hello welcome to Enots engineering i'm Alan well we're still on lockdown and this
week i think my brother's had his milling machine three months and he sent me an update on all the
modifications he's made to it since he's had it So let's go into his workshop and see how he did it
first rework is i've had to increase the diameter of this
this knob that engages the clutch which engages the feed
on there so i've had to make a new roll this knob that used to be this size and i could
just couldn't get the grip so we'd be slipping on on this control so i'm thinking i'm putting feed
on where i'm not actually putting any feed on so i'll just remove that so you can see
so it's just mainly a larger diameter so i've made a new handle
recessed it utilized the thrust bearing just to to allow them to put more load on
to engage the clutch so this is a clutch part of the system just a looks like a foster bronze taper
that's to engage in this other half it's pretty standard for these machines the spring in there
so let's re position that again so it's on the keyway
so it just takes a much less effort to engage that in a positive way
whereas the original knob i just couldn't get the power on there to be comfortable that it's
engaged properly without any slip on the front of the machine i've removed the original plate
and just the digital reader so that's part of that because i'm print
a dro system only with glass scales which is what this part is the glass scale
what i've decided to do is i've got a block of aluminium behind that
that utilizes the original fixings for this dro
with this one so i've not drilled the machine or altered it in any way so i made this block that
bolts into the aluminium block that sits into the cavity where the dro used to locate then obviously
some threaded some metal all thread bar and made a new quill plate the quill plate
also houses the rod of the linear scale for the glass scale for the position of that
and i'm trying this system out which i've seen on youtube quite a few people have made one of
these just to see how that gets on as a quick location instead of winding the nut up and down
to the depth stock section so it will act as a depth stop and
lock it in at certain heights as well stop it returning if i didn't want to lock it on
the quill lock handle here this i've had to make longer to clear the glass scale
you can see some wires here which you just i'm just experimenting because i've got the light
mounted at the front because i find that they're always at the back
and cast a shadow so you need two and you've probably got two shadows casted but uh so i've
sort of just put it at the front not used in anger yet to see whether that's good location
it might need to come a bit further forward so just to increase the angle so that's going to be
tested out to see whether that's a good location and once i've i'm happy that that is location
for it i'll probably run these cables into a little tube so you'd actually see the cables now
work up inside here it's all low voltage there's no danger of electrocution from that system
for the quill plate i've made this out of some 20 millimeter flat aluminium
machined it in a rotary table
then cut a slot down with a clamping bolt to go through so that fits over this the lower
boss of the quill and as i've mentioned before that then gives me the capability of mounting
the depth stop thread and the rod to support the sensor head for the glass scale
for the machine we've got the glass scales mounted
for the dro as mentioned before how to extend the shaft on this locking pin to clear this
the this is a 15 mil diameter aluminum rod that's been flat machined on one side
to accommodate the clearance for the locking pin because it's all a bit tight around this area
and this the glass scale sensor to be mounted on as you can see that's moving up down there
that's just bolted with the recessed cap head bolt up from the bottom
back on the same side on the machine i've increased the height of this support bracket for
the control box it used to hit this with this unit here which poses a switch for the safety guard
as one of the safety features that'll switch the machine off unless your safety guards in
position obviously safety guards not in there at the moment but it just used to foul and hit
this you can only rotate it that far which may be enough anyway but it's just nice to go to move it
out the way when i get it back or something like that and just just to go have a wider
rotational i've also decided to make my own power traverse use using a motor that's
very similar to a wiper motor but it's got a higher ratio it's a 50 to 1 ratio i've made
a collar that screws onto this the original plate end plate so it screws in from the back
and everything's mounted on this collar so i have a sleeve that goes inside this collar
and an eccentric on this shaft here that goes into a slot that allows me to engage and disengage the
drive so obviously that's disengaged it pulls the unit back on this drive shaft i have to make a new
drive shaft with this motor with a square on the end it's i think it's 3 8 square for small sockets
so i've got a 5 8 socket on there that engages on a nut that's splined to the main shaft
and with this design no swarf's really going to get into the mechanism should be fairly
user friendly obviously in conjunction with this you have to have limit switches i've constructed
the box which i've got two micro switches built that are built into this box that
mount through the same two holes that holds the pointer so again no drilling or rework
to the machine itself i have noticed that the way i've designed it the switches are
in a position where dirt or swarf can get down the back and could actually stop the switch working so
i will revisit this i have made a little plastic sheet that goes over there to try
and limit the amount of swarf that'll go down there but realize that he is in a vulnerable
position so this will need redesigning and then the wires from there feed up the back parallel
to the the other scale linear scale to the control box okay moving underneath the swarf tray
i've mounted the power supply for the the feed the electric feed in here is
the stepper control motor electronics that varies the outputs it's a pulse width modulated system
there is the outputs to the motor obviously i've got mains power in power out to the motor
and cables that connect to the control box with just magnets on the back the recommend is
higher up in the convenient place or hold it and i can vary I can vary the speed in its direction
left or right on the control box i've got a power output which will power the dro readout
when that arrives also to mention that uh i've made a spring-loaded adjustable stop
that obviously engages with the microswitch to stop the traverse automatically
this is the advantage of the magnetic backing on this control panel or command it anywhere that's
convenient run the wires around the back so i don't get in the way of the cutting operation
and i can i can just work it from here and control control the speed feed speed and direction
so i'm just slacking that off i'll run it up to there close to the switch
so i can just show you how that works just a quick demonstration of it in operation
so we have a slow i find i can go this is a percentage by the way
with the pulse width modulation the percentage not actual speed of the motor so it'll run down
to about 15 16 and you can see that it's just turning very slowly and it will go up to 100
and that's this motor is 50 rpm that's it's maximum
now i don't know whether you could see in the shot the limit switch has been triggered automatically
and avoid it in such a way that obviously i can go back the other way so from 50 rpm
all the way down to about 16 i've not worked out what that is rpm wise
the z-axis is the quill movement so i've mounted the glass scale on
the turret part so it's a direct replacement for this read out that i've removed so so once my dro
arrives i'll actually replace that with a better system through the glass scale mounting on here
y axis i've used some angle aluminium mounted to the machine using two fixing bolts at each end
then i've got some more angle aluminium
that comes down at 90 degrees to this to mount the glass scales too so the glass scales
are bolted this way into these other plates then obviously the cover on the top of that
so the x-axis is mounted on the back of the table again some angle aluminium screwed with two cap
head bolts to the table and then the glass scales mounted to that i've used a cap head bolts that
hold this uh the glass scales to the table i've used i've decided to put a groove in there and use
a circlip on all of them just to hold the cover on it's always an awkward way of trying to figure out
how can i hold the cover on stop it drifting a bit so that's the method i've used
on the milling machine on all the scales well that's all the updates to the machine so far
hope that was useful hope you enjoyed it and we'll see you next time on Enots engineering