Dec 17, 2017

Farmhouse Table

photo of finished wooden table

We needed a dining table, so I made a table! I bought wood from a lumberyard, then spent two months in the HobbyShop trying to finish this in time to put food on it for Thanksgiving (spoiler: just barely did it in time)

Wood required for this project:
  • 5 6ft 2x10s
  • 4 6ft 2x4s
  • 2 6ft 4x4s
as well as assorted 1" wooden dowels and miscellaneous hardware. I'll point out the important ones when they get used.

The first step, as always, is a planning sketch. I got inspiration from a google images search with terms 'farmhouse trestle table', but wanted to include some personal touches like tapered legs and breadboard ends.

sketches of wooden part dimensions

I started with the top. I squared-up 2x10s with the jointer and tablesaw, and glued them up.

tabletop boards dry-clamped together
Clamping boards down to check for warpage

pencil markings on boards ensuring that they get glued in the correct order
Drawing all over boards to mark grain orientations I'm happy with

top view of glueup that shows thin slivers of wood protecting the tabletop from clampsphoto of tabletop boards being glued and clamped together

A note about grain orientation for long glue-ups like this. The standard dimensional lumber I'm using is plain-sawn (as opposed to quarter sawn). Being plain-sawn (flat sawn) means that the boards contain the curvature of the growth rings.

plain sawn (left) cuts flat slices across the log, so each plank's cross section contains smiley-face-shaped curvature. Rift (middle) and quarter (right) sawn take radial slices, so the resulting planks have more uniform and straight grain in cross-section
This also means that since moisture loss is greatest along the growth rings, plain-sawn boards in particular are prone to curling away from the direction of the growth rings. This webpage does a good job of explaining the phenomenon further:
This kind of warpage, called cupping, only curls the board around 1/8", but to prevent a runaway feedback loop it's good practice to alternate the grain orientations on adjacent boards. This way it averages out and is less apparent in the final tabletop.
diagram of two planks next to each other, one with wood grain in smiley-face (curving upwards) orientation and the other with a frowny-face (curving downwards) orientation
Glue boards so that the endgrain lines up like so
I leaned up my glue monstrosity against a wall and started working on the frame components. First up were the 4x4 legs. I wanted to make them slightly tapered, so they would look less like dimensional lumber. To cut repeatable tapers, I made a bandsaw jig that fit the miter track.

4x4 held at an angle to the bandsaw blade using a plywood jig
leg clamped down in the jig

jig consists of a piece of plywood screwed at an angle stacked on top of a plywood base plate. Two clamps on top hold the wood to the jig.
side view of jig

piece of already-cut wood being realigned on the jig to cut additional faces
note the tapered shim on the bottom to compensate for already-cut sides
After tapering the legs, I cut each one of them to proper length. I relied on google's estimate of 30" for the average height of a dinner table. I also used the cut-off tapered scraps as shims to align the legs on the chopsaw (otherwise they wouldn't sit flat.)

when tapered shims are added, the wooden leg lies square against the cutting tabletable leg being cut by a chop saw

Following that, I used a V-shaped jig to cut a 3" flat into the tops of the legs. The mounting bolts will go here.

V-shaped jigs allow the tapered-square leg to rest on its diagonal
cutting the flat

the V-jig also works to hold the leg in a vice for hand-sawing
cutting the flat
In the interest of making an entirely disassemble-able frame, I'm mounting the legs to the apron using these premade corner brackets. I marked bolt locations with a punch, then drilled pilot holes on the drillpress.

drilling holes at the punch marksUsing the bracket to mark where to drill holes
I threaded on the hanger bolts using a nut and a socket wrench (the two ends have different thread sizes, so the nut bites on enough to apply torque with the wrench.) Afterwards, I repaired the threads using a die.

the author using a die to reform any smashed threads on the boltdoublesided bolts screw into the wood and have threads to accept fasteners, but do not have a convenient hex surface to attach a wrench to
Last step on the legs was drilling clearance holes and adding threaded inserts to the bottom to accommodate adjustable feet. Then the legs were done!
threaded inserts provide screw access in the endgrain without splitting the wood
Hammering in threaded inserts

photo showing four complete tablelegs

Moving on to the apron, I cut 2x4s to size and then added a thin dado using the tablesaw to accommodate these Z-clip table fasteners. Clamping the tabletop to the apron using these slots will allow for seasonal moisture expansion and lessen the chances of cracking the table.  

pieces of wood with long thin slots cut along one face

Because the legs are tapered, I needed to taper the ends of the apron as well. I measured the leg angles and set the chop saw to a 1deg angle (this ended up being slightly too much, but the gaps aren't too noticeable)

chop saws can be rotated relative to their fences
Setting chopsaw angle
I used a kreg jig to drill pocket holes for the lateral (front-back) stretcher pieces and the center apron reinforcement. Since I had tapered the lateral stretcher pieces already, I used my cut-off shims to compensate for angle (lower left photo).

kreg jigs have guide holes to enable drilling at shallow angles without splitting or splintering the wood

apron pieces with screw pockets for attaching to tablelegsdrilling screw pockets into wooden beams using a kreg jig
Then I dry-fitted the frame and pronounced it done! I packed away the frame pieces and continued work on the tabletop.

table frame screwed together but not yet glued. The background contains large planks of wood lying against the wall and many shelves of tools
Dry-fitting frame. Look at all the lovely HobbyShop space in the background

My original plan was to only have thin breadboard ends as aesthetics and protection for the endgrain, but then the HobbyShop shopmaster went on a rant about how fine furniture's details needed to serve more practical purposes than just aesthetics and that I needed to do breadboards right.

