lesser consideration once aesthetics gain precedence over whether or not a piece can be used as a battering ram and pricing is gauged to suit whatever the market can bear.


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## Jacob (22 Mar 2012)

Modernist":2mkrshdu said:


> ....
> I don't necessarily accept the idea that because it was done in the past that was the best way. It may have been the quickest or cheapest or more probably both but that doesn't make it best.


It's not so much how they were done in the past but more about how they were done when the tradition was strongest. More activity and more ingenuity was being applied to the craft than at any other time before or since, in the Georgian/Victorian era. Which is a sweeping statement of course!


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## MatthewRedStars (22 Mar 2012)

Modernist":3i484phg said:


> I stick to my view that single kerf are OK on backs with less load and they need to be wider on fronts which get much hauling about.



Wider dovetails may be a lot stronger... but neither wide nor narrow will fail in normal use, or rough use probably, so its a moot point.


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## matthewwh (23 Mar 2012)

In modern furniture single and double kerf DT's have the advantage that they can't be machine cut and therefore make it easier to single the piece out as handmade.

Given that this is a better guarantee of future value than what could potentially be a set of machined pins with a knife line drawn across them I would suggest that although identical trapezoids may be marginally stronger, the further you can get from something that looks machined the better. 

If I were buying handmade furniture I would be looking for elements that single it out as handmade and therefore guarantee future value as opposed to an inefficient replication of machine made stuff.


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## Jacob (23 Mar 2012)

matthewwh":yjjtibkc said:


> In modern furniture single and double kerf DT's have the advantage that they can't be machine cut and therefore make it easier to single the piece out as handmade.


Completely wrong. It's the other way round. All machine cut DTs are double kerf (or look like them). Triangular single kerf pins can't be cut by machine as far as I know. The A&C style double kerf DTs can be faked on a machine.


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## mtr1 (23 Mar 2012)

Jacob":1e4xotps said:


> Triangular single kerf pins can't be cut by machine as far as I know. The A&C style double kerf DTs can be faked on a machine.



The pin holes can't be cut with a machine, the sockets can be hogged out with a router. This is how I cut mine, though I don't single kerf mine because I don't like that look.


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## bugbear (23 Mar 2012)

Jacob":2c2eb5dc said:


> The A&C style double kerf DTs



I'd have said (with some confidence, although I'm never as "confident" as Jacob) that the use of non-zero-width-apex pins is both wider and earlier than A&C?

BugBear


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## Jacob (23 Mar 2012)

bugbear":1apdmlcb said:


> Jacob":1apdmlcb said:
> 
> 
> > The A&C style double kerf DTs
> ...


Of course it is. Wider and earlier than A&C that is. 
It's that they seem to have fixed the style, or set the fashion somehow. 
I'm not saying that it's wrong - you can do what you like, but I am saying it's not "right" in any particular sense. The trade seems to agree as the single kerf pin seems to be generally favoured. Probably because it's easiest. Personally I quite like it too.


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## Jacob (23 Mar 2012)

Getting back to the topic of dividers. Tricks so far:
1 the offset line way of dividing another line, done with dividers and parallel rule or similar. NB easily overlooked design of parallel rule is the rolling rule - basically a long cylinder like a rolling pin which you just roll and hold steady for a parallel line.
2 with a scale applying the above to establish for example 15/14ths of an inch, so that you can mark up a 14tpi guide for saw sharpening, or any other regular spacing (equal sized DTs on a tool box?)
3 Alf's link, Robs description, Schwarzy's book, way of equally spacing for 2 kerf DTs and similar - shelf housing? This is presumably the same as DC's method (which he is being a bit coy about :lol: ).
4 What would be useful would be to do equal spacing as per 1 above but along the line without offset and parallel rules. Actually this is quite simple.
Benidorm has just come on so I'll carry on later.


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## David C (23 Mar 2012)

3. Dividers work for spacing both wider sockets and single entry sockets.

Alf's link did the job nicely....

