Archive for July, 2013

The Eleven Grooved Box – Tools

I am a big fan of Roy Underhill’s “The Woodwright’s Shop”.  Last fall was the 32nd season, and he’s still wearing the same hat.  The second episode was titled “The Eleven Grooved Box”, a project Roy uses in his woodworking school. You can see it here.  I was attracted to this project because he uses Stanley 45 combination planes to make all eleven grooves.  I have a Stanley 45 and have been looking for an appropriate project so I am trying to duplicate what Roy does as closely as I can.

11GrooveBox

Finished Eleven Grooved Box. Red Oak from Home Depot.

11groove2

The finished box opened up. About 6″x8″x4.5″. Golden Oak stain and Watco natural oil.

You should watch the half hour video to see how Roy makes the box. I am going to document how I do it, and pass along some things I learned, and in particular, show how I made those #$%@! spline grooves.  Each corner of the box has to have two matching grooves plowed for splines, without these the box would be very weak.  You can see these in the corners of the lid in the photo.  Cutting those spline grooves with an old  Stanley 45 might be easy for Roy but for everyone else it’s a pain.  A millisecond of inattention and the sides of the groove are ripped up.  So like any self respecting woodworker, I made a jig.

My grooving jig for the Eleven Grooved Box

After almost giving up on this project, I sat down and analyzed what is happening. When plowing the grooves, you have to hold the plane perfectly perpendicular to the 45 degree mitered surface. The fence on the Stanley plane rides on the reference surface. But the skate is captured in the plowed groove! If you let the plane roll to the right, the fence lifts off the reference surface a bit and not much happens. But if you let the plane roll to the LEFT, the fence digs into the reference surface and pulls the blade to the left. The result is a horribly shredded edge on the left side of the groove. In the video, Roy has an Iron Arm and holds that Stanley perfectly aligned through the whole operation. My arm is made of rubber so I knew I had to make a jig to get the plane to behave.

V1.0 – My first jig attempt was a piece of 2×6 cut off at one end at 45 degrees, with a stop block attached. The stop block helps control tear out at the end of the cut and makes it easier to initially align the work piece with the plane. It did not help with the left side shredding problem, in fact made it worse.

V1.0

First attempt at a jig for cutting spline grooves

V2.0 – Added a second 45 degree cut at the end of the 2×6, creating a 90 degree angle at the tip. That spaced the work piece farther away from the fence face. I reasoned that the longer roll radius would pull the blade over less if I let the plane drift off axis. It helped a little but still not satisfactory.

V2.0

Second attempt at a spline groove jig

V3.0 The third revision adds a second reference surface for the BOTTOM of the plane fence.

.V3.0

Third attempt at a spline groove jig

The fence is now constrained by hard surfaces in the down and right directions, and in the up and left directions by my left hand. It can only move back and forth like it’s supposed to.  The whole thing gets clamped in a bench vise for the plowing operation, just like in the video.

45onJig

The Stanley 45 in working position on the V3.0 jig. The fence is riding on two reference surfaces

The bottom reference surface is constructed at the rear of the jig by screwing on a 3/4 piece of scrap cut off at 45 degrees at the top. That 45 degree surface is 90 degrees from the fence reference surface of the jig. The two screws are in elongated slots so the added piece can be adjusted up or down, which in turn moves the small block of hard wood up and down the fence reference surface. I made a one time tweak so the plane is level and aligned with the work piece bevel at the beginning of the cut and tightened the screws.

FenceBottomSupport

Showing the jig with added fence bottom support

There is a small block of hard wood on which the plane fence actually rides, that sits loosely on top of the added piece.

JigSpacer

The hardwood block in working position

The hardwood block has screws inserted in each end so it won’t slide off the jig when the plane is working.

FenceBottomSupportSpacer

Hardwood spacer block showing screws that keep it from sliding away

I start the cut with one light pass at the end so I can see where the plane is plowing, then knife down the grain like Roy does. With that, and the v3.0 jig I’m getting perfect spline grooves in the mitered surface.

