Hello welcome to Enots engineering I'm Alan
this week we finished off making the indexing head for the lathe
and I had a problem when I was making the holes in the indexing ring
the chuck came loose on the rotary head and some of the holes were out of position
so I have to remove the holes and start again
but luckily everything turned out all right in the end
so let's go into the workshop and see how we do it
we're making the knob and the thread that goes into the back of this
where the plunger goes in
this will have its m6 thread on this will have an m8 thread on
the next thing I've got to do is machine a knurl onto this
put the threads on and then part it off
I've just set my knurling tool up put the speed on slow
feeding in with the the top slide
that's okay that'll be okay for what I want
I don't want it too sharp I just want to be able to get a grip of the bar
I'll change back now to my partying off tool
but before I part it off I'll cut the threads
now we'll change the die for a 6mm die
now because I'm getting a lot of vibration it's easier to saw the last part off
I'm holding the part in a ER20 collet
so now what I'll do is set my radius cutter up to form a radius on this end
I've just set the tool roughly in the middle and whatever radius that is looks
as if it will be okay for that
I will back this out a bit
I've checked underneath everything's clear
put a filel on the very edge where the knurl is because it's just a rough edge
so it takes the rough edge off and I think that is finished
so we've got a dome on the back a knurl and two threads
the size of the tap the electric drill has to put too much force on
the 8mm thread that screws in okay
put the plunger and the spring in theres the spring and the plunger
now the end of the plunger needs a couple ofspanner flats so we'll do that next
you can see if I tighten this the plunger moves forward
you can slide it across
I can put a row of holes in here in this disk
and then the plunger should go I haven't tighten it up tight
the plunger should go down enough which it does on there
It's touching the chuck at the moment but the
hole will be shallower than that so it will grip into the hole to locate
and just turn it to undo it I've done away with the spring
the spring I had there wasn't enough tension in the spring to push the plunger out
you see the plungers slides in and out it doesn't need the spring really
so it will slide out to that far so you can move whatever you want as you push it in
It will start to tighten up on this screw it feeds the plunger forward
I had to put those two flats on so I could get the spanner on
so I could tighten it up on the end of the shaft but you can see there
if that was a hole with a countersink in here that would easily do it
I may have to shorten the end of the plunger but I'll do that in the lathe
Just run a file over the end but I won't do that until you see that's free enough in there
so this screw screws into the back of the plunger until it locks up
and you just have to adjust it to give you the length that you need
Now the next job is to mark out the position of the rings on the outside
what I need to know is
where can I put the first row of holes
I've just painted some marking out blue on the edge of the indexing ring
and then I'm going to use this plunger just to rub across mark the line
I've just switched my computer on it's running XP Windows XP
the program I've loaded is Mach 3 this programs used to run the CNC machine
and all I'm running at the moment is my indexing head the electronic indexing head
Thats this reading here which I can zero
this is in degrees 360 degrees
so all I do here is feed in the amount of want to move
and this will move round that amount
I've not used this indexing fixture before
so what I want to check is the accuracy on the rotation
So I've zeroed my dial indicator on this jaw face
pull the dial indicator out still set at zero
and now I'll rotate that 360 degrees
That should move
It should stop when the jaw gets back to the top
Thats better move across that's on zero
what I don't want to do is drill through here into the chuck
so I'm just going to use a feeler gauge under there
to feel when it's coming through
I've set the speed to 1000 RPM
and just have a look how that goes
now at that depth the drill has just come through and it's 0.010" from hitting the chuck
let's have a look at depth I think that's deep enough on there for a countersink
for the plunger to line up on
so if I slacken off the clamp and then index it
I want to put 24 holes around there so I will just index itI to the first position
and see what the gap is between the holes
so I need to move 15 degrees
that's the spacing
so I'll lock that up there and drill the next hole
move to the next position
as you see this is the finished indexing ring
will confess I've had to reduce the width of the ring
because the first row of holes l put in unknown to me
the chuck had come loose on the indexing head and the last few holes
were about a eight to an inch out of line and there's there's nothing
once you've got them out of line there's nothing you can do
so what I've done is machine it off
and redone another set of holes making sure that the chuck was really tight on the indexing head
when I'm using this indexing head it's best if you use it with the back gear in neutral as it were
here between the two gears
because once you select the right position you can spin the truck easier
plus the interlock will stop you putting the power on when you've got the pin in
so the way it works is, I will have to number these up as well I suppose
you just start wherever you want to start tighten up the pin and you can see the
pin goes in till it locks
and I've just checked the one and there was still some gap at the back
check this one yeah it's not touching on the chuck it's touching on the countersunk part
so that's locked the chuck up solid
so you do your machining in with you your tool post drill or whatever you want to do
and then you decide to move to the next position
so you just unscrew this
what I would do is probably use some of these felt tip pens that you can mark the positions
there are twenty-four holes so that will give me a combination of
I can do the two side a three sided four six eight or twelve
so if you wanted to do four you have to move it six holes
so this one two three four five six come round to there
put the pin back in
lock solid machine will if you want
mark the chuck
undo the pin
one two three four five six
put the pin in locks mark that chuck there
these pens are white board pens so you can rub the marks off
do your machining and then come out to the next one with
twenty-four holes they have seven combinations of different hole patterns
if I had machined twelve holes
I would have five combinations of different hole patterns
so depending on how many holes should put on your indexing ring
and of course if there were twelve there'd be quite a big gap between the holes
so you could have probably put another maybe gone up to 36
and that would have given me eight different combinations
but the main ones you want are probably going to be divided by two or three if you put the flats on something
to hold in a Jacobs Chuck,
four if you want to make a square six or eight hexagon or even 12 or 24
I'm annoyed that the chuck came loose on the milling machine
but you learn from your mistakes it won't happen again
all in all I think that's it's made a nice neat job
used something that was scrap
and if I need an odd number of holes for something I've still got room
on the side here to put another set of holes in
and to do that you just unscrew the pin
unlock
move it along to wherever the holes are
and do it back up again
well that's it for today thanks for watching
I hope you enjoyed it hope that's useful
and if you liked it why not subscribe
look after yourself and we'll see you next time on Enots engineering