# A quick question on skew chisels



## carlb40 (12 Jan 2014)

Just wondering if the angle of the skew makes a difference? I notice a lot of companies use a 20 degree angle, yet Narex state theirs are ground to 30 degrees.

The reason i ask is i will probably be getting some later in the year. More than likely Narex to go with my current set. But will make my own from some of their standard 8116 (natural) as i haven't seen any in those handles, just a horrible mid brown dyed version. :roll:


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## AndyT (12 Jan 2014)

Presumably you are not talking about a turning skew chisel?
There are two angles that could be mentioned to describe a skew chisel - the angle by which the cutting edge differs from straight across, and the angle by which the cutting edge is ground ( sharpened) which would normally be 30 degrees.

I can't see the need for skew chisels myself. I think they are quite a recent introduction.


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## Peter Sefton (12 Jan 2014)

The angle on the skew depends on what work you are looking to do with it, if it's only for cleaning out lapped dovetails 1:8 is about 8 degrees, 1:5 is about 11 degrees from memory. I am sure someone will correct me on those guesses. I have some of the Narex Premium Skew chisel's in the store room that I have re handled in Boxwood as I am also not so keen on the stained handles. They have never been used it was just a little study of mine in how you can improve the already good chisels by swapping handles, something we do on our 8112 Mortice chisels for those customers as fussy as me. PM me if we can help or as you say regrind 8116's to match at whatever angle (suits you sir) 
Cheers Peter


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## carlb40 (12 Jan 2014)

AndyT":f5hsfe0x said:


> Presumably you are not talking about a turning skew chisel?
> There are two angles that could be mentioned to describe a skew chisel - the angle by which the cutting edge differs from straight across, and the angle by which the cutting edge is ground ( sharpened) which would normally be 30 degrees.
> 
> I can't see the need for skew chisels myself. I think they are quite a recent introduction.


Sorry i should have stated the cutting edge rather than the bevel angle. 
I did google it, but all that came up was skew chisels for turning. :roll:


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## carlb40 (12 Jan 2014)

Peter Sefton":2lao1i0s said:


> The angle on the skew depends on what work you are looking to do with it, if it's only for cleaning out lapped dovetails 1:8 is about 8 degrees, 1:5 is about 11 degrees from memory. I am sure someone will correct me on those guesses. I have some of the Narex Premium Skew chisel's in the store room that I have re handled in Boxwood as I am also not so keen on the stained handles. They have never been used it was just a little study of mine in how you can improve the already good chisels by swapping handles, something we do on our 8112 Mortice chisels for those customers as fussy as me. PM me if we can help or as you say regrind 8116's to match at whatever angle (suits you sir)
> Cheers Peter



Thank you Peter. I'm not quite sure what they will be used for just yet. Could be used for general purpose cleaning up. I could have done with a pair today to make life easier chopping out for the spine in my saw handle LOL.

Not sure i would like the shiny premium chisels, they wouldn't match my standard 8116 ones  

I quite like the handles on the 8112's it suits them, seeing other versions with the handles from the 8116 series - they seem to be mismatched LOL


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## Peter Sefton (12 Jan 2014)

I also like to have sets of chisels that match, it shouldn't matter but it does  The 8112 with black handles are perfectly serviceable we have sets of them in our students tool kits and not many customers opt for the Boxwood versions but it offers choice if desired.
Cheers Peter


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## carlb40 (12 Jan 2014)

Cool so i'm not the only one who likes matching chisels 

Hmmmm you have got me thinking now on the handle front. I just rechecked the skew chisels on ebay and the handles are a different style to the 8116 natural. :-k


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## Cheshirechappie (13 Jan 2014)

Some time ago (can't remember when!) I asked why some manufacturers supply skew chisels with 45 degree skew angles - that's far steeper than lap dovetails need for cleaning out. The answer apparently is that some cabinetmakers like to clean up protruding tenons and such like after assembly with a paring chisel, and the 45 degree skew gives a cleaner finish. Left and right for opposite sides of the tenon, of course. Something of a specialist application, that one.

I've ground my skews at just over 10 degrees. In a fit of madness many moons ago, I equipped myself with a pair of 1/4" and a pair of 1/2". In retrospect, I'd have been better off with just one pair, of either 1/4" or 3/8". There again, I've only ever used them for lapped dovetails, never having incorporated a protruding tenon in anything!

Edit to add - something I've just remembered about 45 degree skews - the idea is so that the chisel blade and handle can be parallel to the carcase side (or whatever) whilst paring chamfers on protruding tenons and thus your hands are braced against the job. Using an ordinary chisel with the edge at 45 degrees to the tenon end would mean the handle being up in the air, so your hands could not brace against anything, so you run the risk of digging a corner of the chisel edge into the finished cabinet side.


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## David C (13 Jan 2014)

My 1/4" skew chisels are set at 1 in 6, which is the angle I use for carcass dovetails, as suggested by Joyce.

If you have a grinder, there is no need to buy anything special. Just modify regular chisels, (with care regarding overheating).

