dovetail jig

[Jacob]

Pin(holes) first is the same as tails first.
I suppose if you had a rebate the drawer side would fit tight against the drawer front whilst marking through for the pins , but I've never seen this in old work so guess it's just another amateur woodwork tip. The hacks have to keep coming up with new tricks!

 

[JonnyW]

Jacob, you're right there. But isn't it fun reading in every new expensive issue, how they've successfully reinvented the wheel?.

Jonny

 

[AndyT]

Lurching back to the original suggestion about a jig to use on thin stock...

Nowadays, like lots of others who have already replied, I like to cut dovetails the quiet way. But a while back (fifteen years or more) I bought a little 1/4" Bosch router and explored ways of using it.

I made a few little boxes like this, from 9mm ash, and did the dovetails using the router.

I made this very simple jig. I've looked back at a book I had at the time, and I think it was probably intended as a very economical copy of one of the Keller jigs. It's designed to be used with a hand held router, dovetail cutter, and a guide bush.

You clamp the workpieces vertically against the cross-bar, with a bit of sacrificial wood in between. The slots are long enough to hold four pieces at a time (the four sides of a box). With the cutter projection set to suit the thickness of the wood, follow the slots to cut out the tails on the ends of the boards. At the time I used this jig, I would have used a Workmate for the clamping but a proper vice would do if it was wide enough.

That produces a set of finished tails. Mark the pins from these as if making by hand. Saw the sides of the pins, inside the waste, by hand or by bandsaw.

Then clamp a pair of boards back to back so the narrow sides of the waste are together. You don't need a jig for this. A workmate is suitable as it provides extra horizontal surfaces which help make the base of the router stable. Using a small straight cutter, remove most of the waste. These cuts are made to full depth. You can go up near the sawcut, leaving a wisp of wood to cut off with a small knife. Or with practice, you can guide the cutter into the kerf but stay the right side of it, especially if your saw cuts are not made with an extra-fine dovetail saw but with something cheaper or the bandsaw. This sounds harder than it is but you soon get used to keeping the router cutter inside the waste.

The result should be some decently-fitting dovetails. I only ever made the one jig, but they are quick and easy, so you could make one to suit the scale of your boxes. You can of course vary the spacing, though you can't go much thinner than these because of the diameter of the router cutter.

 

[woodbrains]

Hello,

A couple of observations; running a slight rebate on on board gives a positive location for setting the other board against when transferring marks. It was not (widely) done on old work because they did not have the speed and accuracy of a router table to do so. It is a useful method for accuracy (for those who want to) so why should we not? It is ludicrous to argue that because it was not seen on old work that we should not, if we feel the need, when the truth is, it wasn't done becuse it couldn't have been. There is such a thing as progress! Of course if you don't want to, then don't, we have a choice.

The origin of this sort of rebate predated Chris Schwartz 'discovery' anyway. I don't know exactly who did it first and how long ago, but I tried it for curiosity about 15 years ago from something I read (not Schwartz). I suspect these things were done longer ago than any one cares to think. I would bet someone tied it with a knife and rebate plane, at some point in the distant past. You could not tell by looking at old stuff, anyway, you would have to break every piece apart to see. Whilst I agree it was not normally done, no one can say it was never done.

Tage Fridd was an advocate of pins first dovetaiing. He was not known for taking any prisoners when it came down to speed of working, so I doubt any time advantage of doing tails first is worth commenting on. He learned is craft longer ago than my one on these forums, for sure.

Mike.

 

[Jacob]

...It is ludicrous to argue that because it was not seen on old work that we should not, if we feel the need, when the truth is, it wasn't done becuse it couldn't have been.

It wasn't done because it isn't necessary.

 

[Glynne]

Nowhere near as contentious as sharpening but it can still raise blood pressure in certain quarters.

I did warn you! As with sharpening threads, a lot of sensible and differing views and then........the J bomb.

 

[woodbrains]

...It is ludicrous to argue that because it was not seen on old work that we should not, if we feel the need, when the truth is, it wasn't done becuse it couldn't have been.

It wasn't done because it isn't necessary.

Hello,

I wonder if, because women didn't do woodwork back then, they shouldn't now, as everything was done then as it should and we should only do the same? Or perhaps some are more enlightened! We move on, we advance we get better. For example, just because antique furniture shows over cuts at the baseline of dovetails, does it mean we should over cut ours? An exhibition jewellery box with over cut, randomly spaced joints, no blooming way. So what do we do, dogmatically stick to old ways and pretend that their less than perfect joinery is as good it can be? I've some Victorian furniture which is quite high end stuff. It is very good indeed, but sadly the dovetailed drawers, not crudely done by any means, simply would not fly these days. It is just the way it is. So if running a slight rebate gives the step up in accuracy we need, then we should do it. If we don't have to, (as a rule, I don't) then all well and good. I'll tell you where I might do it, a 24 inch deep cabinet with multiple carcase dovetails that show. If I felt I would gain a better register when transferring the 17 or so pins to the tailboard, hell yes I'd spend a minute running a 1mm deep rebate on the tailboard with a router.

