# Dovetail: half-pins or half-tails on the edge?



## Sylvain (Jul 23, 2011)

After reading this wonderful site for about one year and a half, I just realised two days ago that 99% of dovetail joints have half-pins on the edge of the assembly.

A few have half-tails on the edge and some, probably done with a jig, have one half-pin on one side and one half-tail on the other.

So I went again trough a few demos, nobody draws ones attention to this (common) practice.

My questions are: 
- is the common practice the best practice (I guess yes) but then

- why?


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## JJohnston (May 22, 2009)

About the only reason I can think of is when you open a drawer and look down at the top edges of the front & sides, if you have a half pin, the front looks like it goes all the way to the corner, but if you had a half tail, the side would.

Here's a Roy Underhill episode where he looks at an old tool chest with the dovetails done "backwards".


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## teejk (Jan 19, 2011)

one consideration…I you plan to dado a drawer bottom, plan your layout accordingly unless you want stopped dados. I like to run the drawer dados on the TS and want the exit point on the fronts if a drawer front will hide them.


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## Sylvain (Jul 23, 2011)

Thank you for the answers.

I can see the benefit of half blind dovetail with half pins for drawers.

The Roy Underhill video is entertaining but he seems to say that common practice is just tradition without justification.


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## Smitty_Cabinetshop (Mar 26, 2011)

Sylvain,

As J mentions above, Roy had an episode where ge discussed standard practices. He disn't say what it's standard, though. I saw that wpisode on the web while I was working om my roubo bench cabinet, so I put some variation in the drawers. 










Why? Just to have some fun. I know which look I prefer. How avout you?


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## Sylvain (Jul 23, 2011)

Smitty
Thank you for your comment.
It didn't catch my attention at that time, when I saw your episode 16.

Any user who is not a woodworker would not be interested in seeing the joint and it shouldn't show when closed;
A fully blind dovetail would be overkill for a drawer but nice for a jewellery box.
I would be surprised when first opening your bottom drawers.

When opening the drawer, the average user is probably more interested by the inside appearance. [especially our better half putting some silk stuff in it]
(added benefit of the rabett you mentioned in your skill post)

But what about other uses than drawers, e.g. for a chest or box?

Your bench cabinet frame (episode 7) is something different than a (simple) box, you have half-pin + half-tail cut at 45° for the apearance in the front and back view.

I will revisit your different (very informative) blogs and have another closer look.


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## Loren (May 30, 2008)

Pins are tougher. Tails have short grain where they are angled
and can shear off. You'll see this sometimes in old pieces with
through dovetails. For drawers it probably doesn't matter but
my understanding of tradition is that pins were preferred on the
outside.


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## Smitty_Cabinetshop (Mar 26, 2011)

"I would be surprised when first opening your bottom drawers."

You know, the surprise may be that there's dovetail vs. rabbet joinery in the drawer's construction. Which may be why half pins are used: to more readily call attention to 'quality' construction. But that's likely a bunch of hooey… I have no idea.  And Loren's 'short grain' observation makes alot of sense.

I'm glad to hear you read about the mitred dovetails on the carcase of said cabinet. That was a fun build!


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## Sylvain (Jul 23, 2011)

Although they may shear, I understand tails are on the side of the drawer because the joint has to withstand the traction each time the drawer is pulled open; in particular if the glue has failed.
(In antique furniture, build when there was no central heating, hide glue may fail due to lack of humidity and excessive shrinking of the wood) A rabbet is relying on glue only.

Drawers are sometime jammed.
Build the other way around it would unplug under traction and one would be left with just the drawer face in the hand.

Smitty, if I am not wrong, the picture 19 in the episode 3 of the "tool chest refurb" shows a pin which had failed. But it seems to be the bottom right board in picture 20 of episode 2. So it is not at the edge of the panel and it is not totally relevant to my initial quest. But it shows that pins may also fail.


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## Sylvain (Jul 23, 2011)

I am currently looking in various books on the excellent site

http://www.evenfallstudios.com/woodworks_library/woodworks_library.html#Hand%20Tools

In the following book, 
Bench Work In Wood
A Course of Study and Practice
by W.F.M. Goss, 1890
http://www.evenfallstudios.com/woodworks_library/bench_work_in_wood.pdf

All the exercises about dovetail assembly including the "Lap or Drawer dovetail" used by Smitty for its large drawers herebove and the blind dovetail are done with half-tails on the edge.
see page 111 to 117 (119 to 125 in the PDF)
There is not any one exercise with half-pins at the edges.


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## bhog (Jan 13, 2011)

Here is a picture taken from a "woodworking glossary" in the back of a series of books titled "Build it better yourself.Woodworking projects" This one was published in 1989.I looked at these books alot in my younger days.I have done them both ways and have always felt that the way pictured was stronger.Especially when there is a drawer front screwed to the pin board.


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