David Charlesworth


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## Jacob (14 Jan 2014)

Yes, or manage without them altogether, they are by no means essential.
It's easy to fall into the trap of thinking that because these things exist, they are necessary. No doubt they are available in sets! :lol:


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## Racers (14 Jan 2014)

You could knock one up from some Ground flat stock 




They are very handy things for half blind dovetails.


Pete


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## bugbear (14 Jan 2014)

Jacob":3g4membo said:


> Yes, or manage without them altogether, they are by no means essential.



Would you kindly describe your process of cleaning waste from the corners of lap dovetails?
On the face of it, there does seem to be an obvious difficulty, which is nicely addressed by some of the chisels described in this thread.

BugBear


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## carlb40 (14 Jan 2014)

Cheshirechappie":1dkbirkj said:


> Some time ago (can't remember when!) I asked why some manufacturers supply skew chisels with 45 degree skew angles - that's far steeper than lap dovetails need for cleaning out. The answer apparently is that some cabinetmakers like to clean up protruding tenons and such like after assembly with a paring chisel, and the 45 degree skew gives a cleaner finish. Left and right for opposite sides of the tenon, of course. Something of a specialist application, that one.
> 
> I've ground my skews at just over 10 degrees. In a fit of madness many moons ago, I equipped myself with a pair of 1/4" and a pair of 1/2". In retrospect, I'd have been better off with just one pair, of either 1/4" or 3/8". There again, I've only ever used them for lapped dovetails, never having incorporated a protruding tenon in anything!
> 
> Edit to add - something I've just remembered about 45 degree skews - the idea is so that the chisel blade and handle can be parallel to the carcase side (or whatever) whilst paring chamfers on protruding tenons and thus your hands are braced against the job. Using an ordinary chisel with the edge at 45 degrees to the tenon end would mean the handle being up in the air, so your hands could not brace against anything, so you run the risk of digging a corner of the chisel edge into the finished cabinet side.


Thank you.
One of the skew chisels i found was being used to clean up a tenon shoulder


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## carlb40 (14 Jan 2014)

David C":2ltj4j9r said:


> My 1/4" skew chisels are set at 1 in 6, which is the angle I use for carcass dovetails, as suggested by Joyce.
> 
> If you have a grinder, there is no need to buy anything special. Just modify regular chisels, (with care regarding overheating).
> 
> David Charlesworth


Thank you David. I had no intention of buying skews, as said my intention would be to grind my own


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## carlb40 (14 Jan 2014)

Racers":2s1ygizg said:


> You could knock one up from some Ground flat stock
> 
> 
> 
> ...


Thank you Pete.

I don't really like the look of fishtails  I know it shouldn't make a difference, but it does.


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## carlb40 (14 Jan 2014)

bugbear":1ipu6txx said:


> Jacob":1ipu6txx said:
> 
> 
> > Yes, or manage without them altogether, they are by no means essential.
> ...


Pretty sure he covered that last year in one of the sharpening/ out of square edge threads. 

I started this thread to ask on specific skew angles. If jacob wishes to answer your question, he can start his own thread on it.


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## Jacob (14 Jan 2014)

Take my word for it - it can be done.
Have a go yourself, I guess you never have done a blind dovetail socket.


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## bugbear (14 Jan 2014)

carlb40":3jtcguyo said:


> bugbear":3jtcguyo said:
> 
> 
> > Jacob":3jtcguyo said:
> ...



It's very rare for Jacob to actually describe technique - and a quick google doesn't show anything positive.



carlb40":3jtcguyo said:


> I started this thread to ask on specific skew angles. If jacob wishes to answer your question, he can start his own thread on it.



Jacob says the correct angle is 90 degrees. ;-)

BugBear


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## Jacob (14 Jan 2014)

bugbear":1l285p8f said:


> .....
> Jacob says the correct angle is 90 degrees. ;-)
> 
> BugBear


No I didn't say that. You are getting in to troll mode again BB - have you stopped taking the pills?


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## bugbear (14 Jan 2014)

Jacob":2q4xgirf said:


> bugbear":2q4xgirf said:
> 
> 
> > .....
> ...



I could simply do without your repeitive negativity:



Jacob":2q4xgirf said:


> .. I will keep banging on in the same vein, 'til the cows come home!



BugBear


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## carlb40 (14 Jan 2014)

bugbear":3ov1o1u7 said:


> Jacob":3ov1o1u7 said:
> 
> 
> > bugbear":3ov1o1u7 said:
> ...


We all could do without that.

However i started this thread for a specific reason, and that has been answered / explained. 

I did not start this thread for whether such chisels are needed or can be done with normal chisels. If you both wish to continue, please take it to another thread. 

If you both continue in here i shall request the thread be deleted.


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## David C (14 Jan 2014)

Acute corners may be cleared with an 1/8" chisel. The amount of undercutting is negligible.

David Charlesworth


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## Corneel (14 Jan 2014)

carlb40":1ugm4kig said:


> However i started this thread for a specific reason, and that has been answered / explained.