David C


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## GazPal (24 Mar 2012)

Let's not forget the fact dividers work when setting out geometric shapes and patterns for structures as well as inlays and establishing proportion in pieces being worked upon or constructed. These forms can be as simplistic or complex as one desires and based upon whichever measuring system you wish to work to/use (Foot, cubit, yard, barley corn, metre, etc.) and when paired with the square. The use of dividers/compass is traceable as far back as history allows and they can be shop made, smith made or store bought, but are well worthwhile having amongst a tool kit.


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## Jacob (24 Mar 2012)

David C":17uwkzsm said:


> 3. Dividers work for spacing both wider sockets and single entry sockets.
> 
> Alf's link did the job nicely....
> 
> David C


Doesn't do single kerf DTs does he? I might have missed it, but not on page 2 either. http://www.mikes-woodwork.com/ThroughDovetails.htm
He's got some very fancy kit though, I wonder if he's a brain surgeon in ordinary life.

I'l have another look.


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## Jacob (24 Mar 2012)

OK had a look. He doesn't mention single kerf DTs but he does mention adjusting by trial and error. But in fact you can do better than that. You start with trial and error, but sharpen up on it.
Say you want to mark halfway between A and B. You adjust the dividers as near as you can, then starting at A ,walk them to B. 
If you miss B, error under or over, what you do next, without taking the point of the divder out of the approximate mid way mark, is adjust the other point to halve the error, as near as you can judge.
The do it all again starting at A. The error is reduced and may be zero. If not, you merely repeat the process, halving the error again,
You will probably hit it near enough 2nd time, more than 3 goes unlikely. 

If you want to divide into three you repeat the process as above starting with a stab at adjusting the dividers to a third. When you correct the error on the last step instead of halving it, you add or take away a third (as near as you can judge). Then repeat the process as often as you need. 2 or 3 goes should do it.

Then ditto for 4, you adjust the error by 1/4, and so on ad infinitum.

Sounds tedious but in fact you get a very accurate result surprisingly quickly.

There is an explanation of why it produces a quicker and more accurate result than you would anticipate, but it's a bit long winded!


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## David C (24 Mar 2012)

For single kerf marking, step across from half pin mark, to half pin mark, no overlap.

David C


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## Jacob (24 Mar 2012)

David C":d9c6sn82 said:


> For single kerf marking, step across from half pin mark, to half pin mark, no overlap.
> 
> David C


Yes obviously, but how would you set the dividers to achieve this?


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## David C (24 Mar 2012)

Well, obviously you do what you described in previous post.


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## Jacob (24 Mar 2012)

Right!

I'm quite pleased to have discovered dividers, although somewhat late in the day!
The other outcome of this thread (for me at least) is in realising that the offset ruler thing for setting out DTs as described by Joyce, and Wearing, is basically pointless and complicated. Dead stupid in fact! So if you have the books I recommend turning to the appropriate pages and making a note.
They get many things wrong in the books. That's OK nobody is perfect. But they get repeated and everybody gets it wrong.


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## Cheshirechappie (24 Mar 2012)

I think dividers can be quite useful on their own, but can be more useful when used in conjenction with other tools - rather in the same way that a marking knife is more useful used in conjunction with, say, a try-square or sliding bevel.

If dividers are used in conjunction with a sector (as Alf pointed out earlier in the thread),or with a good rule, they can do even more than if used on their own. They can make their own rule, of course - set dividers to any arbitrary length, step off along a clean, straight stick, return the marks all round the stick with square and knife/pencil, and voila - one homemade ruler!

What Jacob says about setting dividers by 'trial and error' is quick, and plenty accurate enough for most woodworking tasks. It isn't accurate enough for engineering tasks, but that need not concern the wood-only person at all. Wood doesn't work like metal, and doesn't behave like metal, so the techniques are different.

If anybody does need to set dividers accurately for some metalworking or similar purpose, they can be set within a couple of thousands of an inch by carefully placing the (sharp!) points in the engraved lines of a good quality steel rule. Adjust until the points drop neatly into the middle of each engraved line (the screw adjustable ones, used with a light touch, are useful here). You can either use a magnifier, or 'feel' the points in the line - hard to describe, but easy with a bit of practice and a light hand. Transfer the mark with delicacy and feeling - dividers are prone to flex if used with a heavy hand. This technique is not, of course, necessary for wood marking - the stuff will change dimension more than two thou if it comes on to rain the same afternoon!


