Be sure to visit the Hand Tool Headlines section - scores of my favorite woodworking blogs in one place.  Also, take note of Norse Woodsmith's latest feature, an Online Store, which contains only products I personally recommend.  It is secure and safe, and is powered by Amazon.

Search

Building a Traditional Coffin Smoother

I've been meaning to build myself a traditional smoother, and while I was going to wait until other projects were completed, but decided I would forego some other projects and give it a whirl now.  The photo below is what I'm building on the next several pages - be warned, I tend to write in a "stream of consciousness" style, so forgive any rambling that might occur.
The plane built on these pages reflect closely a classic coffin smoother documented in an instructional pamphlet  titled "How to Make Wooden Planes", authored by David G. Perch and Leonard G. Lee (of Lee Valley and Veritas Fame).  Unfortunately this pamphlet is no longer available (inserted edit - Garrett Wade might have a few copies left).  Another good text on building wooden planes where a similar plane is constructed is John Whelan's excellent book "Making Traditional Wooden Planes", available from the Astragal Press.
David Perch has authored another book along with Robert Lee which might interest the reader, titled "Wooden Planes and How to Make Them", available through Lee Valley.  I've not read it myself, but it' my understanding it is a well written book.
Note: Notes formatted in this fashion were made later. in hindsight when I had a chance to reflect back on what had gone right or wrong.  I thought it would serve both myself and anyone else reading this better to learn from my mistakes and comment on them, than just to pass over them.  This seems like the easiest way to accomplish that.
I am assuming, with this documentation, that you the reader is familiar with the shape of the opening to be cut into the plane if you are interested in making one yourself.  If not, the shape is common to most wooden planes, and should be studied first hand before attempting your own.  But if there is one thing I have learned about woodworking, it's to jump in with both feet, and not be afraid of making a mistake.  The worst that can happen is you end up with some heavily worked firewood, but even that would have to include the learning and experience acquired during it's execution.  
Also remember, I am no "expert" (easily seen in the forthcoming work)- these are just my experiences in building this plane.
Collecting the Material and Preparing the Blank
The first thing I dug up in preparation for this little project was a double iron from a Stanley Handyman #4 size plane.  I've never been too happy with that old plane, but always figured I could use the iron for a project like this. 
Note:  The iron mentioned here did not end up being the iron I used for this plane.  This is because they proved to be quite worthless in the end, and it ended up being a mistake to use it here because of its low quality, and have now proved to myself why I was never happy with that particular plane.  But more on that later.
Next was to find some wood for the wedge. I found a blank of walnut about 2" x 6" that was perfect - contrasted with the maple and was a bit softer - just the right thing for it.
Next was to find a suitable block of wood for the body.  I had nothing on hand of substantial thickness, and as it was my purpose to spend absolutely nothing to build this smoother, I dug up some scraps of hard maple I had on hand, and glued them together to make a block of the proper depth. I then squared the block to 2-1/2" square and 8" in length.  I tried to orient the grain while gluing up the blanks and consequently while marking out the plane so the outer portion of the tree was to the bottom, and so the grain dived towards the back of the plane.
I mark the plane T for top, S for side, making sure to check for optimum grain direction.  I then scribe a line 3" back from the front of the block, followed by a line at 50 degrees to mark out the bed of the iron.  I then place the assembled iron against this line to determine the base line of the wedge that will be fit later:
Note:  It is very important that you make the marks telling you the side from the top and front from back.  This was actually the latest round of mark making on the blank because I caught myself doing it backwards...  Twice.  First I had the side on top - then the back at the front.  WHAT A PUTZ!  
As the wedge will be made at an angle of 12-1/2 degrees, this line is added to the blank using an angle printed out from a cad program on a piece of paper, then cut out to make it easier to mark out:
A similar one could be drawn out on a piece of paper using a simple compass.  To be most effective, the point of the wedge should end up about half way between the hump of the chip breaker and the bottom of the plane, which is why it the point does not quite reach the bottom in the picture above..