If your question heas been answered allready, why do you bother if the thread takes another turn? Thread drift is normal in forums. And the OP doesn't really OWN the thread.


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## Jacob (14 Jan 2014)

David C":tif8gkor said:


> Acute corners may be cleared with an 1/8" chisel. The amount of undercutting is negligible.
> 
> David Charlesworth


Yes. Or wider in fact. Not necessarily text book perfect but they hardly ever are - if you have the chance to look at a drawer DT socket on a typically trad (even high quality) piece they are often fairly untidy, with chisel marks and a lot of undercutting. It's a compromise between finished appearance and speed of production and the bits nobody is supposed to see don't matter at all.
So _an_ answer to the OPs question - any angle _might_ do the job one way or another but, if you want a skew, approximately 30º is a good for a lot of things.

PS IMO the reason why these threads get conflicted is that the answer to many woodwork questions is not always specific; it's not like engineering where a mechanic's socket set has to be spot on with the right sizes all arrayed in tidy rows.


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## Paul Chapman (14 Jan 2014)

David C":27ow6mhu said:


> If you have a grinder, there is no need to buy anything special. Just modify regular chisels, (with care regarding overheating).



I did exactly that. Bought two very inexpensive sets from Lidl and ground them quickly on my Tormek. They are not something that I'd use a lot, so didn't think it was worth buying expensive ones.





Cheers :wink: 

Paul


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## Carl P (14 Jan 2014)

I'm really sorry about this, but I'm going to have to ask _thatquestion - polite and sensible replies please, but what are the favoured methods of sharpening, I only ask because Paul's look so beautifully done,

Cheerio,

Carl_


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## Jacob (14 Jan 2014)

Carl P":19h3ql1a said:


> I'm really sorry about this, but I'm going to have to ask _thatquestion - polite and sensible replies please, but what are the favoured methods of sharpening, I only ask because Paul's look so beautifully done,
> 
> Cheerio,
> 
> Carl_


_No different from any other chisel (why would it be?) so mine would be freehand on an oil stone - not so beautifully done, but quickest and easiest._


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## CStanford (15 Jan 2014)

bugbear":3is35ujt said:


> Jacob":3is35ujt said:
> 
> 
> > Yes, or manage without them altogether, they are by no means essential.
> ...



An eighth inch chisel. Doesn't even need to be a bevel-edged chisel. The last tenacious little bits clinging in the corners can even be picked out with an awl. Most of the time a quarter inch chisel works just fine. Tail sockets are big allowing a lot of scope for changing the angle of attack to get the last little bits. Nothing hard at all.

In stringy woods tap a thick scraper or old bandsaw blade in the saw cuts to finish the cut into the corner of the half laps. See Tage Frid. Saves much time in wood that doesn't chisel cleanly. Done correctly, the corners will almost be dead clean. Some will be, others will have only a small amount hanging that's been severed from the tail wall. A straight cut in releases this bit and is easily done with a quarter inch chisel or even larger chisel.


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## Derek Cohen (Perth Oz) (15 Jan 2014)

For cleaning out the corners of half blind dovetails, I prefer a fishtail chisel over a skew. The skew cuts on the slice and the fishtail cuts on the push, which is much easier ..







While one could possible use any small chisel (1/8" is better) to clear these corners by undercutting, you cannot undercut when there is little separating the pins, such as in very fine dovetails ...






Clearing the corner is so much easier if there is a release cut. Tage Frid used to hammer a bandsaw blade into the corner. Some use a scraper blade to do so. I built a dedicated "kerf chisel" ...






Link to build one: http://www.inthewoodshop.com/ShopMadeTo ... hisel.html

Regards from Perth

Derek


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## Peter Sefton (16 Jan 2014)

I agree that using a Fishtail is much better for Lapped Dovetails. Ashley Iles are making this Square End Fishtail chisel for the tool shop. I would rather use a single Fishtail than use a left and right handed skew for such work much more productive IMO.
Peter


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## bobbybirds (16 Jan 2014)

These days I always reach for my fishtail for half blinds as well, but 1/8th inch bevel edge works just fine as well...


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## David C (16 Jan 2014)

Peter,

I wonder what the angles are on that fishtail chisel?

From the photo they don't look as if they would get into the corner of a 1:6 socket.

Derek, I don't like to undercut the base of the pins, no matter how fat, but I do undercut the base of the lap. Seems safer!

