Blind Dovetail Tips by Tim Rousseau
One of the problems of getting old is that you have a harder and harder time knowing whether you’re seeing a new technique or simply one you’ve forgotten. I find myself in that position as I write this post. Tim Rousseau, by way of Lie-Nielsen, is talking about creating blind dovetails. It’s not your average ‘here’s how to do it’ video. Rather, Tim is providing some tips to get them done quickly and effectively and assumes you know the basics of dovetailing. I found a couple of his ideas ‘new’ to me so I thought them worth replicating here. Lie-Nielsen has a lot of great videos on YouTube and if you haven’t watched them, I encourage you to do so.
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Cheers — Larry
Q&A: Why Do You Joint Boards In Pairs?
This is a post is a response to a couple queries. Both came from people who had read someone who talked about jointing two boards, by hand, in preparation for joining them into a panel. They wanted to know what that meant and why one would do it.
Back when I started the vanity project I’ve been chattering about I started by cutting a bunch of parts from red oak. I decided that I preferred to build those cabinets using cherry and so I was left with a bunch of oak pieces. I used a couple pieces to create a simple bench hook that I use when planing small pieces. I’ve kept a couple similar pieces with the thought of creating a new bench hook for cross-cutting small pieces. The one I’m currently using is made from pine and it works great but is a bit worse for wear.
Opportunist am me as I can use this small project to show jointing in pairs. It has the advantage in that the two boards don’t match well in terms of grain which is fine for a shop appliance and even better for making it easy for you to see the darn joint I’m trying to illustrate in the photos.
Jointing in pairs is exactly what it sounds like. You square up and flatten two boards with the two boards clamped together.
Jointing requires two results to be successful. The first is that the boards be flat lengthwise so when their edges, when pressed together, form a good joint. Secondarily, but no less important, they must be square across the edge so that the joint comes together across the entire edge surface.
The logic of jointing simultaneously is simple. It doesn’t help in getting the boards flat along their length. But consider a case where you joint two boards individually and you manage to plane one at 90-degrees but the other one is planed at 89.5 degrees across the width of its edge. The joint will be great on one side but there will be a slight gap on the other. No joy will be had when you glue them together.
But what if there is a slight error in the angle across the face when you’re jointing both boards at once? I’ve tried to draw an exaggerated error so you can see how this approach negates the problem completely.
This shows two boards, jointed simultaneously, but drinking was involved and the angle across the face is somewhere around 85 degrees.
When the two boards are rotated upward relative to this position to form the joint, however, you have one board whose edge is 95-degrees while the other one is at 85-degrees and are these complimentary angles form a perfect joint.
When you do the glue up you can confident that they will create a nice panel.
In this case I’ve made a bench hook that I don’t want to be smooth as I would in when doing cabinetry. I don’t want this bench hook to be slippery and, in fact, I’ve sanded it with 60-grit paper to roughen it slightly. So, overlook the less than glass finish; it’s intentional 
Cheers — Larry
Lateral Thinking Comes to Dovetail Practice
I just had to post a link to this YouTube video, which was brought to my attention by the Pop Woodworking blog. It’s one of the funniest takes on joinery I’ve ever seen. My only criticism? They didn’t drawbore the mortise & tenon joint.
Cheers — Larry
The Importance of Marking the Show Face
It’s been a week since I’ve written anything here. Sometimes these pauses are because I’m off doing non-woodworking stuff and have nothing to show you or talk about. This time the problem is that what I’m doing is, well, err…it’s just plain boring.
You see, I have these Adirondack chairs. They need paint. Painting them by hand is a pain in the butt. Too many cracks – too many edges. To make matters worse, we got rain just as I was planning on taking them into the backyard for a marathon painting session. And so it’s been a slogging good time, painting, waiting to dry, flipping chair over, waiting to dry…etc., etc.
In my small shop this really ties up the limited real estate. I’ve shot these quick shots to show some of that congestion. You can see that I’m holding my table saw down with a drop cloth and chair. I call this my paint studio. I’m marking the path into/around the shop with light blue chairs. This gives me a 12″ wide walkway into the shop. How much more do you need, after all? And, my saw bench and shop bents are holding my vanity cabinets, who patiently await their mirror faces, which are laying on my router table. And as there’s usually some wet paint in the shop, making a lot of dust isn’t something I can do even if I could.
But you know how it is if you haven’t cut wood in a while. You get itchy fingers. You need to do SOMETHING. And this is where working with hand tools is so accommodating. Just “playing” with hand tools is ok, even useful as helps to hone one’s skills. I’ve never used a power tool just to have fun.
And so it was, as I stood in the mess I decided to cut a set of dovetails. I grabbed some scrap, drew a line down the middle of it, and cut it with a handsaw. I quickly marked out a couple tails and cut/chopped them. I marked the pins from those tails and cut/chopped those as well. Then I tried to put them together. They didn’t fit at all.
And it turns out, I created an example of something I avoid… normally, and being a blogger I thought it an opportunity to show you the reason why you need to mark the show faces of every part you’re working on. I did a post called Marking Reference Faces that shows how I use blue tape to do this, but I didn’t do it with this practice set of dovetails – it was just practice.
The reason my dovetails didn’t fit together was that I hadn’t marked the faces that would form the outside of the joint corner. When I marked the pins I oriented the tail piece such that the show face was on the inside of the joint, not on the outside. Thus, when I oriented the boards properly, the pins were backwards to how they needed to be. I flipped the tail board around and everything fit together nice and tight.