Mike.

 

[Jacob]

....just because antique furniture shows over cuts at the baseline of dovetails, does it mean we should over cut ours? An exhibition jewellery box with over cut, randomly spaced joints, no blooming way. .....

Cheap work is over-cut a lot - cleans out the corners in one move - even over-cuts on the sockets of blind DTs helps to some extent.
With top quality work the over-cut will be so close you would hardly notice but they'll be there just touching the line. Basically because it'd be madness not to over-cut otherwise you would have to fiddle about messily cleaning out the corners - you might even talk yourself into buying pairs of opposite skewed chisels! :lol:

I've got another theory for which I've found no evidence except that it works very well, as follows:
The single kerf DTs common on drawer sides are easiest cut if you do 3 cuts, not the usual two plus coping saw. You'd do a perpendicular cut down the centre of the DT pin hole, probably freehand with no marking or measuring and with a tenon saw slightly fatter than the DT saw. Then the two side cuts would be done by dropping the DT saw into the top of the first kerf, over-cutting as necessary.
Then the waste can be removed without a coping saw but just with a fine chisel - as the first kerf has already taken out some waste and cut it in half, the rest drops out easily. Try it. I was really pleased with myself when I discovered this little wangle!

 

[woodbrains]

Hello,

Well done Jacob, you have innovated a method of making a relief cut down the centre of the waste, which, unless I'm very mistaken, was never taught in wood working school by the old guys. If it went done by them, why don't you say that is unnecessary?

Happily, I have been making just that perpendicular relief cut when I dovetail for many years.

Incidentally, my Victorian chest is not cheap work- mahogany case, carved mirror surround and drawers with delicate sides and slips, flame mahogany drawer fronts, 9 of the 13 drawers have nice locks fitted. It would have cost a bomb, yet there are over cuts on the dovetails. Not done for any reason other than speed of production, but absolutely would not fly in a piece now

Mike.

 

[AndyT]

Please guys, spare a thought for the OP. He's a new member of the forum, probably wondering why his question - which is specifically about jigs - has provoked such a reaction.
If you want to discuss dovetails in general, it's easy to start a new thread to do so, but meanwhile, does anyone have anything to add about the use of jigs in thin stock?

 

[deema]

Cutting a rebate for a Dovetail is very simple and quick with hand tools, you don't need a router. The rebate 'trick' is I understand not to aid marking out, but to hide any issues with the base line. As such, any cabinet maker worth their salt would rather avoid the small extra effort and just make dovetails that fit.

If however you are starting out, I would advise on your first pieces that may be on display....usually for the loved one.....that a rebate is used. The inside of the draw is what is seen, and any small gaps in the base line will be visible. A rebate will hide any billy do's!

To dispel a myth, there are no more saw strokes to cut through 1" thick stuff than there are to cut 1/4" thick stuff with the same saw assuming that the gullets of the saw are not overloaded with the spoil. If you use a Dovetail saw with c14tpi you will be fine to gang cut anything your looking to do for cabinet work down to say 1/4". (I.e. Two piece 1/8" or 3mm thick) If you use a saw with a 20 or more TPI, the thickness of the stuff becomes important, not because of the effort involved / number of stokes but because once the gullets become full the saw will not cut straight and will wander.

In my experience people find cutting stuff hard work because they are using a saw with too many teeth for the thickness of the material. The gullets become full and the saw stops cutting and starts to wanders. You make less progress with each stoke of the saw, tend to apply downward oressure to compensate and become frustrated as the saw wanders off line. Most people think it's because the saw is dull, this may be the case, but in most it's because the saw has too many teeth per inch

 

[woodbrains]

Hello,

Sorry, but since the OP seems to have decided to cut dovetails with chisels and saw etc, some tips on doing that did not seem out of order. I didn't mean to divert the thread, apologies.

In my experience, there are not many jigs that do small dovetails in thin stock that actually look reasonable. Gifkins jig was specifically designed for small boxes and looks to be the best, but I don't own one. I do have a Leigh jig which will do thinish stock, but the angle of the dovetail bit gets steeper the smaller you go and IMO look silly when the angle gets too steep. Both these systems are expensive, too.

I suggest the OP should try hand cutting them in the small scale he wants to do. However, it is not impossible to 'jig' sawn dovetails. He might like to find Robert Ingham's book, cutting edge cabinetmaking. There is some useful info on dovetailing for small scale work in that, he might find interesting.

Mike.

 

[Jacob]

...
Happily, I have been making just that perpendicular relief cut when I dovetail for many years. ....

It's slightly more than a "relief" cut.
One perpendicular cut for a single kerf DT, or two cuts defining a wider pin hole, then start the saw in the kerf for the angled sides. Works well with a wider pinhole as the waste is very easy to remove. Much easier than fiddling about with a coping saw. Coping saw is a mistake.

 

[gjhimages]

Thanks to everyone for all the interesting replies, I believe the way forward is to cut by
hand. I have been looking at Paul Sellers website blog and YouTube
Very interesting and thought provoking