I still need to make a top for this block.
So that's next.
So, I'm just using the dimensions
here and a set of calipers to
transfer where all the holes need to go on this thing.
So, I've just drilled the holes for my markings and now
just gonna put 2 bolts in here and clamp that
down to make sure I've got the alignment right
and that everything's parallel.
Now to punch through where to put the screw holes.
So, now let's screw that on here with the pilot holes
drilled.
Here I'm cutting out a big 48-tooth gear.
I have a whole video on how to make gears
So I'm just going over this one relatively quickly.
Notice how I tilted the table for cutting the sides of the
teeth. That gives all the teeth a bevel which makes them
ride much better against the right angle of the other gear.
So that gear already turns pretty good.
But it also really helps to make this slippery.
You can do that by putting varnish on there,
Or by putting some UHMW tape on there.
Which is this tape that comes in these 2 layers.
I've already done that in the gear mount for my other
box joint jig. This one I'm gonna
leave it as it is right now
because it doesn't make sense to put the tape on
before I put varnish on it.
So this gear mount is in just the right height for
engaging the 12-tooth gear, back here.
But to engage the 16-tooth, this needs to be
raised up a little bit and this is what this slot is for.
So I'm just gonna mark on here where that 1 slot
needs to be. And I know the other slot needs to be
11 millimeters further down.
I actually need to make a cut that's a bit wider than
my saw blade. So I'm just gonna move that fence by
about 20 thou, and then make another cut.
So, now with this tab in place, with this gear mount in
the lower position, it's lined up for meshing with the
12-tooth gear. And now if I pull it away,
and engage it with the upper one,
it's now lined up for engaging with the 16-tooth gear.
Right now I get a 3 to 1 or I get a 3/16th inch
per turn and with the gear in the lower position,
against the 12-tooth, I now have a 4 to 1. So each
turn gives me 4 turns for one quarter inch.
So, depending on which gear I engage on here
and how many turns I put on per cut,
I can already get a lot of different spacings.
But for my other jig, I've actually already made
a large number of other gears, which allow me to
create just about any spacing that I want to
by varying the number of turns and which gear I'm
gonna engage it with.
Now to allow this jig to slide on the table saw,
it needs to have some sort of guide bar. And for that
I'm just using a solid piece of cold-rolled flat stock.
So, using my 1 to 1 print-out again, what's left of it,
I'm just gonna put the bar here.
That's about right. And I'll mark where the screws are
supposed to go.
I'm making some divots where I'm going to drill the hole
just to make sure the drill doesn't wander before I start
the hole.
I'm going to attach this flat bar using some number 10
machine screws, like one of these.
And here's the tap for cutting that thread.
And the to check that that's correct is to make sure
it engages. So that gives me extra
confidence this is the correct size tap.
Now to drill the hole for this, the ideal size actually is
slightly in between drill.
But I'm gonna use one of these, a 9/64th.
And I can tell that's a good size because if I hold that
in front of the screw, I can see the tread protruding
on both sides. So that I know if I drill a hole like this,
and then cut it, that screw will still engage.
And I'm not gonna be cutting too deep with this thing
because these guys are really easy to break.
It helps to put a drop of oil in the hole before cutting
the thread. And I'm always having a hard time
starting this at the right angle, so I made a little guide
block to help me start it at exactly perpendicular.
You may not be able to do this in one go.
Sometimes you have to back out a few times.
Be very careful. It's very easy to break these.
The first time you're gonna use one you'll probably
break it. So the next thing I need to work out
is where to put the guide bar on this jig.
It's not marked in the plans where to put it because
the distance between the blade
and the bar slot is not the same on every table saw.
So I start by squaring it up with using a miter gauge.
And with this carriage cranked all the way to the left
I want the saw blade to be just right
this blade is just right of this part here.
So that the first cut I can actually hide the blade
underneath here. And so having positioned it
like that, with the carriage run all the way left,
I now know that the guide bar needs to go here.
Now I can just use a framing square to make sure
I draw this line
exactly perpendicular.
So, here's my guide bar and I'm gonna use that to mark
the holes. I haven't actually drilled these entirely
accurately. So I want to make sure when I put this
back on here it'll be exactly the same way.
So, I'll mark and X on here just by scratching it in.
And I'll put that X on here as well.
And making X face the X.
I will always put it down this way.
Now checking the angle one more time
just to make sure.
And now I'm gonna use these holes to mark
through where the holes in the base need to be.
And I'm using the same drill that I used to drill the
pilot holes for this. So I know that fits exactly in here.
And by tapping it, I'll just produce a divot right at the
middle of this hole.
I'm just gonna deepen those divots a bit
to make them easier to hit.
And now using my 9/64th drill again,
that will be a little bit tight for those screws,
But I actually want them tight. And it's tough
to get this exactly the right angle, so...
I'm using this block of wood with a V in it just to help
me get that hole started.
Now I need to put a counter-sync in from the top.
And ideally I'd use a counter-sync bit on here.
Unfortunately I don't have enough room to work here
and I don't want to take the whole jig apart.
So I'm just gonna use a long drill bit
and drill very carefully.
Now it's the metal bar again, my X is here.
And here's the other X. So I know that bar goes
exactly like that.
And the holes, no matter how inaccurately I drilled them,
should line up. So I can now start screwing this bar
back on.
Well, I goofed up a little bit. What happened is when I
counter-sunk these screws in here,
they actually came out the other side of the bar.
So, rather than cut off my screws, I just put a washer
beneath them. So that means they stick out the top
but that's actually much less of a problem
because with this jig,
the way the screws are positioned,
both of those screws are actually underneath this
part and that part of the carriage.
So they're not going to interfere with the stock that
slides back and forth.
So I still need a handle for my jig.
Of course I could buy a handle at a hardware store
but that can easily run 4/5 dollars.
So why not save a few bucks and make one out of wood.
I'm using the templates from the plans for making this one.
So, now for the placement of this handle,
easy enough with the carriage run all the way left.
It has to not interfere with the idler roller. So I can just
put that right here.
Well, this jig is almost complete.
There's just 1 more step to be done and that's
to cut a slot in the base.
And now it's done.