The nice thing about a regular skew chisel is that it slides along the side of a pin without damage, if one is careful with cutting direction.

best wishes,
David Charlesworth


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## Peter Sefton (16 Jan 2014)

Well spotted David they would be a little tight to fit 1:6 Dovetails, they will do 1:7 or 1:8. 
IMO Dovetails in hardwood should be fine and slender 1:7 to 1:9 to look right 1:8 as a standard, I feel 1:6 and 1:5 are for softwoods and I see no merit in cutting one of our most expensive joints in the cheapest timbers. We do also stock left and right skew chisels and sets of Dovetails chisels if people desire them. I always try to advice my students to spend their money wisely every tool they buy should pay it's way. As said before a 3mm chisel will cope well in the corners with only minor under cutting but it does leave the sockets a little untidy. 
Cheers Peter


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## Jacob (16 Jan 2014)

Peter Sefton":200p15eb said:


> .....
> IMO Dovetails in hardwood should be fine and slender 1:7 to 1:9 to look right 1:8 as a standard, I feel 1:6 and 1:5 are for softwoods and I see no merit in cutting one of our most expensive joints in the cheapest timbers. .....


Historically they weren't "our most expensive joints" but were merely the normal way to join drawer fronts to sides, or box corners, etc. in cheap or expensive timbers. There weren't many alternatives. 
All the waffling about angles is just a modern affectation - you will find many variations in old furniture - especially the hand made "production line" stuff where the makers were under pressure to be cost effective. 
You can find out a lot about how to do things by _looking_ at stuff - IMO people don't look at stuff enough, and it really shows - the difference between 1:6 and 1:5 is so little as to be meaningless. If you take the trouble to actually look you will find DTs varying from 1:2 through the whole range to to straight "box" joints.
Give yourself a break - start _looking_ at stuff! You have nothing to lose!
Also try _thinking_ about it - logically hardwoods being generally stronger could take a steeper DT angle than weaker softwoods. The popular view is quite opposite, and basically nonsense.
Suggestion for new years resolution - in 2014 make more effort to _look_ at things and _think_ about them!


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## bugbear (17 Jan 2014)

George Ellis 1908":193debst said:


> Angle of Dovetails - there is a tendancy amongst the inexperienced to make
> the angles of the sides too acute. Such dovetails, though appearing strong,
> are really weaker than if cut more nearly parallel.



Ellis describes a DT marker with an 80 degree angle, which is around good old 1:6

Mind you, Jacob said this concern with angles was a modern thing, and Ellis' book
is indeed called "Modern Practical Joinery" 

Ian Kirby (who is modern) points out that in many scenarios
a DT joint is so very much stronger than what is actually required
that a very great deal of design flexibility is allowed, which he suggests
can be exploited for aesthetics.

BugBear


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## Jacob (17 Jan 2014)

But what you find if you look at stuff is that the majority of makers obviously didn't obey these little rules. I find it endlessly fascinating how the text book or armchair theory of how things "should" be done is at variance with how things actually were done. Nothing wrong with text books and rules of thumb of course - everybody has to start somewhere.


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## MMUK (17 Jan 2014)

Having looked at the differing options and opinions here, I think I would tend towards dovetail chisels purely to save myself time in putting down a LH skew to pick up a RH one. Having said that, I'd still equip myself with a set of LH and RH skews as I like to have every eventuality covered. I may have to take a trip to Lidl :lol:


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## David C (17 Jan 2014)

Peter,

Thank you.

Joyce suggests 1:6 for carcase work where the joints may be hidden, also secret miter and double lap.

I would agree that exposed pins, such as drawer fronts, look better with less slope. However with thin stuff, say 5/16" or 8 mm, the through dovetails at drawer backs benefit from 1 : 6 as 1: 8 looks barely sloped at all.

These are just my personal choices.

David


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## MMUK (17 Jan 2014)

Personally I don't look into specific gradients for dovetails, I generally sketch them out to a rough scale and decide what looks best if they are going to be seen or what's best structurally if not.


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## Derek Cohen (Perth Oz) (17 Jan 2014)

Hi Jacob

Personally, I see no issue with the way anyone wants to cut dovetails. I agree with you and I agree with BB - see, I am flexible! :lol: 

If one wants to replicate the dovetails that were used by those in past centuries, then do so. I suspect that you will find that they varied, however. I'm not a historian, so am open to correction (hey, I'm always being corrected!). 

I do view the "modern dovetail" to be just that, but it has become one feature by which standards are judged - just as much as you consider that they are not where standards should be judged. It's just the present day focus. By present day I do not mean the last 10 - 20 years. I think you will find examples of finely cut dovetails going back at least 100 years, so the "modern" emphasis is not that recent. Perhaps the focus on them is more modern - Alan Peters was shaping his dovetails with care in the 60s, and he apprenticed to Edward Barnsley. 

The slim "London" style dovetails (where on Earth did that name come from - is there a more appropriate name?) that were a feature of Alan Peter's drawers are just one example of the focus placed on dovetails as a design element. Another is the influence of Jim Krenov. He combined the structural (placement and spacing) with the aesthetic (make it interesting). 

My theory is that one draws attention to workmanship either through attention to details such as mouldings and other intricate carvings such as ball-and-claw feet, which were more prominent 100 years ago, or we find some other focus. The current _zeitgeist_ appears to have been influenced by the Shakers, Danish and other contemporary stylings which seem to be dominated by their silhouette instead.