But there was a problem. When I cut dovetails I’m very concerned about the saw cuts on the show face but I’ll often cut just beyond the line on the inside face. It barely shows on the inside of the joint and, in fact, it’s an indication that the dovetails are hand-cut. Because of my error, those cuts beyond the line are on the outside of the joint and quite visible. Interpretation: high yuck factor. But if you’ve got lemons, make lemonade and thus I present this lesson on the importance of marking your show faces.
Cheers — Larry
Revisiting Dowel Joints
There are various points in a project that excite, scare and even provide relief. I always get excited when I get an idea to the point of cutting wood. Between this point and the glue up, for me, is the real “fun” stuff of woodworking and my emotions run more along the lines of “kewl” and “this is so relaxing.” I just like to feel and see wood change from flat stuff into useful, or even whimsical pieces.
But as I approach the time to glue up a carcase I always get scared. Not Stephen King scared – more like the “about to give a speech” kind of scared. As an aside, I’ve tried imagining the piece I’m going to assemble in its underwear. It doesn’t work. At this point in the project I run everything I’ve done through my mind. Did I square every edge properly. Is the joinery ready for assembly? Is the glue fresh? Do I have enough clamps. Any chance the UPS guy is going to show up? What have I forgotten?
And just as there is this anticipation, once the glue up is done and the piece comes up square, there is relief. There’s still a lot of work to do at this point but, for me, it’s all downhill from the glue up stage. It’s back to the fun stuff.
And that’s where I’m at with my vanity project. The glue up went smoothly, though I managed a fat hide glue thumb print on one of the cabinet sides everything is as it should be. A bit of glue squeeze out to deal with but that’s a minor issue. It’s door fitting time.
Dowel joints
But I’m writing this for another reason. I’ve just had an email dialog initiated by a question about how “loose dowels rattling around in holes” could provide a good joint. At least that was the start point. I realized after this discussion that possibly the reason so many think doweled joints aren’t strong is that they aren’t doing them correctly. What was clear from this discussion is that at least some are compromising precise fit to get their dowel joints to fit together.
I’m probably going to get myself in trouble for saying so but I believe doweled joints must be done as accurately as mortise/tenon and even dovetail joints, though there are cosmetic goals with dovetails that aren’t required for doweled joints. But if you’re creating a carcase where the dovetails will be covered by mouldings, there is more room for error in those dovetails than in proper dowel joints.
If you look at a doweled joint it is essentially a butt joint of end grain to long grain without the dowels. Nobody would consider this to be strong enough for a cabinet. Thus, the strength of the joint comes from the surface area provided between the dowels and the holes in the two cabinet pieces. If those surfaces aren’t tight, you lose.
It is simply not an option to drill the holes larger than the dowels so that it’s easy to fit the joint together. The only way to do these joints properly is to 1) use a significant number of dowels, 2) drill the holes in both mating pieces very accurately, and 3) ensure that the dowels fit in the holes sufficiently tight that you have to at least pound the joint together with your hand.
I showed how I made a jig and drilled the holes for my vanity cabinets and how I used it to drill accurate sets of holes. Unfortunately, I didn’t include any other details about doing dowel joints. My bad, and now I have no photos to show of the assembly process. Maybe a description will be sufficient. Hope so.
For these cabinets, which are small (14″ x 24 x 4 1/2″) I used 5 dowels per joint. These were 5/16″ x 1 1/2″ fluted dowels which are actually just a smidge (I think this is metric ) larger than 5/16″ and they fit a 5/16″ hole tight enough that if I put one in a hole, it’s difficult to pull it out.
To do the actual glue up, I glue the dowels into the side pieces and let the glue set up. Then I do a dry assembly just to ensure that everything is going to fit properly. I use a rubber mallet and/or the palm of my hand to persuade the pieces together and get them apart again. Then, and only then, do I add glue and clamp things up, checking the case for square as with any glue up. I use liquid hide glue for this as it gives me a longer open time than hot hide glue.
I hope this helps a bit. I’m sorry I don’t have photos of this process but James Krenov’s The Fine Art of Cabinetmaking, a book that every woodworker should own, has a good set of photographs of the process.
And while the glue dries…
Oh, and while the glue was drying I made this planing bench hook, modeled after one described in Tom Fidgen‘s Made By Hand book. Have I mentioned lately that I like this book? It’s one of the best books available on using hand tools to build furniture.
Those who follow the blog might remember that I first bought a bunch of red oak for my current cabinet project. It was just not satisfactory and I switched to cherry. This left me with a bunch of red oak vanity parts. I took a couple top/bottom pieces, jointed them as a pair, using my trusty #7, and glued up the panel. The rest came from my scrap box.
And I’ve learned something – I think. Until a year ago, my bench appliances were all made from pine or plywood. I decided to “upgrade” and these were replaced by equivalents made from hard maple. I’ve never liked the result because the maple is just too slippery, which isn’t great if the goal is holding parts while you work on them. And so my most-often used bench device has been a quickly-assembled bench hook for small cross-cuts and made from pine scraps. It works great but it’s UGLY.
I think red oak might be a fine compromise and I think I’ll build a replacement for my other bench appliances too. I oiled the new plane hook but otherwise left its surface “oaky”, so you can feel the open grain of the wood. I think this will hold wood just as well as pine and yet be more durable. Maybe I’m kidding myself but maybe not.
Cheers — Larry
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