Building an Outdoor Table (Part 3)

In this post, we are going to wrap up this project; I'll talk about the joinery I used, and why and then get into the finish for this outdoor table, and why. To recap, in Part 1 of this series, I went through the table design and the wood I selected for this project, which is white oak. In Part 2 I focused on milling the wood and prepping the individual pieces for the joinery. I also covered the layout of the pieces to try and orient them the best way possible to give the greatest visual appeal. In this post, we are put it all together and get it to its final resting place.

Joinery - Drawboring

As with any table, the obvious choice for the apron to leg joint is a mortise and tenon joint. It is a strong joint and has been used for centuries because of its durability and strength. So, when I was planning this table design, I knew I was going to use a mortise and tenon joint, but I also decided to take it one step further and add a drawbore to the joint. I covered what a drawbore joint is, and how to make one in this post so I suggest you hop over and take a look to get more of the details.

In order to make this joint, I had to use my drill press to drill out the bulk of the material; these legs were too tall for my mortising machine, which was a disappointment and I may have to address later on down the road. As you can see in the photo below, once the mortises were rough drilled out, I had to finish the joint by hand with a mallet and chisel. 

One thing I should mention is, I had already cut the tenons and used the tenons to layout the mortises. You can see the layout lines in the above photo. Once the mortise and tenon joints were done, I dry fit everything everything to get a feel for what the table would look like.

It was at this point in the process that I also noted that the table looked too boxy and needed some help. What I decided to do was to put a very slight taper on the two inside faces of the legs, meaning, the side where the table rails are. However, I wouldn't cut those tapers until I have the drawbores done. Below you can see the table base completely assembled and you can also see the slight taper I put on the legs; nothing too much, but just enough to give it a little something.

Once this glue dries, I just need to trim the dowels from the drawbore pegs and finish sand.

Outdoor Finish

You can go back to Part 1 of this build and read why I chose white oak for this project, but since this table is going to be outdoors, year around, I wanted to select a highly durable finish. So, I did some research on this and there are a number of finishes that you can use for outdoors, of course there are. But many of them require near constant attention and refinishing annually; I didn't want that. So, I drew upon my boating hobby, as I did in selecting white oak (boats used to be, and are still, made from white oak) and I decided to go with Epifanes clear varnish finish. Epifanes is used in the boating industry to be a sealer for wood on boats, to protect it from the water and sun, which is exactly what  I wanted with this table. 

The application of Epifanes is kind of a hurry up and wait process. You thin the product out 50/50, apply, then let dry for about 24 hours. Then you thin less and less as you build up the coats. In all, this table has 5 coats of Epifanes on it. This Epifanes finish should last a few years before needing to be recoated. The nice thing about it is, you just need to give the piece a light sanding, then apply a couple more coats and then you should be good for a few more years. So, here is the finished table in its final resting place and ready for years of use.

That is all for now. I have a few other things in the works, and possibly a big announcement in the not too distant future so stay tuned!

Drawbore, not so boring!

For my next project, which is going to be a big outdoor table, I've decided to try something new; drawboring. I've wanted to try this for quite some time now and I'm finally biting the bullet and going for it.

What is Drawboring?

Drawboring is done in a mortise and tenon joint and is similar to a pegged mortise and tenon joint, but instead of simply drilling a hole through the mortise and tenon, and inserting a peg, the hole drilled in the tenon is offset by about a 1/16 of an inch. This is done so that, when the peg is hammered through the joint, it draws the joint together very firm and creates a very strong mechanical joint. In fact, some people don't even use glue with a drawbore joint because it is so strong, but I think glue is still a great idea, you know, just in case.

What do I need?

In order to create a drawbore joint, you don't necessarily need anything special, but I will recommend getting getting a set of drawbore pins. I ordered a 3/8" pin from Lee Valley to match the size of the drawbore pegs, or dowels, I am going to use. A drawbore pin is a tapered piece of smooth steel that, once you have the joint prepared, you push the drawbore pin into the joint to "loosen" the joint a bit so the peg or dowel will be able to make its way into the joint without completely breaking the peg.

How to?

So, how do you make a drawbore joint? Christopher Schwarz has a really good article on drawbores that I suggest you check out for some great details. If you are, like me, more of a visual person, Paul Sellers has a good YouTube video on his channel. There are several others that have examples of how to make a drawbore joint as well.

The basic premise of the drawbore is actually pretty simple. First, make a standard mortise and tenon join, nice clean joint, firm fit, etc. Next, disassemble the joint and drill a 1/4" or 3/8" hole through the side of your mortise joint. I suggest clamping a scrap piece to the back of the mortise so you don't have a blowout on the back side; always start drilling on the show side so it stays nice and clean.

Next, put the joint back together and insert a brad point drill bit the same size as the hole you drilled. I prefer a brad point because it has a nice sharp tip on it that will give you a crisp center mark. Insert the bit into the hole that was drilled in the mortise and give it a light tap to make a mark on the tenon. Do this for all joints.

Once you have done that, take the joint back apart and locate that tick mark you just made. Now, make another tick mark about 1/16" towards the shoulder of the tenon; that is key. If you go the wrong way, you will actually loosen your joint. Next, drill a hole through the tenon on that mark closest to the tenon shoulder. Once all those are drilled, reassemble the joint and use your drawbore pin and carefully push it into the joint to make way for the peg, then remove the pin.

The last thing to do is to take your peg or dowel and taper one end of it so that it can get into the joint without getting hung up. Put glue on your mortise and tenon joint, put some glue on the tapered end of your peg, and carefully drive the peg into the hole until it comes out the backside of the joint. You now have both a mechanical and a chemical bond in your joint with virtually no way to get it apart and should last a lifetime.

Final Thoughts...

So, that is the quick and dirty of the drawbore joint, I will provide a little more visual elements when I get to make the joints for this table. In the meantime, check out the resources above or just do a Google search for "drawbore joint" and you will get a lot of material. I suggest giving the joint a try; it is a very strong joint and also adds a nice design element to your piece. You can use all different types of shapes, sizes and colors of pegs that help your joint standout. Experiment and have fun with it!