Regards from Perth

Derek


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## Jacob (17 Jan 2014)

Derek Cohen (Perth said:


> Hi Jacob
> 
> Personally, I see no issue with the way anyone wants to cut dovetails. I agree with you and I agree with BB - see, I am flexible!


Glad to hear it!


> If one wants to replicate the dovetails that were used by those in past centuries, then do so. I suspect that you will find that they varied, however. I'm not a historian, so am open to correction (hey, I'm always being corrected!).


You don't have to be a historian you just need to look at stuff. It's a habit well worth adopting.


> ..
> The slim "London" style dovetails (where on Earth did that name come from - is there a more appropriate name?)


I think of them as "single kerf" dovetails. The position of each pin hole is marked up freehand with a single saw cut freehand, and the saw dropped into the same kerf to cut the 2 sides. It's quick, easy, and very common in items where strength isn't a big issue, such as lightly loaded drawers.

DTs are used for two principle reasons - they are self locating so clamps are not necessary, and they divide up the joint so that any movement won't necessarily translate itself to the whole joint. A sort of "stitching" - you get a similar effect with glue blocks, where a lot of short ones makes a stronger joint than one long one. Or a lot of small nails is stronger than one large one etc.



> My theory is that one draws attention to workmanship either through attention to details such as mouldings and other intricate carvings such as ball-and-claw feet, which were more prominent 100 years ago, or we find some other focus. The current zeitgeist appears to have been influenced by the Shakers, Danish and other contemporary stylings which seem to be dominated by their silhouette instead.


Or workmanship as opposed to design. A good point - there's a lot of stuff out there which is beautifully made but still very boring. And vice versa - good design with poor workmanship. Personally I rate design above all. If it's well made that's a bonus!


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## Cheshirechappie (17 Jan 2014)

Jacob":umgnd4ut said:


> Peter Sefton":umgnd4ut said:
> 
> 
> > .....
> ...



Imagine pulling a drawer front off the sides. For this to happen, the dovetails must fail. There are (at least) two failure mechanisms. The first is by shearing off the angled part of each tail - long-grain failure of the wood. That's more likely if the wood is hard and brittle, or if the dovetail angles are steep leaving short-grain. The second is failure by crushing wood fibres allowing the tail to pass the pins, a failure more likely in softer wood and with shallower dovetail angles.

I think there are good pragmatic reasons for softwood dovetails to be cut at a steeper angle than hardwood ones, and the 1:6 (or thereabouts) angle is a good compromise between insurance against failure by crushing and failure by short-grain breakage. In hardwoods, failure by crushing is less likely, but failure by short-grain breakage is possible so a shallower 1:8 (or thereabouts) angle is a pragmatic one. I think it's taken a long time and much experience for craftsmen to settle to those angles as about the best compromises, and they've done so for good reason - a lot of collective experience over several generations.

Looking at old work can be very instructive, but one has to be careful not to regard everything done in the old days as automatically right or best practice. Anybody involved in the restoration of old buildings, machinery or whatever will be well aware of examples of what would not be regarded as best practice nowadays. Sure, some old examples of poor practice have survived, but we don't always know how many examples didn't survive, because they were poor practice!


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## Jacob (17 Jan 2014)

Cheshirechappie":3vc18hda said:


> ........
> Looking at old work can be very instructive, but one has to be careful not to regard everything done in the old days as automatically right or best practice. Anybody involved in the restoration of old buildings, machinery or whatever will be well aware of examples of what would not be regarded as best practice nowadays. Sure, some old examples of poor practice have survived, but we don't always know how many examples didn't survive, because they were poor practice!


If it has survived that's one indication of good practice. Not reliable of course; the Georgians were notorious for cheapskate buildings which are still with us because maintenance is cheaper than replacement.


> I think there are good pragmatic reasons for softwood dovetails to be cut at a steeper angle than hardwood ones, and the 1:6 (or thereabouts) angle is a good compromise between insurance against failure by crushing and failure by short-grain breakage.


Sounds logical, but as I say - if you look at stuff you find that it's not that simple. I have some old pine drawers with DT gradients approaching 1:2 and they have survived intact for 100 or more years, even though this particular chest of drawers was left out in an open sided shed for many years .


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## xy mosian (17 Jan 2014)

As the conversation has drifted to Dovetail angles.
Here we have the largest collection of dovetails I have in any one piece. My Grandfather's Chest. Made, most likely, in the last few years of the 1800's. The height of the corner, of the chest, is 19", 480mm.
As you can see there is some variation in both the angle of the Dovetails and the mean angle of the tails to the edge.
xy


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## Jacob (17 Jan 2014)

Brilliant! Instead of theorising actually looking at stuff is really interesting and informative!
Every DT freehand I guess.


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## CStanford (17 Jan 2014)

xy mosian":3np1oof8 said:


> As the conversation has drifted to Dovetail angles.
> Here we have the largest collection of dovetails I have in any one piece. My Grandfather's Chest. Made, most likely, in the last few years of the 1800's. The height of the corner, of the chest, is 19", 480mm.
> As you can see there is some variation in both the angle of the Dovetails and the mean angle of the tails to the edge.
> xy



They certainly have a lot more verve than today's dovetails that strive for so much precision and regularity they may as well have been cut by machine.