Finigroove

An end piece with groove cut using the V3.0 jig

Stanley 45 tips for the Eleven Grooved Box

1. The eighth inch wide inch cutter needs to be as sharp as possible. I use one of the cheap “Eclipse Style” honing guides. I had to file the rounded jaw slightly to get it to grip the small cutter firmly. Use a simple wooden stop gauge to set the cutter for a 35 degree sharpen angle. Then the problem is, the narrow cutter can’t keep the gauge from wobbling during the honing process. The local hardware store had nylon bushings exactly the same diameter as the guide roller, with an ID the same as the guide screw shaft. I pulled the knob off the screw shaft and hacksawed a screwdriver slot across the end. With the knob removed,  I can put a nylon bushing on each side of the guide and they act as outriggers to keep the whole thing true to the stone.

CheapGuide

Modified honing guide with eighth inch cutter and outrigger wheels

To be really sharp, you have to flatten and polish the back side of the cutter as well. This is complicated by Stanley having made the 45 cutters slightly curved. You can use the Charlesworth ruler trick but you will need a thicker than usual ruler because of the curve. I found it good enough to just free hand polish the back by putting a lot of finger pressure on the tip.

2. Use a good ruler and measure the distance between the fence and the skate at front and back. Mine is typically wider at the rear, which causes the skate to bind in the groove. Loosen the fence rear lock screw and push it around until the measurements are the same.

3. Wax (Paraffin from a candle) the face of the fence, the bottom of the fence, the bottom and side of the skate.

4. Don’t overtighten the cutter lock bolt. It doesn’t take much to hold the eighth inch cutter in place.

5. Use an eighth inch drill bit to set the depth stop. When the groove is finished, lay the drill bit in the trench and if it sticks up above the beveled surface, back off the depth stop and cut a little more.

Glue up tips for the Eleven Grooved Box

1. Glueups have to be rehearsed.  Make sure you can get the box assembled before the glue starts to grab.

2. I’m using Titebond III which has a little bit longer open time than Titebond II. I don’t have a Roy Underhill style glue pot.

3. Use an acid brush with the bristles cut off to about 3/8 inch to apply glue.  Avoid applying a lot to the inside edge as squeeze out is difficult to remove there.

5. Apply glue to all the miters and grooves then wait a minute for that to soak into the end grain. Then apply another coat of glue and insert the splines. An easy way to apply glue to the splines is to lay a sheet of foil or waxed paper on the bench, make a puddle of glue, and roll the spline around in that.

5. Don’t forget to insert the top and bottom panels. DAMHIKT.

Eleven Grooved Box Step by Step – Part 1: The First Three Grooves

The First Three Grooves

See the original “Woodwright’s Shop” video here.

I’ve made about a dozen of these now and will document the next batch here with photos.  Most of the boxes I’ve made lately are in Cherry or Walnut and are pencil box size, 3″ x 8″.  These next few will be larger, sized to hold 3″ x 5″ index cards.

The lumber for this project is leftover tongue and groove wainscoat paneling from my fathers house circa 1974. These were milled 5″ wide and 11/16″  thick. He never finished the basement so after 35 years, some of the stock was available. The Cherry had darked quite a bit and that had to be planed off to get an even color on both sides of the boards.

I cut 24 inch sections and resawed to produce a 3/8″ slab for the box sides, and a 3/16″ part for the top and bottom.  Should be a great grain match. The first board was resawn by hand with a good old Disston rip saw but I did not like the results.  It’s too hard to get a clean line and is a LOT of work.  The other boards I resawed on a table saw.  All were cleaned up and thicknessed with a Dewalt lunch box planer.  That will be the last power tool used on this project, all hand tools after that.  I suspect the lumber Roy uses in his classroom and the video comes from Lowe’s (it is 3 1/2″ wide) so I don’t feel bad about preparing the stock with power tools. Planer scallops and snipe were removed from all faces with a #4 smoothing plane.

The thin strips in the center of this photo were ripped from another piece of cherry. They will form the box lips.

Lumber

wid Cherry cut to make four boxes

The boards still have parts of the tongue and groove machining which had to be removed.  Here I’m using a 100 year old Stanley 606 to shave off the unwanted projection.

Planing edges

Cleanup edges

My planing discipline is not that great.  I admire people like Roy and Bill Anderson who can unerringly carve off a perfect 90 degree edge free hand.  I have to cheat. I have this little Stanley 95 edge plane that is made for truing up board edges.  A couple of passes is all it takes.