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## Jacob (24 Mar 2012)

Cheshirechappie":advgwsu4 said:


> I think dividers can be quite useful on their own, but can be more useful when used in conjenction with other tools


 Yes no doubt but I was surprised at how much you can do with them on their own.


> What Jacob says about setting dividers by 'trial and error' is quick, and plenty accurate enough for most woodworking tasks. It isn't accurate enough for engineering tasks,


Oh yes it is! Or could be. That method for subdividing a length is potentially very precise - if the kit itself is precise enough. You would soon need a magnifying glass for fractioning the error and a pair of dividers capable of fine adjustment.
You start with trial and error but then set about eliminating the error.
You could say it's deceptively accurate. Deceptive because where i say "halving the error" (or thirding, quartering etc) you don't actually halve _the error on the divider setting_ (e.g. reduce it from 4 to 2mm), if you "halve" accurately you get zero error (e.g. reduce from 4 to 0) if you were a dead shot, but in fact realistically you would have another, but very much smaller, error.


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## Jacob (26 Mar 2012)

Got a pair of these http://www.axminster.co.uk/axminster-ax ... rod377322/
Somebody recommended them earlier. He must have been lucky, mine were rubbish, sending them back. Really badly made.

Have been practicing the error reducing technique on pieces of lined paper. If you get the first try near enough it only takes one more go to get it spot on (in woodworking terms). But two goes is the most you need. More for engineering precision (if you dividers are up to it; fine adjustment etc).
It's quicker than any other method by far.


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## Modernist (26 Mar 2012)

You'll be wanting a set of these then :lol: 

http://www.fine-tools.com/st306468a.jpg

A snip at €110


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## GazPal (26 Mar 2012)

Jacob":zj6vegs8 said:


> Got a pair of these http://www.axminster.co.uk/axminster-ax ... rod377322/
> Somebody recommended them earlier. He must have been lucky, mine were rubbish, sending them back. Really badly made.
> 
> Have been practicing the error reducing technique on pieces of lined paper. If you get the first try near enough it only takes one more go to get it spot on (in woodworking terms). But two goes is the most you need. More for engineering precision (if you dividers are up to it; fine adjustment etc).
> It's quicker than any other method by far.



Hit evil bay and you'll pick up a very decent old set for a few £. My son bid on an old adjustable 8" compass (Lockable with fine adjuster) made by Union and picked it up for less than £3 with postage and is now scribing circles and dividing everything in sight in the workshop. :lol:


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## Eric The Viking (26 Mar 2012)

Weird coincidence - just happened across this thread; finished making these last night:







I didn't make them to work as dividers especially, but there's room next to where the pencil fits in for a second spike (if I can find another masonry nail!). They open to about 13" (but you could use a longer pencil stub!).



E.

Edit: I'd probably glue a nail into a dowel instead (for the dividers). And you get various grades of line blackness too!


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## Jacob (31 Mar 2012)

Modernist":xpbuc257 said:


> You'll be wanting a set of these then :lol:
> 
> http://www.fine-tools.com/st306468a.jpg
> 
> A snip at €110


Thought about it (seriously - I'm into dividers!) and went for these instead.
They are OK. Cheap but work well - nifty quick release split collet thing which probably is the weakest link and won't last. Much better than Axminster's garbage. I now how have two Axi faulty offerings free of charge after full refunds as they didn't want them back. This suggests that the fact that they are rubbish has not escaped them. They shouldn't be selling them at all then, it's a sort of low level fraud - they know that some innocent punters will accept them in good faith.


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## Jacob (27 Apr 2012)

Revisiting this site - thought I'd look at Gunter scales 
http://www.nzeldes.com/HOC/Gunter.htm
but then its the diagonal scale which does the job
http://www.fullchisel.com/blog/?p=607
and enables you to take off measurements in inches and hundreths, or any other units and fraction, according to the design of the scale.
This'd be all you'd need to set dividers for any tpi saw measurement. What's more, given a drawing board, set square and a fine pen, you could draw your own.


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