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## Cheshirechappie (17 Jan 2014)

Jacob - a great many modern 'authorities' suggest that dovetail angles of about 1:6 for softwoods and about 1:8 for hardwoods are regarded as good practice. Now, I'm not saying they're 'right' or 'wrong', but those two approximate angles do seem to crop up quite regularly. Why has this become so, do you suggest?


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## Jacob (17 Jan 2014)

Cheshirechappie":3ldrdguk said:


> Jacob - a great many modern 'authorities' suggest that dovetail angles of about 1:6 for softwoods and about 1:8 for hardwoods are regarded as good practice. Now, I'm not saying they're 'right' or 'wrong', but those two approximate angles do seem to crop up quite regularly. Why has this become so, do you suggest?


Good question. I think the answer may be that someone was asked to be definitive about it at some point, a teacher or a writer perhaps, and his arbitrary suggestion went viral and has been repeated ever since. It'll do as an answer and there is a sort of logic to it, but there is no reason to stick to it. Slightly mad in fact - would it make the slightest difference if everyone did 1/7 instead? Of course not.


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## Cheshirechappie (17 Jan 2014)

Jacob":kil6unx2 said:


> Cheshirechappie":kil6unx2 said:
> 
> 
> > Jacob - a great many modern 'authorities' suggest that dovetail angles of about 1:6 for softwoods and about 1:8 for hardwoods are regarded as good practice. Now, I'm not saying they're 'right' or 'wrong', but those two approximate angles do seem to crop up quite regularly. Why has this become so, do you suggest?
> ...




In other words, you haven't a clue why.

I think I'll stick to my theory (I don't have a problem with theorising - it's what sets humankind apart intellectually from all other species) that over several centuries of collective and accumulative experience of using dovetail joints in wood, those are roughly the angles that work best for strong, lasting joints.


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## bugbear (17 Jan 2014)

Some research reveals that the January 1958 issue of Woodworker published the results of actual experiments at the Forest Products Research Laboratory, by K.S.Walker on dovetail angle versus joint strength.

http://www.amgron.clara.net/dtailtest32.html

BugBear


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## Jacob (17 Jan 2014)

Cheshirechappie":nbiq97mj said:


> ......
> I think I'll stick to my theory (I don't have a problem with theorising - it's what sets humankind apart intellectually from all other species) that over several centuries of collective and accumulative experience of using dovetail joints in wood, those are roughly the angles that work best for strong, lasting joints.


If they are the best angles then why did so many people not use them and produce furniture which survives still?
BBs article is interesting. A completely unrealistic test of DTs. As anybody who has looked at old furniture can tell you - DTs fail by being forced outwards sideways when glue fails or there is too much stuff packed in the box/ drawer etc. I doubt many ever fail by being pulled in the way shown. In any case the tests were on machine made DTs which are particularly weak in the sideways way, which wasn't tested.
People like definitive answers to questions. The choice of 1/6 or 1/8 gives the illusion of precision. People like appearing to be authoritative by quoting particular figures - just think of all the sharpening bevel discussions!
PS As for theorising - you don't need to theorise if you can look at stuff instead.
Failing DTs usually by spreading (see above) in which case the angle isn't going to make the slightest difference. But the _number_ of DTs presumably would - the more there are the more the glued surface area.


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## MMUK (17 Jan 2014)

Don't mention the S word Jacob!


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## Cheshirechappie (17 Jan 2014)

Jacob":323mp4vl said:


> Cheshirechappie":323mp4vl said:
> 
> 
> > ......
> ...




I did think about doing a full, point-by-point answer, but since most of the points you raised in this post have been dealt with earlier in the thread or by the research presented in Bugbear's link, to do so would just be going round in circles having an argument for the sake of it, and frankly I can't be bothered with that.

One point raised was not dealt with earlier. It's quite true that most dovetail joints are likely to fail by coming apart the way they went together, but as the discussion was about dovetail angles, it's irrelevant anyway.


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## Peter Sefton (17 Jan 2014)

Jacob":622gc9yy said:


> Peter Sefton":622gc9yy said:
> 
> 
> > .....
> ...




Jacob you do make me laugh - your comedic value is worth so much. I may put the idea of "looking and thinking" to others who teach just incase they had never considered that as a learning opportunity :lol:
I may borrow your idea if I may about using our past masters work to see if we can learn any thing and I will inform my students that they may cut dovetails at any ratio between 1:2 up to 1:8 it doesn't matter its all been done before so there is no best practice. :roll: 

Now I have "looked" at my collection of drawers I did notice that the lap Dovetails tend to be slender 1:8 and fine whist the back through Dovetails tend to be steeper 1:6, a cheaper quicker joint never really seen and a of course not requiring a Fishtail or Skew chisel. The carcass Dovetails do also tend to be steeper 1:6 but again are constructional not not to be seen or judged by the customer or used as a factor in the perceived value of a finished item, this is a factor that has not changed with history unlike our craftsman's wage packet and expected standard of living.
You may wish to hand cut your Dovetails at a steep angle but feel you will struggle to find your customer base within the fine furniture market, but possibly this is my historic customer base not yours.
I look forward to your next gems of wisdom Cheers Peter (with tongue severely in cheek)


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## Jacob (17 Jan 2014)

Peter Sefton":3u9svtkb said:


> Jacob":3u9svtkb said:
> 
> 
> > Peter Sefton":3u9svtkb said:
> ...


