Beginners Guide to Manual & CNC Machining!

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hi folks welcome to another episode of

NYC CNC this video is for the Concord

kids they're a group of students that

are focused on the stem curriculum and

their advisor shot me an email and said

some of the stuff that they're working

on it would be really helpful and they

had a video that would show them some of

the basics of what a milling machine

does and this really struck a nerve with

me because coincidentally I was just

talking to a local Ohio area overview

and he's a he's responsible for all of

the trades curriculums and they have a

huge interest in the welding program

it can't get kids interested in

machining which baffles me and I think

part of it is because welding is big in

Central Ohio with a lot of the oil and

gas and people think if there are

welders they get to drive big trucks and

get muddy and go to job sites and hey

that's that's cool to people I totally

get it but but to think that they're

choosing that because they don't even

know what machining is like they have no

idea and hey I was there once too I

didn't grow up my grandfather was a

steel fabricator I didn't grow up with

Bridgeport's and milling machines and so

forth so I get it so I would love to

make this little video and show people

what metal cutting and machining is what

I want to do today two really basic

things we're going to show some test

cuts on a piece of aluminum with a

Bridgeport milling machine this mill is

probably 50 years old but it runs great

and then what we'll do is we'll move

over and we'll take similar type of cuts

on the tormach CNC machine which is a

computerized version of basically the

same thing this is our Bridgeport

milling machine it's kind of like a

drill press but a lot more it's similar

to a drill press and that we've got a

handle that raises and lowers a tool in

the quilt but if you'll notice this

quill is really fat and it's actually

really strong compared to a bench top

drill press but what makes the machine

really different from say just a drill

press is we've got these handles I can

rotate these handles and move the table

left to right or the x-axis and then I

can use this handle in the front here

and move the table back and forth or

front to back in the y-axis

so not only can we cut down like you do

with a drill bit but we can use an end

mill just like that's in here right now

and cut on the side of a piece of solid

metal just like that there's a ton more

this machine you can actually do but

that's really the essence of what we

need it to do and that's what we're

going to take a look at today so not

only does the machine have to be really

strong and really rigid but to be useful

it's got to be accurate accuracy is just

key and metalworking and machining and

for this machine which remember it's

like fifty years old we can still do

that the key are the graduated dials on

the handles we can use these dials to

accurately machine and measure distances

in 1000 of an Inc increment measurement

and if that doesn't sound precise to you

a thousandth of an inch that's crazy

a sheet of printer paper is four

thousandths of an inch let's take a look

at that accuracy our dial here is on

zero we'll go ahead and rotate it I'll

do it slowly for the camera to twenty

thousands so that's about five sheets of

paper that we should be moving the

machine in enough talking let's see this

thing in action safety glasses on folks

what we'll do it we'll slide the

workpiece under our end mill we're going

to use a two flute pretty large diameter

end mill and we'll just go ahead and

move the quill down still right on top

of the workpiece that locks the quill in


I'll come off the workpiece and I can

actually lift the table up just a hair

we'll turn her on and let's see if we

can face off the top of this part

so nice and easy we'll come over and you

should see we're making a nice chip

machine doesn't sound too loud and

because this workpiece is out a little

bit of an angle we'll probably run out

as you see right there so okay we'll

come back and we'll just keep cleaning

it up you go a little faster if you want

again folks we're cutting through metal

right now I think it's pretty cool

you want to try to be smooth with your

motion that will make for a better cut

back right over here looks like that's

all we'll get removed at this height if

you will we'll stop the machine and if

you feel that it is silky smooth and

that's what's really cool it's a really

nice quality cut so that was cool we

sort of cut the top of it let's see if

we can do a little bit of a heavier cut

and let's actually see if we can measure

the accuracy so we're going to unlock

the quill lower the tool down and now

what we're going to do is we're going to

take a little bit of a cut off this one

side then we'll use our dials and our

digital readout to measure how far over

we cut and let's see we measure the part

that we end up with and see if we were

accurate so here we go fire up

pretty cool you can see the chips flying

off that machine should be a nice

surface finish it sounds good you don't

hear chatter real nice cut nice and


let's take a look at that beautiful I

like that let's take a side cut now and

see if we can clean up the side of this

part and then move over we'll measure

how far we move and we'll see if that

distance makes sense and is accurate

this is a two flute quarter inch end

mill let's fire up

nice and smooth

look at that great surface finish very

happy with that now we'll come back and

we cut that at zero on our dial so let's

move all the way over

and if we cut it

