Another dovetail question . . .

[Jessica Pierce-LaRose]

A couple of the recent threads about dovetails got me thinking about a different question that's kind of bugged me. Often times in magazine articles and such, when dovetails need clamping, you see folks using notched cauls to fit around the proud pins (or pins and end grain bit in half-blinds) during glue up, or they make mention of the cauls being soft enough that they fit deform around the slightly proud pins without a problem.

Do a lot of folks do this? It seems like a lot of work. For some reason I learned to offset my dovetails the other way - setting my marking gauge for the baseline to the thickness of the stock plus a hair (I just slide a business card under the head of my wheel-type gauge) so that when everything joins up, the tail board is a hair proud of the end grain of the pin board. This way, if you need clamps, you don't have that interference. Since I tend to use the shooting board on the end grain (it makes my pencil or knife marks stand out a bit more, and of course helps square things up) or at least plane the end grain prior to marking and cutting, I've already hit it once, so I'm not doing a lot of duplicating of effort. And for inset drawers, since a I already fit my drawer to the type of fit I want by sizing the drawer front, I'm not changing that fit trying to make things flush up perfectly. For folks who don't like layout lines, it removes a lot of them in the sizing.

I honestly have no idea how I learned to do it this way, I'm sure it's just whatever I read first when dovetailing, but I always thought it was the "normal" way. Flipping through another Fine Woodworking article on dovetails, I realized that it may very well not be. Is this face-grain / tail board proud layout less used than the end-grain / pin-board proud method of construction?

[Andrew Hughes]

Hi Joshua,i use cauls sometime esp when i have the face all nicely planed iwould rather make cauls then clean up the whole side again.If i have decide i am going to work the side again the i do leave the pin under the tails.But then one has to be careful when sawing the broken pin corners or the saw jumping may leaves a defect further down below the surface.C or no Andrew

[Chris Griggs]

I think most things do say to keep the end grain of the pin board proud. In fact I can't recall ever seeing an article that says to leave the long grain proud...but funny enough I at some point switched to keeping the long grain proud as well,for all the reasons you mention...(clamping, removing layout lines, predimensioned front....)...well, usually, on drawers anyway. On something like a bigger case I'll often keep the end grain proud because its less to plane down then the entire case side. But I agree there are benefits to leaving the long grain of the tail board proud instead.

[Bob Lang]

It's personal preference, which would you rather plane? Most of the fancy caul suggestions I've seen appear to be a waste of time. If you can tap a dovetail joint together, and it stays together, what is the need for clamping?

Bob Lang

[Winton Applegate]

I think it boils down to this :

1. If a person wants to “peen” the ends of the pins to make the fit look better before the glue has set then leave the pins proud.

2. if a person can cut the joints well and no need to peen the pins then leave the sides/tail board proud and plane it to the drawer front/pin ends.

Why 2 ? so there is positive pressure on the drawer sides to hold the joint tight.

If the joint fits quite snug like Frank Klausz demonstrates then no clamps are required and put the drawer bottom in to square up the joints and DONE.

I am not so sure I would go a full business card thickness. Perhaps one layer of typing paper, three thousandth of an inch, for the gauge off set.

[John T Barker]

Personally I learned to clamp a dovetailed drawer or case (or whatever else) and I never used cauls to fit between the pins nor did any of my co-workers. The shop I trained in (Irion Company) is pretty much a good place to learn, as far as I know. I've never heard of woodworkers peening their dovetails, does this go on much?

[Winton Applegate]

Here (http://www.woodworkforums.com/showthread.php?t=86111) they call it “Bishoping” (or apparently Roy Underhill does).
Some where I read it as “Killing” the pin. I could not find my source. Yet.

[Jim Matthews]

I've seen it done with Pine boxes, and suppose it will work on other soft woods.
It's more effective with thicknesses greater than 1/2" as it's effectively spreading the end grain.

I aim for slight compression when joining dovetails, and if they don't fit after the glue up
I'm more inclined to slip in an endgrain wedge than hit any box I managed to make with a hammer.

Our very own Derek Cohen has a demonstration ITW - here (http://www.inthewoodshop.com/furniture/PeeningDovetailsinWood.html).

Given his skill set is far in advance of mine, I'll stick with wedges after glue up.

[Pat Barry]

I aim for slight compression when joining dovetails,
I'm sorry - what do you mean that you aim for a slight compression? How do you get compression? Do you mean the dovetail joints have to be pounded home? Is that with glue applied or without? Can you clarify this Jim?

[Jim Matthews]

Just as you mention, I need to "persuade" the sides closed.

I use a metal hammer, as I was taught.
I can hear the sound of a solid blow.

It sort of "rings" if it's coming home.
It sounds dead, if it's too tight.

I use Old Brown Glue, so the feel of a joint coming together is consistent.
It sort of steps into place, if I've fitted things well.

I check each pin and tail for square with a small metal rule as an aide to alignment.
(Thanks, Phil Lowe - money well spent.)

Chris Schwarz details the method of checking before glue up that I use
with a small rule, but any straight edge will do.

http://www.popularwoodworking.com/techniques/joinery/defective-dovetail-diagnosis

I make my drawers slightly wider than the opening, and plane to fit.
I can clean up the surface, if hammering leaves marks.

I'm more successful cutting dovetails in softwoods than harder woods.
If I'm using different species, I try to make the pins out of the harder stuff.

I'm NOT the best source for technical advice on dovetails.
There are more experienced and capable posters.

This is just what works for me.

[Pat Barry]

Jim, I imagine you still do a dry fit first before gluing, right? It seems that would be rather difficult to do with them fitting so tight as you describe. I would worry about breaking the edges of the joints doing the dry fit, then knocking them apart to ready them for glue.

[Brian Holcombe]

I keep some veneer handy for any of the woods I use regularly. I use this ahead of peening. I use peening to fill small gaps.

i've been needing it less and less as I continue to do everything by hand, but it doesn't hurt to be prepared.

Also, on dovetails my end grain is always proud, and I've thought it a product of compression. I welcome it as I like to cut the end grain after.

[Jim Matthews]

They're snug enough that I can get them in about 1/2 way by hand.

That's when I inspect for tight spots to pare down.
The Old Brown Glue is slippery when properly warmed
and the pieces tap together without much resistance.

I can hear it "ringing" when the fit is right.
Excessively tight joints sound dull, like a punching bag.

I relieve the inside edge of each tail so that it assembles readily.
I can't recall who showed me that, so I'll presume it was Phil Lowe.

It's a slight chamfer made with a chisel so that the edges don't "catch" when I'm starting out.