What makes me laugh is the cautious, conservative, timid, idea of best practice which is just made up with no relationship to practical needs. The craft woodworking "establishment" is a very closed and inward looking world.
Yes you should tell your students to experiment with different angles, and experiment in general. They might come up with something interesting. You should also tell them to look at stuff and not take anything for granted.
Your "customer base" is what you choose it to be. It seems that a lot of our cautious arts n crafts followers end up having to teach, or desperately sell people tools they don't really need. :lol:


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## bugbear (18 Jan 2014)

Jacob":3se5qr83 said:


> Yes you should tell your students to experiment with different angles, and experiment in general. They might come up with something interesting.



More likely they'll waste a lot of time reinventing the wheel. I would not look kindly on a teacher who led me down such a garden path.

Surely students should carefully copy historic best practice before inventing their own ideas...

BugBear


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## Jacob (18 Jan 2014)

bugbear":1ap88k10 said:


> Jacob":1ap88k10 said:
> 
> 
> > Yes you should tell your students to experiment with different angles, and experiment in general. They might come up with something interesting.
> ...


Basic principle of good design education and practice is to diverge and consider all possibilities and then converge on the end product, which may take you back to the idea you first thought of, or on the other hand perhaps to pastures new.
The term "best practice" is another of those odd viral ideas which get kicked about and probably gets in the way more often than not. As though there is holy text of "best practice".


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## bugbear (18 Jan 2014)

Jacob":ionpnhty said:


> bugbear":ionpnhty said:
> 
> 
> > Jacob":ionpnhty said:
> ...



I find standing on the shoulders of giants a good route to getting things done without flailing around in blind alleys

Perhaps you think maths students should discover calculus for themselves, instead of blindly following Newton/Leibniz?

BugBear


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## Peter Sefton (18 Jan 2014)

I think I recall a C&G multi guess question
What is the preferred angle for Dovetails in deciduous timber?

1. 1:5
2. 1:8
3. 1:2
4. Whatever


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## Jacob (18 Jan 2014)

bugbear":wjmib94e said:


> ......
> I find standing on the shoulders of giants a good route to getting things done without flailing around in blind alleys./...


Yebbut which giants? Old Jim Krenov? IKEA? Come to think IKEA would be better for design than St Jim.
If people didn't bravely flail around in apparently blind alleys (including Newton) there would be no progress at all.


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## Jacob (18 Jan 2014)

Peter Sefton":2t12a9qf said:


> I think I recall a C&G multi guess question
> What is the preferred angle for Dovetails in deciduous timber?
> 
> 1. 1:5
> ...


So where is your 1/6? What's wrong with 1/4? Answer: nothing at all.


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## MMUK (18 Jan 2014)

Jacob":uit8fs16 said:


> Peter Sefton":uit8fs16 said:
> 
> 
> > I think I recall a C&G multi guess question
> ...




In that case my little baboon, you select #4 as your answer :wink:


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## Jacob (18 Jan 2014)

MMUK":45febhmc said:


> Jacob":45febhmc said:
> 
> 
> > Peter Sefton":45febhmc said:
> ...


In fact the question doesn't make any mention of by whom preferred and is unanswerable. But "whatever" wouldn't really do. And baboon yourself!


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## MMUK (18 Jan 2014)

Jacob":3016foef said:


> In fact the question doesn't make any mention of by whom preferred and is unanswerable. But "whatever" wouldn't really do. And baboon yourself!




Maybe you should be contacting the City & Guilds to complain to them then? :mrgreen:


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## bugbear (18 Jan 2014)

MMUK":2ob55yul said:


> Jacob":2ob55yul said:
> 
> 
> > In fact the question doesn't make any mention of by whom preferred and is unanswerable. But "whatever" wouldn't really do. And baboon yourself!
> ...



One does feel sympathy for the tutors who tried to teach Jacob at college.

BugBear


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## Jacob (18 Jan 2014)

bugbear":2fx20z34 said:


> MMUK":2fx20z34 said:
> 
> 
> > Jacob":2fx20z34 said:
> ...


We were taught to freehand cut at anything less than 30º to the perpendicular (1/2) but to keep it as neat and regular as poss - which I think was very good advice. I have seen them done at higher angles approaching 45º but there is the danger of corners chipping off if you make a habit of it.