Suffice to say, I ended up making proper breadboard ends and it was overkill.

sketch diagram of breadboard dimensions. Breadboards are narrow pieces of wood that cover the ends of the main tabletop planks 

Breadboard ends serve two purposes. First, they mechanically counteract cupping (see note on grain orientation above.) Second, they reduce exposed endgrain surface area (endgrain is more fragile).

Properly-attached breadboard ends need to allow for wood expansion; otherwise stresses will crack the table. This rules out glue as a reasonable attachment mechanism. Instead, I chose to use woodmagazine's method of concealed mortise&tenon + dowel slots. I also decided to use popularwoodworking's method of combining the mortise&tenon with a tongue&groove joint, which allows me to make more concealed mistakes without sacrificing structural integrity. (popularwoodworking also has an excellent guide to breadboard ends in general, check it out)

As a final detail, I chose to make the mortise&tenon have a slight shoulder above the pockets. Since I'm an amateur and was certain I wouldn't be able to get the breadboards completely flush, I wanted to ensure the inevitable gap would get concealed by some wood versus going through the entire table. This ended up being a good call even if it made everything else more complicated.

I marked up both breadboards with a marking gauge, then tried mortising them on the mill. That went terribly (board was too tall and vibrated loudly).

attempting to bore a pocket in a piece of wood using the millUsing a marking gauge to scribe a half inch offset from the sides of the board

Second attempt was with the mortising machine (new tool!), which went much better. With this machine (effectively a horizontal mill), the workpiece is clamped flat while the tool is moved in XY with a joystick lever. Stop-nuts on the ballscrews let me set a repeatable mortise width and depth.

First I milled out the pockets, then went back and did the shoulder mortise.

A mortising tool is effectively a drill press spindle lying flat on a table, and can cut notches into the sides of wooden planks
I marked the far edge of each mortise to keep even spacing

Cutting the shoulder mortise, which is a shallower pocket than the deep notches
Shoulder mortise

two planks of wood with mortises for each of the tabletop ends and a shoulder pocket
completed breadboards
With breadboards done, I put the tabletop on sawhorses and cut it to size with a track saw. Then, I scraped off excess dried glue and started cutting tenons with a plunge router.

photo showing a clamp jaw slotted into a recess on the underside of the aluminum track
This tracksaw is cleverly extruded to have built-in channels for clamps

a photo of the tabletop on sawhorses, with dowel plugs, measuring tools, and a notebook scattered on top.
Planning phase
a tracksaw track is a long, narrow aluminum plate with a rail to cut straight for long distances
The tracksaw track also makes a great straight-edge guide for the router

I routed both shoulder-depth and tongue-depth tenons, then flipped the tabletop over and did the same on the other side. I then used a saw to form the tongues. Luckily for me, this process cut out the tear-out on the outer edges of the tabletop and let me hide my bad technique!

photo showing some splitting in the wood on the outer edge of a tenonsawing off the outer edges creates square, clean surfaces

Because my mortises were cut using a routing bit, I needed to round off the sides of the tongues. I did this with a coarse file. The process was very trial-and-error, but eventually both parts fit snug.

photo of the tabletop with four wooden tongues ready to slot into the breadboard pockets

Once the breadboard was attached, I drilled the 3 dowel holes that need to become slots (to avoid overconstraint). One hole is left for later, because it remains circular. Drill bit used is a forstner bit, which produces the crispest edges.

holes are drilled through the breadboard-tabletop assembly before enlarging the tenon holes into slots.

Then I pried the breadboard off again. Drilling dowel holes through both breadboard and tabletop in one operation ensures that my slots are located in the right place.

photo of tabletop with breadboard removed, showing holes drilled into three of the tenons

After creating slots with a round file, I reattached the breadboard, pounded in dowels, then cut them flush. I only added glue to the uppermost section of the dowel - having the dowels glued to the tongues would make the slots useless.

cutting the excess dowel ends with a hand sawtenons with holes enlarged into oblong slots

State of the tabletop! Left side is waiting for glue to dry before cutting them with the flush-cut saw.

tabletop with one breadboard's dowels cut flush

I waited a day for glue to dry, then got Coby and other members of the HobbyShop to help me maneuver this tabletop to the thickness sander. That tool was an immense time-saver, turning a roughly multiple-day sanding job into 3 hours of work.

After cleaning up sawdust, I applied two coats of satin wipe-on polyurethane (1000-grit sanding between coats). The frame parts got one coat.

polyurethane increases contrast in the wood grain. The end grain of the dowels becomes much darker than the surrounding wood.
Revealing the pretty colors is the best part!

table components stacked near each other for air drying
All parts finished and drying
I never understood why most woodworkers immediately paint or stain their pine/fir pieces. I actually really like the warm golden color.

top view of tabletop showing off the matte sheen from the polyurethane

Once dry, these pieces all got bundled into a hatchback by my tetris-genius roommate and unloaded into our kitchen. I assembled this table in an evening, where the longest step was centering the tabletop over the frame. Tools required: screwdrivers (and drill because I'm lazy) and pliers.

A two-month project: done!

underside of the assembled table showing the tabletop attached to the apron with screw-in clips
Unclear what's going on with the whitebalance in this/next picture

photo of table in the author's kitchen
Assembled table!

photo of table with platters of thanksgiving foods arrayed for serving
Finished in time for Thanksgiving

photo of the table with breakfast laid out on it
celebratory coffee and cheesecake

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