Truing edge

Truing edge

The workbench in my shop is a recycled office desk, is not very flat, and no end vise, so some time ago I made a flat plywood planing board. It has a cam arrangement to clamp the workpiece. For these thin pieces I have to raise the work up to clear the stops. I use old printed circuit board material under the workpiece.  With the 3/8″ material clamped and aligned with the planing board edge, I can cut the first 1/8″ groove.  This will hold the bottom of the box and is cut against the grain of the lumber.  The Stanley 45 does not seem to mind grain direction much.

Groove One

Groove One

Groove number two is also 1/8″ and is made by flipping the workpiece 180 degrees, and plowing the other edge.  This will hold the top of the box and is cut with the grain.  I have switched to the short rods in this photo.

Second groove

Second groove

Groove number three is a wide 5/8″ and will ultimately hold the lip.  I can cut this with the same board set up as groove #2 which is why groove 2 is set up with the grain.  Groove 3 is spaced down far enough so 3×5 cards will stick out a bit from the box bottom.

All these grooves are started far end first and gradually worked back to the near end. This technique gives the front of the skates a channel to follow as the groove lengthens and deepens.  To minimize skate dragging against the side of the groove, It’s important to check during set up, that the skates are parallel with each other and parallel to the fence. Waxing the skates with paraffin once or twice during the operation helps a lot.

Groove three

Groove three

For the lip groove, I’m using both depth stops as Roy does in the video, each set to 1/8″ depth. Here I’m checking groove depth with a 1/8″ brass block.  A set of these gauge blocks is very handy.

Depth check

Depth check

Eleven Grooved Box Step by Step – Part 2: Fitting the Lip Strip

Fitting the Lip Strip

See the original “Woodwright’s Shop” video here.

In the center of the first photo in Part 1, you see narrow strips of Cherry.  These must be precisely fitted into groove #3 before the board can be sliced into four box sides.  The strip forms the lip around the inside of the box bottom that the lid seats onto.  Roy glosses over this step in his video, he uses a strip already planed to width.

I was using a “Moxon” style vise wide enough to clamp a 24 inch strip for planing but found it didn’t hold securely enough to work the edges. Also it was a pain to insert and remove the strips. The strips are flexible enough in the wide dimension to bend and cause trouble while you’re planing.  That’s probably why Roy skips over this step. I now have a better method using the dog holes on my nice flat planing board.

I insert pegs in the holes at about a 6 inch interval then weave the thin strip around them.  This has several advantages:

  • holds the strip edge flat against the planing board
  • provides a wider surface for the plane so you get a truer planed edge
  • off and on in seconds for a trial fit in the groove.

The photo shows one of the strips and the board it will be fitted into.  I’m using the #6 Stanley which has a bed long enough to nicely ride the curved strip.

Preparing to trim lip strip

Preparing to Trim Strip

It takes many tries to get the strip to fit tightly. Sometimes part of the strip fits but in other places it’s too wide, then a block plane is best to shave a small area.  It’s not fatal to have the strip a bit loose in a few spots. It just has to stay in place during the next planing operation, and while slicing the board into four mitered side pieces.

At this point, the strips project above the side stock about 1/16″, I tap them in with a rubber mallet to make sure they’re seated in the groove.

Four lip strips fittec

Four Lip Strips Fitted

Next, the fitted strips get planed down level with the grooved board.  I use a thick set block plane to remove most of the protrusion, a longer bed 5/1/4 plane to get it almost even, then a #4 smoother over the whole surface until the strip is perfectly flush.

Four lip strips fittec

Leveling Lip Strip

At this point if there is some tearout to clean up, I scrape and sand the entire surface as it will be awkward to smooth after it’s sliced up into side pieces.  I sand to 280 grit because I have a lot of 280 paper.

Sanding the inside surface

Sanding the Inside Surface

Eleven Grooved Box Step by Step – Part 3: Slicing and Tuning the Box Sides

Slicing and Tuning the Box Sides

See the original “Woodwright’s Shop” video here.