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## Peter Sefton (18 Jan 2014)

It is good when you have a group of students of mixed ages and abilities, they asked searching questions and the whole group benefits exploring the reasons that we reached general conclusions over the centuries. But what you don't need within the group is a four year old that keeps asking WHY? When the rest of the group has moved on.

I take on board your comments
"Your "customer base" is what you choose it to be. It seems that a lot of our cautious arts n crafts followers end up having to teach, or desperately sell people tools they don't really need."

What I need to do is let the students go through the long learning curve of self-discovery of what may be good or poor construction and advise them the will need to purchase a range of Dovetail templates to suit the various angle available and a set of different sized skew and Fishtail chisels. This may well be advantageous to both parties, or I may stick to my advice based on my past mistakes, experience and ill-advised tool purchases. :mrgreen:


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## MMUK (18 Jan 2014)

Peter Sefton":22f8dm7p said:


> It is good when you have a group of students of mixed ages and abilities, they asked searching questions and the whole group benefits exploring the reasons that we reached general conclusions over the centuries. But what you don't need within the group is a four year old that keeps asking WHY? When the rest of the group has moved on.
> 
> I take on board your comments
> "Your "customer base" is what you choose it to be. It seems that a lot of our cautious arts n crafts followers end up having to teach, or desperately sell people tools they don't really need."
> ...




Personally I think you should be maximising profits by advising your students to buy at least one of every item in your shop. Then they can go out into the big wide world with Jacob and take on every job without worrying that they don't have the right tools. Of course, they will then be under direction of the Dovetail Master himself :wink:


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## John15 (18 Jan 2014)

MMUK,
A good number of your posts are offensive and distasteful. I would be more interested to read your personal experiences in cutting dovetails and your more precise views on the various angles that the experts are discussing.
Cheers,
John


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## Jacob (18 Jan 2014)

MMUK":2nefo9ah said:


> Peter Sefton":2nefo9ah said:
> 
> 
> > It is good when you have a group of students of mixed ages and abilities, they asked searching questions and the whole group benefits exploring the reasons that we reached general conclusions over the centuries. But what you don't need within the group is a four year old that keeps asking WHY? When the rest of the group has moved on.
> ...


I tend to agree. Not sure abt the dovetail master bit, I don't want them all bothering me, they can all fff orf!

Anybody reading this - YOU DON'T NEED TO BUY A DOVETAIL JIG. You can freehand them very easily but if in doubt use a normal sliding bevel - and you only need one. Or just make a jig from a few scraps if you feel really inadequate and feeble minded.


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## MMUK (18 Jan 2014)

John15":zcyh9vd2 said:


> MMUK,
> A good number of your posts are offensive and distasteful.




Would you care to elaborate with examples please?


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## Peter Sefton (18 Jan 2014)

You are right Jacob, you can cut them free hand by eye, this will be the quickest way but untidy, you can use a sliding bevel my students boxes all have Marples which I get them to use as they learn the process for setting the (1:8) ratio or 1:4 if they wish to replicate early furniture. 
The sliding bevel is the traditional way but cumbersome to use and watch out you don't take your eye out on the sharp end :!: 
The students also make a brass Dovetail templates but I personally use and promote the cheapest Veritas 
http://www.brimarc.com/products/Veritas ... -22792.htm 
It is not as designer as the more expensive ones out there but I think it the best to USE :!: 
I won't send the students up for your Dovetail master class, just the sharpening :wink: 
Cheers Peter


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## Jacob (18 Jan 2014)

http://www.brimarc.com/products/Veritas ... -22792.htm What a ludicrous expensive bit of tat! Would anybody be mad enough to buy one?


> The sliding bevel is the traditional way but cumbersome to use and watch out you don't take your eye out on the sharp end


The sliding bevel is one of the easiest tools to use and it's adjustable to any angle. If you are seriously at risk from the sharp end (already blind?) you can turn it round to the blunt end. 
I think it's appalling that people are discouraged from using these simple and elegant traditional tools in favour of expensive and less useful American novelties.
NB if you use a sliding bevel DO NOT BUY the Veritas bevel setting protractor - it is amongst the most useless of all the novelty tools. A plastic school protractor will do a better job.



> you can cut them free hand by eye, this will be the quickest way but untidy,


 A bit of practice will be required, on a few scrap pieces. In any case cutting to a line will be untidy at first for most beginners. It's important to not de-skill them right from the start - too many jigs and gadgets and they will never get the hang of it. It's also important to get them to buy wood rather than tools they don't need.


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## Racers (18 Jan 2014)

Here we go again! its all kicking off.

For Pete's sake any one can use any tool and angle WITHOUT being singled out.

Mods step in please.

Pete


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## Jacob (18 Jan 2014)

Racers":2a9wag65 said:


> Here we go again! its all kicking off.
> 
> For Pete's sake any one can use any tool and angle WITHOUT being singled out.
> 
> ...


You can do what you like Pete but this discussion is about what you should recommend/sell to beginners


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## CHJ (18 Jan 2014)

Thread locked at request of OP.

Once more the usual antagonists have done their level best to spoil things for the OP and everyone else.


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