Thursday, July 31, 2014

Travisher Blade Grinding Jig

Alright ladies and gents the mystery that is 'grinding a travisher blade'  will be exposed in one simple jig.

To get started take a trip to your scrap bin, because lets be honest if you are reading a woodworking blog you definitely have an embarrassingly overflowing shelf of cutoff's that repeatedly gets added to with the mantra of "someday i'm gonna need this". Well that someday is today. So get on in there and grab any ol' piece of hardwood and cut it down to 5"long X 21/2"wide and the thickness can vary anywhere between 1" to 13/8"

Now if you got a ding in your blade or its's just plain dull, you would, just like any chisel or plane blade, joint it first on your stones. However! jointing a travisher blade (pardon my excitement but this is the only time I will get to say this) is much easier then any chisel or plane blade, because it's curve keeps the blade from tipping every which way. And another plus, eliminating the dreaded nails on a chalk board sound. 

Once the blade is joined you are going to trace the back of the blade profile onto your blank. Its important to make sure the blade is joined before the tracing is done. As you can see my fingers are right on those corners so best not to have a sharp edge while handling a blade like this.

Got your line. Got your offcut. To the bandsaw.


And you should end up with something like this

When attaching the blade it is important the edge of the blade is parallel with the bottom of the jig. The bottom face of the jig will be your reference when setting up the grinding angle. To make sure of this I clamp the blade to the jig with 2 clamps (knowing that the top and bottom faces of the jig are parallel to each other) I eyeball a 1/16" gap down from the top face of the jig on each side. So you can easily see a 1/16" ledge from the top edge of your blade to the top of your jig.  And if it were to slide a bit after you screw in one side, no worries, just match that ledge clearance on the other side. 

After you've clamped the blade up into its proper position I like to make an indentation with an awl to mark dead center on the hole, this helps to prevent the blade from moving when I screw it on. When you come in with the awl, keep in mind you wont be holding the tool  vertical. You want to angle it so it is square to the tangent of the blade.

And end up with this

With the clamps still on I will come in with with my drill at the same angle used with the awl (square to the tangent of the blade) and fasten it on. I use 1/2" #6 screws, #8 will work. But, its best to start small this way if your holes start stripping you can move to a larger screw. I like to secure down one side then the next, this way I can account for any movement in the process.

And here you have it! The Travisher Blade Grinding Jig you've never dreamed of.  Welp, unfortunately that is all the information my ADD riddled mind can spurt out in one sitting.  I promise I wont leave you hanging for months on end, stay tuned and I will take it to the grinding wheel.














5 comments:

  1. Take it to the grinding wheel! Take it to the grinding wheel ! The suspense is killing me….

    ReplyDelete
    Replies
    1. Rundell, you can relax now, took it to the wheel and beyond!

      Delete
  2. Does "joined" mean 'jointed'? As in a jointer plane that flattens a board edge? Woodworking terminology can be thick as brambles, so I want to be sure.

    ReplyDelete
    Replies
    1. Bruce, yes, jointed it is, sorry for the confusion.

      Delete
  3. Great article! Thanks for sharing...

    Floor

    ReplyDelete