This is a Stanley Miter Box, same as the one Roy uses in the Video.  The huge back saw will cut just over a five inch depth. In the video, Roy holds the stock with his left hand but I had trouble with the board moving so I use a couple of clamps. The side of the stock with grooves and lip strip is always facing the Miter Box fence.

Here I’m making the first 45 degree cut on the leading end of the stock.

First Cut

First Cut – Stanley Mitre Box with Grooved Stock Clamped in Place

These boxes will hold 3×5 cards so I use a sample card to lay out the inside length for the second cut.  It will be about an eighth inch longer than the card, and the mark is on the inside of the next miter. This will form the front of the completed box.

Marking for Second Cut

Marking for Second Cut using 3×5 card

Now the stock is flipped 180 degrees and clamped on the right side of the Miter Box. The second cut is made just to the right of the pencil mark.

Second Cut

Second Cut

The future box front has been sawn from the grooved stock with lip strip included.

Completed Box Front

Completed Box Front

Fiip the stock back to the left side and trim off the miter from the first piece.  This will be the first cut on the next section, forming the left side of the box.

First Cut for Second Piece

First Cut for Second Piece

How long should the box sides be?  The inside edge of the two miters have to fit between 1/8 inch rabbits on the thin top stock. So I use the actual top stock to mark for the cut.  Best to err on the narrow side here, as I can always trim the top stock a bit.

Remember that wood moves when humidity changes so the top has to be a little loose in the cross grain direction. This is actually “Frame and Panel” construction, the top and bottom pieces float free in their grooves.

Measuring Box Side

Measuring Box Side

The third piece sliced from the grooved board will form the rear of the box.  Here I am using the front piece to lay out where to cut.  I will actually cut a bit long and trim this rear piece to match the front later.

Marking Length of Rear piece

Marking Length of Rear piece

The fourth and final piece forms the right side of the box and follows the same procedure, matching length with the previously cut left side.

I put pencil dots where they won’t show in the bottom groove to keep track of the order the pieces were sawn out.  Assembling them in order maintains the flow of wood grain around the completed box sides.

Later, I will use the dot method to keep track of the lip strips as they are pried out.

Dots inside bottom groove

Dots Inside Bottom Groove

Now that all four sides are sliced out, I clean and trim each to exact size on the Shooting Board.  First I use a utility knife to relieve the leading corner of the two exposed grooves. This keeps the plane from tearing out that delicate edge.

Relieving Leading Corners

Relieving Leading Corners

On the first (front or left side) piece it’s only necessary to take a couple of clean up strokes.

On the Shooting Board

On the Shooting Board

The mating second piece (rear or right side) is always sawn a bit longer than the first. It’s cleaned up and then trimmed until it’s length exactly matches the first piece.  The photo shows the front and rear pieces back to back.

Matching Length of Front and Rear Pieces

Matching Length of Front and Rear Pieces

With all four pieces cut and tuned to length, the box can be dry fit with a couple of rubber bands around it, to check the miters.

DSCF0096

These miters fit pretty good.  If they were off, I would tune the Shooting Board miter attachment and re-shoot the miters. It’s adjusted by adding or removing strips of thin cardboard underneath. I use playing cards.

The technical term for this sideways holding fixture is a “Donkey’s Ear”. Having never owned a Donkey, I can’t comment on the name. It is simply a block of scrap cut at 45 degrees, and a thin bit of scrap screwed to the end for a stop.  I glued sandpaper to the 45 degree face to help keep the work piece from moving around.

Shooting Board with Donkey's Ear Attachment

Shooting Board with Donkey’s Ear Attachment

On a Shooting Board, the plane blade is vertical. It helps to get through the cut if the plane has a lot of mass so I use the big Stanley. Since it’s planing end grain, it must be very sharp and take a fine shaving.

The whole thing is clamped to a convenient massive surface (table saw).

Shooting Board with Stanley #6

Shooting Board with Stanley #606 in Working Position

Eleven Grooved Box Step by Step – Part 4: Plowing The Other Eight Grooves

Plowing The Other Eight Grooves

See the original “Woodwright’s Shop” video here.

I remove the lip strips and set them aside.  Each gets pencil dots on the bottom so it can be returned to it’s original position in it’s original groove. Dots are placed where they won’t show in the assembled box, bottom of the strip and lower half of the groove.

