The Saw Sharpening Rake and Fleam Angle Jig

I love simple solutions.  I don't recall where I first saw this jig, but it's not my own design.  I wish I could give proper credit because it's so simple and works so well.

Square up a small block of hard wood (soft woods will get worn out too quickly) about 3" long, 1" wide and 1/2" thick.  Knife a line to locate the lengthwise center of the block.

Line knifed in center of block

Drill a hole of appropriate size so that the file you intend to use will fit tightly in the hole.  The file should only go about 1/4" into the hole.  Most saw files are tapered at the end, so this works well.  I drill from both sides so the holes meet in the middle.

Mark the rake angle of your choice on the side of the block next to the hole, as shown above.  One line would have sufficed - not sure why I drew 3 lines.  Write the angle on the block for future reference.  Then line up one side of the saw file with that angle and tap it in.  This will leave three little indentations around the hole's edge that you can use later to repeatably place the file at the proper angle.

Using a ruler to get the angle right

The saw file sides are very small and it's tough to get the angle right.  But if you hold a ruler flat to the side of the file, then you can sight down the file to see that the ruler is lined up with the angle you drew on the block.

When a file in installed and you hold the block level, then the one side of the file will be held at the proper rake angle, in my case, 14°

For the fleam angle, mark and then cut the angle on the right side of the block.

Angle marked ...

... then cut and planed smooth (and the angle penciled on the side) 

In use, the jig is used as in the picture below.

Saw file held at 14° rake when block is level,
20° fleam when angle on right of block is parallel with saw

There is one very important thing to note about using the jig.  After filing every other tooth of a cross-cut saw, when you turn the saw around to file the remaining teeth you have to remember to turn the jig around.

Orientation of jig when filing saw with handle (H) on left

Orientation after turning saw around with handle (H) on right

Note that the rake angle marked on either side leans toward the handle (H) end.  It's important to get this right.  I've marked the top of the jig, as it stays the top no matter which way you are filing.

Also, I've written which file that I used with this jig since the hole is sized for that particular file.  I have a few of these jigs - one for each size file that I've used.

BTW, if you want to use a jig like this for filing a rip saw, just leave out the cutting of the arrow-point on one end and make the rake angle appropriate for a rip saw.