hello welcome to Enots engineering in this week's episode we'll continue
making the drill grinding fixture this week we're making the base plate.
this is the base plate this one's made out of aluminium but it needn't be made out of
aluminium It can be steel. Involves some faceplate work machining the radius and
a bevel marking the zero position and also thinning out some of this material
so let's go to the workshop and see how we did it.
I've marked the center line positions of the holes that I want to drill.
they're there and they're I've put it on center I've zeroed my table to that
position because that's going to be the dowel hole so all the other holes will
be marked from there
I've got an offcut of MDF I've drawn a line down marked the position of a hole
drill the hole and I found this screw which will fit in there that being the
Datum hole that I'm using so I'll just screw this onto there doesn't need to be tight.
I'm just using that as a pivot point so now I'll set my bock let's clamp it up
there's the center line there bring that in front of the blade just check that
the teeth come up to it. Lock up the piece of wood now I've got a pivot point
there so I'm going to switch the saw on and see if I can cut through that
I've just put this piece of MDF in the chuck jaw. I wont to make a bung that goes in the
center of my face plate with a 5mm hole through. Just touch it on to the job
Wind it in and it trues the part up so now I can just nip that up
And the parts running true and all this is is a bar with a small bearing pressed
on the end you bring that in the bearing touches the job taps it true
the only thing you don't do is tighten the chuck up fully you just grip it lightly true it
up and then tighten the chuck up.
that's coming out thirty three point nine
nearly thirty four I think I just need it just under thirty three
33 that will do just face it off so I know it's square
what I've done with this base plate is put a 5mm peg in there that's the
5mm hole I've just tapped it into the centre so when that goes in that
gives me a lineup now what I need to do is put some clamps on the outside so I
can turn this radius true and put a bevel on there and mark up the center line
This is how I've bolted this down to the faceplate.
what I'm going to do is machine the outside of this with a chamfer on
but I want to reduce this flat surface area by five millimeters
so I'm hoping I can turn this at the same time
this piece is clamped with the two
triangles and this here is a piece of packing just to get the same height
and at the back there's a piece of packing so I'm Bearing in mind that when this is
going around that if this comes loose these two pieces could fly out
the center piece won't because it's held in with the dowel in the center and these
are held in with nuts also that the component is up against this bolt so
that as the tool as this comes around and the tools cutting that way any
forces pushed up against that bolt so it won't turn.
now I fitted the faceplate the first thing I need to do is mark the centre so I can then measure the diameter
that I'm turning what I want to do is turn this diameter on the outside
down to the correct size which is 118 mm from the centre
Put my tail stock in with the center drill in I've move my saddle across
I'm just checking that the the part doesn't hit the saddle which is clear.
It's all out of the way
It doesn't need a deep hole it's just to mark the center and what I've done is
I've had to change this plate that was here was a smaller plate was that plate
because this end there was a gap underneath it wasn't pulling down so
what I want to do first is machine this down to 5mm thick that area there
and then machine the rest down to the right diameter and put a bevel on there
I've checked that the tool is going to be clear of these clamps that's the
furthest I want to go in at that point that clears everything
So the next thing I need to do is change the clamp and then machine off 5mm off his face
that's that I've fitted a screw cutting tool sidewards in the tool holder.
I've zeroed the tool level with this line that I marked before moved it to the edge and using
the compound slide just go in and score the line down the side there to be a
zero mark there.
so that's finished we've machined it to diameter here put the chamfer on there
at 30 degrees machine the face 5 mill lower because I need the space and that blocks finished
Now I'll bring you up to date the two 5mm holes that were in the base
I've just countersunk to accept a 5mm cap head. The spindle block I've drilled and
tapped to 5mm holes.
So this is the original tool holder with the cutter grinder.
I'm taking that off and this one will go on I need to put a 6mm
dowel in there which will fit in the hole there.
That will fit about there so it
can swivel with the degrees each side the plate will tilt up and down for the
angle of the cutting edge locking screws fits in there
that's the locking screw from the existing fixture just put the spindle lock there.
and we also need to make the spindle so the next thing we need to make is a 6 mm pin
piece of silver steel in the chuck it's about 8mm I need to
bring this down to 6mm to make the dowel for the location pin
0.265"
0.237" a thou over I'll leave it at that.
and before I part that right off I want to put a chamfer on so that I can tap
it into the hole
And thats the 6mm dowel I'll fit that in the fixture there's a 6mm dowel fitted
That locates on the table on the cutter grinder
you've also machine this radius on here and put the zero position there with
that mark so this will match up with the angle on the table.
we've counter sunk the two holes underneath so that they're flat with the surface so that can sit flat
And these two holes come up inside the bore into the cutout that we machined so
that the burr on the inside doesn't affect the spindle bore.
I'm just planning out how to machine the spindle without having too many change overs so
I've decided to cut it between centers that way I can machine the thread and
the spindle diameter in one operation between centers without having to change anything.
So the first job will be to machine the face centre drill it
drill the bore out with the drill and then recut a cone for a center and on
this end turn it around in the chuck face it off and to drill each drill this
bore out with a drill and recut a cone for the center
oh well that's it for today I'll start making a spindle on the next episode of
Enots engineering