Sunday, December 9, 2012

The Separation of Lid & Box


     One of the more common ways of making a lidded box is to make it as a solid piece and then separate them.  This way the grain is continuous and you know they will be perfectly aligned -- after all they were made as one piece!  The two most common ways of doing this is by using either the bandsaw or the tablesaw.  My preference is the tablesaw, it just seems to make a smoother and more uniform cut then the bandsaw does.
     In practice, it's simple.  Set the rip fence to the required size and cut away.  However, there is a potential for problems which usually occur on the last side cut.   What can happen is that on the final cut, the box and lid squeeze together resulting in a snipe. On a recent episode of Rough Cut with Tommy Mac he did this process but didn't do what I recommend doing.
    Here's what I suggest, first cut the two longest edges of your box completely through.  The blade is set slightly higher than the thickness of the box sides.  To cut the other two sides I'll adjust the blade so that it is 1/16"+ lower than the thickness of the sides which results in something like this:

Tablesaw Work to Separate
     What happens here is that you leave a small sliver of wood so there's absolutely no risk of squeezing the two sides together and causing a snipe or even a kickback.  Notice that I cut right in the middle of a finger joint so there is long grain on both the top and bottom.  All that's required now is to use a zero set saw to complete the cut.

Finishing the Separation

     You can hold the box either as shown or horizontally.  This results in a small fin of wood that can easily be pared or chiseled flush with the box.

Paring the Cut

     Now that the two are apart, it's time to check the fit of the insert ….

Success
                                                                                                         ……. it fits!

      Next step was to mortise in for the hinges.  These are a quality pair of solid brass hinges from Lee Valley.  I'm planning to use a set of Brusso hinges for my next custom box project.  They're not that much more than these and I've heard so much about the quality of them I believe they'll be worth the couple of extra dollars.  I use a template and bearing guided router bit to start the process.

Hinge Mortise Guide
     Hinge mortises need to be exact if the box is to close and open properly.  The mortise I route out is slightly less than the hinge length, 2" in this case.  Even though I align the template as carefully as I can, there's still a chance of being off.  To counter that I use a chisel to trim the mortise so that the distance from the end of the box and the outside edge of the hinges are exact.

Exact Distance from End
    Once that's set, the inside edge of the mortise is trimmed to fit the hinge.  I prefer to use slotted, solid brass screws for this type of project but they have a tendency to strip out or worse -- break off.  Not good so each hole is pre-screwed with a steel screw. Good insurance as far as I'm concerned, nothing worse than trying to remove a broken screw inside of a finished project and then fill the hole, re-drill, etc.  By the way, I prefer the slotted head screw because it gives the appearance that this case has been around for many, many years.
     The way the insert will be held in place is with strips of Sapele that will do double duty to not only secure the insert but also function as a dust check for the box.  After carefully fitting them in place I needed to taper the outside of the front one so the lid would close easily over it.  The other edges will have a slight round over.  These pieces are only 1/4" thick and 3/8" wide so no way could you use a router or even a small block plane.  I have the perfect solution for this; an old, Stanley #101.

Stanley #101
     When Adam was a teenager he went to England with his Dad and brought this little antique back for me.  Not sure if he figured I'd use it or that it was just a great memento to give me from his trip.  I've sharpened the blade and it's great for forming chamfers or quarter rounds on small pieces such as this.  I know it's an antique because the blade is stamped with the Stanley Rule & Level logo.  This plane was made from 1877 to 1962.  Since he bought it in England I'd assume that's were this particular model was made.  It's a neat little tool that has seen much use in the past and will continue as long as I'm able.
     Last up today was to shellac the dust check and the top edges of the newly separated box.  Diane is going to sew the felt covered, foam piece that will secure the flute in the case.  All that remains are a couple more hand rubbed coats on the outside followed by wax, apply the handle and nameplate, and this project will be ready for shipping.  I've met the Christmas deadline!

2 comments:

  1. I do my box cutoffs in similar fashion. I do the 1/16" less on all four sides and use a razor knife to separate the leftover web.

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  2. Sounds like even more insurance against the dreaded "snipe". Thanks, I'll have to try that on the next one.

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