Marking Lip Strip and Mating Groove

Marking Lip Strip and Mating Groove

The jig I use to cut the spline grooves is discussed elsewhere on this BLog.  Here the first box side piece is clamped in the jig by the bench vise.  This particular board is warped slightly and won’t lie flat against the jig so I use a couple of F clamps to pull it tight.  If the grooves are not cut consistently, they won’t line up properly. Have to make sure the F clamps don’t interfere with any part of the plow plane.

Side Piece Clamped in Spline Groove Jig

Side Piece Clamped in Spline Groove Jig

In the video, Roy knifes the sides of the uncut groove at the exit point to control tearout from the plow plane.  He guesses where the groove will end up and misses the mark quite a bit.  My solution is to set the plane on the jig, put downward pressure on the main skate, and pull it back across the work piece.  This leaves a mark across the miter and you can clearly see where to place the knife.

Mark from Pulling Blade Backwards

Mark from Pulling Blade Backwards

Hold the knife perpendicular to the miter surface and cut down both sides of the groove an eighth of an inch. It doesn’t hurt to knife edges at the beginning of the groove also, where the blade is dragged back across on the return stroke.

Knifing the Exit Edge of the Spline Groove

Knifing the Exit Edge of the Spline Groove

At first I was still getting exit tear out at the bottom of the groove (and Roy does as well), so I made this little chisel from eighth inch key stock. It’s sharpened at a 25 degree angle.

Utility Knife and Homemade 1/8" Chisel

Utility Knife and Homemade 1/8″ Chisel

I set this in the groove in the stop block and give it a tap with a small hammer.  Now the wood fibers are precut on all three sides of the groove and most plow plane tearout is eliminated.

Knifing the Bottom of Spline Groove Exit

Knifing the Bottom of Spline Groove Exit

With the board secured and all preparation complete, the actual plowing of the spline groove commences. Even with the jig it takes a lot of discipline to keep the plane moving in a perfectly straight line.

The 45 is cutting across end grain so the cutter has to be as sharp as I can get it.  I will hone it after every other box (16 grooves).  Also at the beginning and when the groove is cut about half way, I stop and wax the outside of the skate with paraffin.

Beginning the Spline Groove Cut

Beginning the Spline Groove Cut

The reward is a perfectly executed groove 1/8″ wide and 1/8″ deep with no tearout on either top or bottom edge.

Completed Spline Groove

Completed Spline Groove

I’m making four boxes with this project, so 31 more grooves to go!

DSCF0199

One done, 3 to go

And they are now all cut! One finished box and three sets of sides ready.

Eleven Grooved Box Step by Step – Part 5: Making the Splines

Making the Splines

See the original “Woodwright’s Shop” video here.

Splines are made cross grain. This makes the strongest joint, but the thin blank will be fragile before gluing into it’s ultimate home.  I like to use contrasting wood, Walnut for these Cherry boxes, Aspen for a Walnut box.  The first step is to rip down a piece of scrap leaving slightly more than an eighth of an inch of wood.  If you’re careful you can get three splines at a time out of a 3/4″ board.

Resawing Scrap Walnut to Make Spline Blanks

Resawing Scrap Walnut to Make Spline Blanks

Move to the miter saw and slice off the end of the block to make blanks a little wider than a quarter of an inch.  Contrary to what Roy says in the PBS video, it’s OK to be a little bit off as these will be planed down on both sides anyway.

Also it’s OK if the blanks are somewhat short. Just cut them in the middle and when gluing, spread the two pieces out so the empty space is in the bottom half of the box where it won’t show.  Ideally, you want the spline long enough to protrude about 3/16″ from the ends while gluing so you can plane down to a clean end after the glue sets.

Cutting Raw Splines From the Scrap Block

Cutting Raw Splines From the Scrap Block

My jig for sizing the splines is very similar to Roy’s. I had a piece of Apple wood from the back yard and used the Stanley 45 plow plane to make two grooves, one for thickness planing, the other for width.  I first glued dowel pins in the grooves to make end stops but an improvement later was to make the stops removable. Sooner or later the jig surface gets shaved down too much and you have to recut the grooves. Don’t Ask Me How I Know This.  After the blank is planed to thickness in the wide groove, it is rotated and moved to the narrow groove where it’s planed to width.