at 2:00 we'll see if that makes sense

now that's a little bit too much for me

to take in one pass so well lift up the

quill and we'll take a little bit of a

shallower pass it first and we'll do a

few more deeper nice and easy

come down a little more

you could also come up with the knee

either way works

so let's use our digital calipers sort

of like a tape measure but pretty

accurate let's see what we got going to

fit them in here where it we're at 1.75

inches so let's think here does that

make sense well at first you would think

no I thought we went from 0 to 2 inches

but if you think about it when we were

cutting on the left side we were at 0

but remember we're using a quarter-inch

n-ville so how is ear o is the center

line in the middle of the tool so it was

cutting 1/8 of an inch or 0.125 off on

the left then we moved over to the right

we cut another 1/4 1/8 of an inch or

0.125 so in the end we've removed point

two five so we went from zero to two but

we back out that tool diameter 1.75

Fulks pretty cool huh

here is a CNC milling machine believe it

or not it's actually incredibly similar

to the Bridgeport we just use the

difference is that instead of using a

hand and cranking those knobs

we've got motors and they're driven by

computers which take G code that we sort

of program in and it's those computer

computerised motors that move the

machine back and forth which is really

cool because you can end up with a very

easy way to automate the cutting as well

as create complex cuts and if you want

to watch a really good video in my

opinion on basic way to build and

understand I just did one where I use an

Arduino and a very inexpensive shield

called a garble shield and we built from

nothing a pen plotter that we use to use

a pen and create a pattern it's pretty

cool stuff folks and it's really not

expensive to get into so this machine

again it's just like the Bridgeport

underneath here we've got screws and

motors and that drive the table back and

forth and we can use the computer

keyboard we can go left and go right you

go backward and away from us and we can

go down so we can come back up that was

me controlling it myself I've got a

little program in here and what it's

going to do is it's going to trim this

block sort of like what the Bridgeport

did and we'll measure it afterwards and

see what it looks like

and then it's also going to create a

circular pattern in the middle and

that's something that would be a lot

harder to do if you didn't have a

machine they could calculate and control

the steppers with such precision

okay so there's spindle starts up and

proaches the side of the part here

you'll hear the coolant kick on those

two gray lines have coolant and you

notice when it didn't just jab itself

into the park or the nice smooth ramp in

coming along you can see the chips

flying off looks really nice the reason

that end moles coated is it's a special

coating different coatings for different

materials that help improve the cut fall

on your tool life lots of really cool

things like that again though it's all

being driven by the computer here and

the motors that you see under that are

underneath this machine should be pretty

darn accurate the proof will be in the

pudding we'll have to measure it here

when it's done just about coming out

home stretching if you watch closely

again it's going to ramp out and take a

nice little curve right about now which

hopefully will mean there's no tool mark

where the heart started finished now

we're going to cut a circle and instead

of plunging straight down into it you'll

notice it did a little it's called an

interpolation but think of it like a ass

like a curlicue type of slide and that

really reduces the chip load or it's a

lot easier on the

the tool nice and easy going into the

part like that and if you think about it

it's cut in a circle like this is using

using both the X and the y-axis at the

same time and that's what's led us cut a

perfect circle like this which again is

something there would be a lot harder to

do on the Bridgeport

but is quite easy on a CNC

there we have it let's grab our calipers

and let's see if we really got what we

hope here look at that folks

2.2 4 9 we're about 1,000 under so

across that whole distance or less than

1/4 the thickness of a piece of paper

off I'll take that any day folks I hope

everybody enjoyed that really brief

episode of NYC CNC and sort of basics on

both manual and how a CNC machine works

for those of you regular subscribers I

know this was really basic but I'm

really hoping to help and encourage

anyone involved with stem or any sort of

youth engineering and Science and

Technology it really is so cool I would

encourage you to reach out to either

your local STEM program or FIRST

Robotics or anything you can do because

I tell you the world needs more

engineers and scientists and metal

workers and stuff like that to the

conquer kids I hope you enjoyed this

video I hope it helped you learn and

understand the types of equipment out

there a lot of it isn't expensive

anymore that's what's really cool I did

a video about buying this Bridgeport

which I bought for less than $2,000 I

know that sounds like a lot but it also

produces money it's not a huge

investment some really cool

opportunities out there I certainly love

being a machinist in being able what I

being able to do what I love in this

career and field and the more we can

help people understand and see what's

out there and enable them the better off

we are

so thanks for watching I'll see you this

Wednesday for the Wednesday widget

otherwise take care see you soon thanks