Hand-cut dovetail issues

[Mike Brady]

Results using blue tape:

Pencilled the layout on this box.  I always cut the tails first.

[TraditionalToolworks]

Mike,

Those look great, not sure what the blue tape is about, never used that...how does that help you stick to your line?

For me, I don't care if someone cuts with the saw between their legs, if they can hold the line that is what counts.

Results using blue tape:

Can you explain this blue tape? I'd like to understand it. The results look dandy.

One thing I find good to practice is to cut the tails at random, you don't need to do any layout, but then get a clean mark onto your pin board.

You will find you can move the angles around, even on two sides of a single tail, but that if you mark out pin from it, and you cut it correctly, you will have a great looking and tight joint. I use the plane trick that Cosman shows, I think it applies pressure to help keep the tail board still and not move.

One not need worry about how long it takes you, what matters is that you do it correctly and continue to practice it correctly so that you will get better at doing it correctly.


Alan

[Mike Brady]

I tried using the blue masking tape after reading about it here a few years ago.  I wanted a way to clearly indicate where the cut line needs to be once the pin profile is transferred.  Normally I pencil that profile, remembering that the pencil line is entirely in the in the waste area.  I sometimes knife the profile instead of tracing it if the pins are narrow.  With tape, you cover the end grain with the tape and carefully use a sharp double bevel knife (I don't like spear points) to trace the tail profiles while cutting through the tape.  When you peel away the tape covering the tail profiles you have a waste area that is well defined for sawing the tail sockets.  You can read more about this method on Derek Cohen's web pages.  My feeling is that paring with a chisel should be minimal if you learn to saw to a line, no matter how you make that line.

[Jim Waldron]

Derek Cohen has said - more than once, I believe - that the blue tape technique is nice for beginners to provide a stronger visual image for the saw cut. As a bit of facility is gained, a marking knife is quicker and just as good. When saw technique is practiced well, straight, plumb cuts are easy and extra aids are not needed (except for the occasional hasty, messy cuts we all make when rushing the effort). Once you can saw beside or leaving half a line and make the cut plumb, dovetails are pretty straight forward.

And it's good to remember that a lot of museum pieces show that those giants whose shoulders we stand upon made some rather untidy dovetail joints at times that survived a couple of hundred years. Don't get your panties in a twist and you'll be okay.

[KingwoodFan1989]

Hmmmm...that blue tape method looks interesting. The one I've been using that has worked pretty well so far is similar to this one I saw Rob Cosman use a while back:




Unfortunately, upon viewing this video again for the first time in a while just now, I saw a major difference in my approach that could offset the accuracy of the method: He doesn't cut out the waste on the tail board before marking the pin board. This allows for the marking tool (in this case, his dovetail saw) to be perfectly accurate to where the tail is. I've been cutting the waste out and using a marking knife, which can sometimes be off by a few thousandths too many and make the joint too tight. I'll remember to do it his way exactly for next time. I also use feeler gauges for the offsetting rather than a spare piece of saw blade material. I also like to use a feeler gauge that's a thousandth thinner than the saw blade. That way I get a tiny bit of extra breathing room when fitting the joint and also for when the glue is added.

In any case, though, I'm getting better cuts now, so thanks to those of you who suggested not pushing down on the saw while cutting! That definitely helped!

[TraditionalToolworks]

My feeling is that paring with a chisel should be minimal if you learn to saw to a line, no matter how you make that line.

I agree, and that is true of sawing in general, even if you make a mistake it's always fixable. The larger the work the more noticeable when you do make a mistake. I don't rely on my baseline with my saw, I use a fret saw like Cosman had always advocated, and I try to get close, but chop out to the baseline. Maybe the blue tape helps you with that part.

The one I've been using that has worked pretty well so far is similar to this one I saw Rob Cosman use a while back:

I pretty much learned how to cut dovetails watching Rob Cosman's first 2 dovetail videos. I just watched that, and I have actually done that before, and i just saw that Joyce encyclopedia book when I was cleaning up my books recently. Kevin Drake used to sell a marking knife that didn't have any kerf so you could use it in the saw cut like Cosman uses his saw for. That trick using your saw has been around for a long time.

The one thing I always liked about Cosman is how he approaches everything, but especially sawing with confidence. I like in that video when he says, "Now choke up on the chisel just in case there's an accident, it wont' be so bad...". That's kind of funny...

I use 2 sets of dividers like Cosman shows, that is also in the Joyce book if I'm not mistaken.

I use mostly hardwoods for any cabinetry type work. You need to watch and cut to your line, split 'em if you can. You still need to be assured that your tails were cut plumb if you rely on them being plumb...Doesn't take most people too long to get the hang of it. I can't see doing cabinetry work without using hand cut joinery.

Alan

[Greg Jones]

That's an old video from Cosman, when he was first experimenting with that concept. As far as I know, he has stuck with it, even sells a replacement toothed blade for his marking knife that is identical to the blade thickness and teeth set of his dovetail saws.

[Tony Z]

What helped me was doing the PWW/Swartz "30 days of dovetailing". The article first appeared 12 - 15 years ago, advocated doing a set of dovetails each day for a month. Next day, you study the previous day's work and do another set. All in all, the method forces you in practice, practice, practice!

Worked for me, and just in the past six months, I tossed all those practice sets. In the first weeks, I concentrated on my through DTs and by the end of the month, my half-blind.

As far as reading materials, I would suggest Ian Kirby's "The Complete Dovetail".

With regards to Derek Cohen's "blue tape" method, Derek states very early the the tape establishes a tactile & visual baseline, that also helps in laying out pins, by giving a firm baseline to locate piece against piece, much as a slight rabbet would also do. He gous further, that with experience, some will drop the rabbet or tape methods. For me I use neither, but do use a Moxon vise atop my bench, to raise the work, which helps immeasurably with ability to see, mark & saw accurately.

[bandit571]

Hmmm...I seem to do Dovetails way different from what all of you do...
 

   
I lay out Pins first.....Board is clamped high in the vise to do the layouts..

   
Then lowered to almost the top of the vise, and sawn.   Yes, that IS my "dovetail" saw.    I can work this low, because I am sitting down on the shop stool.

   
I clamp the board flat, chop down 1/2 way, flip the board over, and then remove the waste.    I can also pare as needed, and I am still sitting down.
 

Once the pins are done, I use them to lay out the tails. I can stand the pin board up, or use a couple corner clamps to hold things still.  Just a sharp  pencil is used.   I merely try to leave the lines by cutting on the well marked waste side..

   
Bandsaw usually, since it was down at this time, I used the old No. 4 again...added a few extra cuts in the middle of the waste, makes it easier to chop.   Then a test fit..
 

   
And pare as needed.  
 Just the way it seems to work for me....YMMV

[Mike Brady]

There are several valid ways of laying out and cutting dovetails , as shown in this thread.  I have several friends who believe strongly in the magnetic sawing guides available from sources like David Barron or Lee Valley.  Some have even made their own guides.  I hesitate to be critical of any method that gets you a the benefits of a real dovetail.  I am in a club of over a hundred woodworkers.  Withing that group are about 25 hand tool enthusiasts.  Of those, maybe a handful can make a decent dovetailed corner.