In part 1 I prepared all the materials and started assembling
the base for this tenon jig.
These 2 blocks are gonna support the carriage that goes on top of here
and that carriage has got a base
and a front face
and this brace here and
screwing all those together is a bit tricky
so I'm gonna do this off of here
and I'm gonna use another piece of wood
to jig this together with.
And this goes flush with the back edge here.
now I just clamp these blocks in place to make sure
this is gonna go in the right position
so I can drill those holes through.
Now I can put this part that’s called the E-Fulcrum on the bottom.
And this is ...by this pin is what the sled is moved back and forth by.
So I gotta center that over the holes.
And clamp that in place.
And now I can drill the pilot holes through here.
Except I don't have quite enough room to drill straight down here.
So lets transfer the location of those holes.
Thanks.
Lets just make sure the shaft is gonna fit where its supposed to
with these blocks all holding it correctly.
That looks good. So now I can screw these on.
With these 3 blocks now screwed down
the alignment isn't quite perfect so that shaft is actually quite stuck.
But that's a good thing because that means I don't have to worry about it sliding.
It's not supposed to slide in these holes.
I added some small screws here and here to make sure
those bushings don't work their way out.
And before I put the sled on top of here
I have to make sure that this lever mechanism
all works correctly. 'Cause I can't get it afterwords.
So that's nice and tight. No play and now the one back here.
Need a spacer underneath here to make sure I don't bend it.
So that's working good.
Now the lever actually needs to attach to the E-Fulcrum down here.
And that's what this hole up here is for.
So I can insert the pin from the top.
Now just checking that I've got enough range of motion
around the shaft here.
And now I can put this together.
And getting this shaft in is the least fun part of building this jig.
'Cause its gotta go through in here all the holes
and especially the last hole. It gets very tight.
Now this jig still doesn't have very much guidance in this direction
which is where a couple of rails on the front here come in.
And I have to cut this one to be the exact right thickness
to put this on here level.
So this needs to be
the same height to be flush on the back here.
So, let's mark that.
So the way this works is with this rail screwed on top of here.
That prevents it from tipping forward because now this rail
pushes against there.
And to keep the jig from tipping backwards
this way, there's another piece that goes on top of there
that locks it in that way.
With the jig assembled I can now check that it that it's square.
And I can see here this wiggles just a tiny bit
which means that whole thing needs to go this way a little bit.
And I'll cut that down in thickness a little bit.
And in this direction let's see.
So it needs to come this way a little bit.
And I've played around with the square on this already a bit
and it appears this angle in here is not quite square.
So I'm gonna re trim this part
and mount it back on.
Next I need to make the stop-locks here.
And last time I cut them with a slot mortiser
but this time I'm gonna be lazy and I'm just gonna cut these open.
And then cut them out with a band saw.
I always use a clamp to hold the stock in place on the jig.
But I'm always afraid that as I cut through here
this clamp might come loose and fall down onto the blade.
So this hook is there to prevent that clamp from falling off.
The hook goes right about here.
So I'm just gonna mark where the pilot holes need to go.
For accurately indicating the lateral position on here
you can mount a caliper on here preferably a dial caliper
and with the bar fixed onto here and this jaw attached here
so that as this moves
the caliper will indicate the position.
But I very much prefer using a dial indicator.
And that dial indicator screws right onto here.
And you should ideally use one with a 1 inch travel
just so you don't run out of travel really quickly.
So next we need a stop for this dial indicator to reference against.
And that's tricky to mount.
The block clamps on here
by being attached with a screw diagonally through here so as that screw is tightened
it clamps it up together here.
But drilling that hole is tricky so I'm gonna put a spacer in here.
And now clamp that on very tightly.
And now with both pieces on here I can try to drill through here
roughly like so.
So I need to enter about here.
Right here.
Let's make the shank hole a bit bigger.
And add a counter sink.
And let's put the screw in and see how that goes.
Ok, that did require a little bit of tweaking
but I can now move it and clamp it.
Now you might be wondering what was this guide bar slot that I cut early on.
Well I figured the whole jig would be much easier to work with
if it was flat on the bottom.
But now that it's done I could add that.
Depending on how easily the carriage slides on the rod
and the stiffness of the wood that you used for the linkage
this can be quite repeatable. So, let's see.
Zero.
I think it looks a little bit better with some paint on it.
And I'm ready to cut my first tenon.
But the cool thing about the jig is not the speed.
But the accuracy and repeatability of it.
If you'd like to build this jig I have a detailed set of plans for sale.
These include lots of CAD drawings on how the jig goes together
All the templates that I used in this build.
A printable set of building instructions.
As well as the CAD model.
So just click on the links in the description.