Final Layout of the Throat

Time to finish laying out the throat. Start by marking the location of back of the mouth and the top of the bed to the edge of the body of the plane, and connect those two lines on the side to show the bed location - the farthest right of the lines shown on the side of the plane body below:

These photos are a bit backwards, but the second line from the left is determined using the iron.  Line the bottom of the iron up along the bed line you just made, and using a ruler, transfer the thickness of the iron onto the side of the plane:

 

When that line is established, I use a cutout of a 12-1/2 degree angle to help me layout the furthest left line on the side of the plane above - the line for the shoulder.  I find it handy to have a printout of the pertinent angles handy for just such purposes,  for setting the bevel gauge, the miter saw, and just to have a piece of paper for jotting notes on:

 Now that I've located the shoulder line, I mark it on the top of the plane.  Using a marking gauge, I mark the left and right sides of the wedge pocket.  You should have 1/4" of bearing surface in the shoulder, and 1/4" of wood left on the outside of the shoulder.  The finished width of the wedge pocket will be about 1/16" wider than the iron being used.  This is the weakest part of the plane, and thinner than that risks breakage during heavy use.

Carrying the same line forward to the line of the upper throat front (the angled lines shown in the top photo), I also mark out the lines for the cheeks.  A marking knife is handy here, and darken the lines with a pencil so you can see them.

Using the keyhole saw I made in another article I saw out the front and back lines of the wedge pocket, staying about 1/16" shy of going to the complete depth.  This is to help avoid tearout when chiseling it out, or at least give me enough depth that I can float it out if I get some:

I'm way happy with this saw - this is the express purpose I built it for, after the experiences I had with the original, where I used a Zona razor saw with less than stellar results.  It also shows that I didn't do chip carving on this side of the handle.  Why not you might ask?  That seems to be the question on everyone's mind, because everybody - and I mean everybody - asks me.  Well... I'm not telling.  It's one of those mysteries you all will have to live with!

 From there, it's over to the bench where I've got a clamping set up for chiseling out the throat:

I've found that these situations call for an old fashioned paring chisel.  Those are very long chisels, sharpened to a very fine point (like 20 degrees) and are intended for hand use only, no mallets (even though you do see one in the photo, it didn't get used with my precious paring chisel).  The length of the chisel give you an added amount of control not afforded by shorter chisels that I think is all the difference in the world.  You are really cheating yourself if you don't have at least one good paring chisel.

When it's as deep as I can get it, I work from the other side with a 1/8" chisel.  Someone asked once what such a small chisel is good for - this is one place where nothing else will work.  You do have to be careful that you don't either damage the mouth or chisel it out too deeply:

Like I said, I try to work to within 1/8" to 1/16" or so of finished depth.  The rest will be removed with floats (which to me have proven indispensable for these projects). The same is true for much of the plane - I'm working a bit over finished thickness, so I can joint/pare/sand/file/float it smooth when the work is done.