Cutting (floor) Board

Cutting boards are a valuable, and, at times, under-appreciated kitchen accessory.  In this plastic age, we have been overrun with sick, milky-white slabs of questionable origin, claiming to be safe and clean.  After a few weeks, you end up with a scarred, savaged scrap, un-saveable, collecting crud in all those crevices.  The alternative?  A solid, reclaimed hardwood cutting board made from old flooring, hand-rubbed with tung oil to a high, non-toxic sheen.  In a pinch, it's solid enough to chock the tires on your inlaw's RV, or knock a kitchen intruder unconscious.  It's also cheap (nearly free!), beautiful, and can be continually refinished, lasting for generations.  

I put this cutting board together with oak and maple floorboards pulled from old Chicago bungalows.  Save what you can from alleys, building sites, and salvage shops, get some good glue, and set aside an afternoon.  If you are lacking some of the heavier equipment needed -- thickness planer, pipe clamps, router -- you could laminate it together using the technique found in this table I did a few years ago:  https://www.instructables.com/id/Scrap-Table/

You will need these materials:

Reclaimed hardwood (not laminate of any kind!) flooring
Waterproof wood glue
Tung oil
Mineral oil

You will need these tools:

Table saw
Chop saw
Thickness planer
Jointer
Orbital Sander
Router
Clamps
Sandpaper
Rags

The first step, key to safety throughout this project, is to thoroughly de-nail the floorboards.  One nail can chip teeth off of a table saw blade, ruin a planer cutterhead, or fly up and take an eye out.  Go over the boards carefully and remove all nails and staples.  If you have a metal detector, use it.  Zircon, maker of stud finders, makes a handy pocket-size metal detector that is handy for this sort of thing, as well as finding wires in walls, rebar in slabs, etc.  

Slice off all the tongues and grooves on the boards with a table saw.  The best way to do this is set the saw to one width, run all the boards through once, then set to your second width and run all the boards through again, cutting the other side.  Now the boards are de-tongued and de-grooved as well as cut to the same exact width.  This will help get the cutting board flat and even later.  

The old finish on the tops of the floorboards will interfere with the glue adhering properly.  I ran the boards through a jointer to remove it.  That said, you could use a belt sander, a chemical stripper, or a product like Gorilla Glue that is less affected by non-porous surfaces.  

To remove the channels routed in the underside of the floorboards, run them through a thickness planer.  Yous hould now have a pile of clean stock, with no tongues, no grooves, no channels, and no varnish.  

Spread waterproof wood glue evenly over the flat surfaces of the boards, then clamp them together with heavy-duty pipe or bar clamps.  Alternate the clamps over and under the stock so it doesn't bow or bend.  Once the glue has dried a little bit, use a putty knife or razor to scrape up all the glue boogers.  If you don't have the heavy-duty clamps required, you could pre-drill, counter-sink, and screw each layer to the next with galvanized screws along with the glue.  This is more laborious, but perhaps cheaper.  I wouldn't be super-psyched about the long-term stability of that system, but it might work for awhile.  

I glued together the broad sides of the stock, leaving the narrow edges exposed, because the narrow edges are essentially quarter-sawn, meaning a stronger edge of the grain is exposed.  This will make the surface stand up better to your knife.  Secondly, gluing the broad sides puts a lot more surface area in contact with glue and one another, making for a much stronger, more stable board over years of expansion and contraction with changes in weather and humidity.  

Run the finished board through a planer, and then sand with 80, 100, and 120 grit sandpaper to get it flat, smooth, and even.  Then, put the whole thing on the chop saw and cut into blocks.  My original slab was about five feet long and a foot wide, leaving me with four decent-sized cutting boards.  

To round over the edges, run the boards through a router table with a generous-sized roundover bit, or use a hand-held router, clamping down the board as you go.  

To make the juice channel around the edge, make a simple jig for the router.  Depending on how your router is set up, you may be able to simply clamp and adjust a guide that allows you to run straight lines parallel to the edge of the board.  If not, simple screw a few pieces of scrap onto the baseplate, as show, to make a simple guide.  Put in a channel-shaped bit and set it to about 3/16" deep.  Mark a line around the edges of the cutting board, one inch in from each side.  As shown in the video, drop in at a corner, run down to the next corner, tip up, rotate to the next side, and continue.  Finish it out with hand-sanding.

I finished my board with a base coat of tung oil, to bring out the grain.  Tung oil is non-toxic, all-natural product.  Look for a brand that uses natural citrus driers and thinners instead of petroleum distillates, so it's food safe.  Once that coat has dried, saturate the surface with mineral oil, a clear topcoat you can get in the stomach-remedy aisle of any drugstore.  Rub the oil in, buff it out, and let dry for several days before your first use.  

When you wash the board, dry immediately with a towel.  Don't let it sit in water.  After years of use, when the surface is heavily marked up, just sand down and re-oil.

Enjoy!