Wednesday, 24 August 2016

It Has To Be Perfect

Next stage of the oh-so-secret project.

It's all about dovetails and accuracy.

Do you know that feeling? Your project has to be perfect. At least it has to be perfect enough for you, so that you have got a good conscience. But challenges are waiting for you.
My challenges in this stage of the project are "dovetails". Of course meanwhile I'm able to do them. And often enough they didn't look that bad. So what is the problem?
The most experiences I've got with dovetails done in softwood. If you know the tricks you can achieve reasonable results. But in hardwoods I've done dovetails only two times. The very first time at the drawers for my writing desk. Man, I've worked concentrated and proper but I made every mistake you can make. They are not bad, but have their issues.

My first half blind dovetails at my desk drawers

The second time, I've tried to make a box in Beech. I think I've done that project more than a year ago and it is still not glued up.

Trying out a box in Beech w. gappy DTs

Now then, here is my next try of dovetails in hardwood.

The Tails

After all the watched videos and read articles I've collected some techniques that I would like to try.
The first two things I will check out is to gang saw the tails and to work with a cutting template.
Let's start with the template. This is nothing more than a backer board. I've dimensioned it to fit exactly the width of the tail boards. That makes the alignment much easier.
Next was to lay out the dovetail spacing. I wanted to have three tails and the spacing between  the tails should be 6 mm. That calculated I've laid out the marks on the template board first and as I was satisfied I've transferred it to the tail boards. The template assured that I just could flip over the boards and had the same layout at the opposite end.

Template board

That done I have pre-sawed the tails in the template board straight to my lines.
With all the preparation work done I've ganged up all boards and could saw all tails at each end at the same time with the guidance of my template.

Template with established saw kerfs

Wow, that went well. The saw cuts are looking good so far. Pretty straight, all similar.

All tails sawed

Chopping out the waste was next. That's nothing very special. I've done that as always and have stopped short before my knife line.
After I've chopped out the bulk of the waste I've clamped a straight piece of wood direct to my knife line.
This one should guide me while paring to my line. That ensures squareness and not to overshoot.

Paring block in use

That was a long way to go. Frankly it reads longer than it took. But it was absolutely worth the effort. I have got nice tails with no need to fiddle around and make things worse.

The Pins

Is it called the pin board if we are speaking about half blind dovetails? Anyway, I will use that term in the next paragraph.
Now it comes to the point which I personally find challenging. Creating pins and recesses (in the case of half blinds) which are fitting pretty accurate.
I can't exactly say what went wrong in the past, but the major issue I had was that the joint had slight gaps at the recess ground (tail looked like too short). I guess that greater accuracy might be the key. So I concentrated on this topic.
First of all I've tried out a method I've read about a few times and actually I've seen it in one of the last issues of F&C. Doing your layout on some blue tape.
That said I've stuck a piece of tape on the back face of the board and another one to the edge and made all may layout on this tape.

Transferring the lines from the tail board

Of course I cut deep enough so that I had defined knife lines in the board to pare to.
Then I have removed the tape for the recesses and started to remove all the waste.

Recesses are clearly now

I've drilled out some of the material to ease the process. Then I've chopped out the material and stopped 2-3 mm before my knife lines. Now again I've clamped a straight block of wood directly to my knife line which was my reference for paring the rest of the waste.

Paring horizontal....

...and vertical

Clear recesses

All that done I have removed the tape and checked the recesses with a square. I had still to remove slight humps at the ground of the recess. And now the great moment had come. The connection of both boards.
I've laid them one above the other and in the very first moment I've thought "sh*&". But wait with a tad more pressure it starts to slide into each other. Grabbed the rubber hammer and started to increase the force. And man, watch this. They went together in the very first try, without any correction.
I'm impressed by myself. Of course there have been slight issues. So I took them apart, made some very slight paring cuts and assembled them once again.

First edge jointed

Are they perfect? No they aren't. But way better than I've done before. They will close a bit more when they will be clamped and I believe that the glue will swell them too.

Meanwhile all pins and tails are done and once again I've got some issues. Mostly there are gaps between the tail end and the recess wall. Honestly I don't understand what I have done wrong. But I will wait judging the quality until the glue up. Maybe I'm just to critical with myself.

Stay tuned!


  1. Hi Stefan
    In my opinion, I think that joint turned out very well. The whole reason for using a half blind joint on a drawer is to end up with a very strong joint that leaves a drawer front that shows no sign of a joint when the drawer is shut. When that joint is glued up it will serve its purpose for many years.
    Look at antique furniture in a museum, the dovetails were obviously laid out by eye. They were never perfectly cut, tool marks were left on the piece.
    I think we're used to comparing our work against some machined out piece of work or some "guru of dovetails" we probably saw on youtube.
    The old craftsman we hold in such high regard I doubt ever worried about perfection in an unseen joint. Production was the name of the game, his reward was he got to feed his-self and his family.
    I do woodworking because I enjoy it, I like the challenge and I like making something useful from a piece of wood. I'm no CNC machine tho, sometimes my dovetails come out strong and visually nice and sometimes they look like your gappy beech box. When that happens....I just try again!

    1. Hi Stephen,
      thanks for the encouraging words. I made the same observations like you. Every time I when I had the chance to look at antiques I saw dovetails that are good and strong, but not perfectly looking.
      For sure there is some tolerance if joints are made by hand and one is always impressed by watching these dovetail guru stuff :-).
      This time there is no time for doing it once again because I have a due date and as often I'm behind the pace.
      Maybe I've chosen the wrong joint for this purpose.
      Anyway, they are not bad this time. And I'm glad that I could improve them.

    2. I'm curious to see what the secret project is. It must be something special because it looks like you did everything you could to try and get a perfect dovetail joint.
      One tool I'd like to get for blind dovetails would be a fishtail or dovetail chisel, I have a tendency of tearing up my work trying to cleanout the corners.

  2. Hi Stefan. Your joint looks very good. It looks like there are small gaps near the Roman number II on your tail board, but all other areas are tight. As I read your description I was thinking that the blue tape might cause a small gap at the FRONT edge of the recess (near the widest part of the tails). That's because if you use a marking gauge to scribe the base line on the pin board, the tape holds the gauge off the wood by the thickness of the tape. But that would have the opposite effect of what you got. Interesting.

    1. Hi Matt,
      thanks for the hint. I've tried to adjust that by aligning the boards a tad closer. But maybe that was not close enough.