It’s difficult to read the grain of these small strips, I just try different orientations in the jig and use the one that planes the best.  It’s common to break a strip while planing.  That’s OK if the break can be placed in the bottom half of the box where it won’t be seen.

Planing the Rough Spline to Width

Planing the Rough Spline to Thickness

Another photo of the sizing fixture with blanks in each slot.  I fine tune the jig grooves by inserting strips of paper cut off the sticky end of a large Post It Note.  That block plane BTW is not a Stanley 18, it’s a knockoff Craftsman 5256 probably made by Miller Falls.

Jig For Sizing Splines

Jig For Sizing Splines

The best way to check a finished spline is to insert it into the dry fit box.  This is a bit loose, but if using water based glue, the splines swell as soon as they have glue applied so you don’t want them to fit too tight at this stage.

Spline Test Fit

Spline Test Fit

Finally four sets of four box splines trimmed to size.

Note to self: Next time cut the blanks closer to final size so don’t have to plane off so much.

Four sets of walnut splines

Sixteen Splines

Eleven Grooved Box Step by Step – Part 6: Making the Top and Bottom Plates

Making the Top and Bottom Plates

View the original Woodwright’s Shop video here.

I make these recipe card boxes are made from 11/16″ Cherry paneling that was resawn to yield 3/8″ thick (sides) and 3/16″ (top,bottom) boards. The top and bottom must be trimmed to exact size and thinned at the edges to fit into the prepared grooves. I have kept the resawn slabs together so the grain and color matches.

The first step is to slice off from the best end of the 3/16 stock, just enough to make the top and bottom plates. In this case, 11 1/2 inches.

Cut stock for top and bottom plate

Cut stock for top and bottom plate

The lid stock is slightly thicker than the 1/8″ grooves in the sides so I use a plane to rabbit the edges until they fit. My moving filister plane is a kludged up dado plane. It has a nice skewed blade and a separate nicker, so I just had to add a homemade fence.  I adjust the fence to reveal an eighth inch of main blade.  It only takes a couple of passes to reduce the plate thickness to an eighth inch so the depth stop can be set very shallow.

Proper protocol for rabbiting end grain with one of these is to first draw the plane backwards with a good bit of pressure, across the end. This causes the nicker to cut a starting line across the board. It reduces tear out where the blade exits the board.  I help the plane out by knifing the exit end of the line a bit. Always do the end grain first, then the long grain edges. If there is any tearout at the exit, rabbiting the long grain may clean it up.

Rabbit end grain edges to 1/8 inch

Rabbit end grain edges to 1/8 inch

I do one end grain edge and one long grain edge before marking the final sizing saw cut. That way I can mark both final dimensions from the dry fit box at one time. Here, I am checking the thickness of the edge with one of the side offcuts after rabbiting.  A slightly loose fit is preferred because this is frame and panel construction and the lid plates should be free to expand and contract with humidity changes.

Rabbit side to 1/8 inch

Rabbit side to 1/8 inch

Lay the rabbited edge over the dry fit box and carefully mark the other end at the inside edge. The width of the plate was spot on in this example, otherwise I would do the same marking procedure from the rabbit on the long grain edge.

Marking the other long grain edge

Marking the other long grain edge

Now square across the edge mark, add an eighth of an inch (using a brass thickness gauge here) and mark across the plate for the second cut.

Square across and add 1/8 inch

Square across and add 1/8 inch

The final steps are:

  • Cut off the plate at the line
  • Rabbit the remaining two edges as above
  • Trim a bit off each corner, helps keep glue squeeze out from freezing the plate in position
  • Repeat all these steps for the bottom plate.

This photo shows the dry fit box with both finished top and bottom plates ready for glue up. Pick the best plate for the top side and mark it with a bit of tape.  Also mark the top edge of all four side pieces with tape. This will keep things straight during the glue up DAMHIKT.

Finished top and bottom plates

Finished top and bottom plates

The final step before glue, is to decide where to make the saw cut that opens the box. You have to be able to see the lip groove to do this.  Measure down from the top of the box to a little above halfway in the lip groove and record this number. Later we set a marking gauge to this depth and score the outside of the box so it can be cut open properly.