Wednesday, March 11, 2015

How I Clinch Nails - A Photo Essay

Here is what I want.
There are lots of ways to clinch nails.  I like this method because it is quick, and requires nothing special besides a hammer.  

The first time I heard of clinched nails was during the episode of the Woodwright's Shop when guest Christopher Schwarz was discussing his book, "The Joiner and Cabinet Maker." During this episode, Chris made a shipping crate with clinched nails for joinery.

Clinched nails are great because they are quick to do, require no glue (so no drying time), and are amazingly strong.  Also, they make a great joint for a cross-grain batten as while the wood contracts and expands, the nails can give just enough to keep everything nicely together and flat.

There are a couple things that are not shown in this photo essay.  My cabinet door is soft spruce, which is less than ideal.  I figure if clinching nails works with spruce it will work anywhere.

The ship lapped panels I am using are 18mm, the crossbraces are 28mm (3/4" and 1 1/8" or so).  I wanted nails that were at least 2cm longer than the thickness of all the wood.  I bought some regular unplated brad nails at the home center that were 80mm long for this.   Brad nails in order that they could be countersunk.  This panel will be painted, so a little putty and the nail hole on the face of the cabinet should disappear.  I think practically any wire nail should work.

The first thing I did, which is optional depending on how the piece needs to look, is I drilled pilot holes for everything.  As this is a piece of furniture, I wanted to minimize blowout and cracking.  If you are making something like a shipping crate, going straight to nails should work just fine.  If it matters, spend a little time laying out where the nails will go for strength and beauty.  I drilled holes that were significantly smaller in diameter than the nails, so there would be a tight fit.  I don't want them too loose, as brads could be pulled all the way through.
While I used a bradawl on the crossbraces, I used my hand drill for the panels.
With the pilot holes drilled, I insert the nails so they just poke through.
Notice I already painted the rabbets for the ship lap.  I won't get a chance to paint that later.

This lets me line up the cross brace into the pilot holes I already drilled.

Here are all the nail tips just poking through.

I found it easier to line up the holes for the battens on one board at a time.

Now it is time to flip the piece over.  I have the batten resting on the edge of the bench, but the nails are hanging over so I don't put nail holes in my bench.

Pound the nail down about half way, so there is still plenty sticking out.  I used this woodblock as a rough guide, so I could drive all of the nails about the same distance in.

With the nail sticking half way out the back, bend all the nails over. 

Now I am bending them over as far as they will go.

Flip over again, and drive the nails as flush as you can get with the hammer only.  No need to set these yet.  Once again, this step and the previous ones are done with the piece halfway on the bench.
Flip it over again to show the bent nails.  I have no idea why this happens, but some of your nails will be pointed in wonky directions.  Not to worry: just twist them into a straight line with your fingers.
It's OK to twist these straight again.

Now I use the hammer again to bend the nails a bit more, so they are pointing down.

Now you can set the nails.  The previous step might have pushed them out a bit, so make sure they are all the way in as far as you want now.

Here is what my panel looks like at this point.

Using an angled blow with the hammer, try to bend the nail over where the tip will re-enter the wood.

Like this.

Super-duper slo-mo.

Take your time and pound it in just where you want it.

Even more.  Is this level of detail perhaps a bit unnecessary?

The last blow.  Notice that in soft wood like this the nail is now set below the level of the wood.  I like this, but this doesn't happen with some of the harder woods.

I didn't notice until it was too late that the nail cracked this board on the end.  There was not enough wood to support it.  On the next door, I cut the nail a little shorter, and drilled a pilot hole where the nail tip re-enters the wood and there was no crack.

The completed door.  I feel like this will never come apart.
This method works great.  Especially if it isn't critically important what the clinched part of the nail looks like.  While not everyone may like it, I am fine with the way this looks on the inside of this cabinet door. 

I think that if you want the clinched part of the nail to be as short as possible, you might try a different method which involves driving the nail through the wood into a steel plate.  I haven't had such good luck with that method, as I have yet to figure out how to steer which way the nail will bend.  This way, I feel is dummy proof.  Anyone should be able to get the nails in a relatively straight line.


  1. hi Brian, very interesting indeed, will be quite useful for building simple boxes or mock ups. I first saw this on the english woodworker blog. Thank you.

    1. Interesting you should say that. My method is very similar to that one. Probably because I really got comfortable with this when building Richard McGuire'a travelling toolbox.

  2. I've never done this involved method for clinching nails, but I'm sure they will function admirably. I put up a treated fence several years ago and clenched all the picket boards and they are all still tight despite being a lot drier now. Due to the rougher nature (and that I had hundreds to do) I drove the nail in at 10-15° against a steel plate, didn't control the exit wound appearance, but got the job done.

    1. Perhaps it looks involved, but it's not. The only thing that all of the pilot holes do is control blowout a bit, and of course laying out the nail holes makes things prettiers. If I was to do a fence, I wouldn't worry about any of that, either. However, I've never quite got the hang of the steel plate method.

  3. Clinches boards and cup hinges - 18th century meets 21st century ! I like this pragmatic approach.
    A lot of woodworker think nailing is outdated, but properly used it is so fast and cheap in material but still very durable. Great article!

    1. Haha, you noticed that. I'm not so happy with the hinges on this project. The short grain between the end of the board and where I drilled with the Forstner bit blew out, so I have to fix it. I suppose I should have expected that. Also, I had difficulty hanging them after I already had the back of the cabinet nailed on. I have to go in and adjust the hole I drilled, as the hinge doesn't adjust that far. I feel butt hinges would have worked better in this case.

      However, I have no problem whatsoever in using whatever construction techniques from whenever on a cabinet like this. The nails were quick and easy for this mockup. I think when I make the final one, it will be with solid wood and proper case joinery. This nailed mockup, I feel, is just as strong if not moreso than the knock down joinery of the original.