Stepper Motor

[watzmann]

Hi All ,

where to find stepper motors in Electrical devices ?

for exampe , can i find stpper motors in Printers or scanners?

Thanks

 

[bloody-orc]

most of the motors in printers\scanners\copymashines are STEPPER motors :wink:

 

[solidhelix]

my groupmates last semester dismantled a CD ROM DRIVE to get a stepper motor :?

 

[watzmann]

Thanks for your reply...and that's really a good new to kow that all this devices work with stepper motors.

i'll start searching in my stuff for the suitable Motor for my project.

my project is : CNC plotter

 

[Nigel Goodwin]

Thanks for your reply...and that's really a good new to kow that all this devices work with stepper motors.

i'll start searching in my stuff for the suitable Motor for my project.

my project is : CNC plotter

If you do a web search, there are a number of similar projects on the net!.

 

[watzmann]

yes i know there's a lot of similar projects.....but actually i decide to build it because i'll need it alot in my work .

if you have a link to nice project similar to mine .... just put it plz

 

[Nigel Goodwin]

Here's a site you might find useful?.

 

[watzmann]

Thanks for this nice Link .

but i have a problem in my design so i need your some help.

in my project i may need to install a Pencil so my CNC machine will draw lines and circuits or whatever the shape ....... but my problem now how to let the Pencil automatically change it's point.....i thought that i may use a "Rotring" pencil......but now i'm looking for a mechanism which can help in case this pencil ponit is broken or something like that........so i need a mechanism to feed the pencil always .

have any ideas.?

 

[Nigel Goodwin]

Thanks for this nice Link .

but i have a problem in my design so i need your some help.

in my project i may need to install a Pencil so my CNC machine will draw lines and circuits or whatever the shape ....... but my problem now how to let the Pencil automatically change it's point.....i thought that i may use a "Rotring" pencil......but now i'm looking for a mechanism which can help in case this pencil ponit is broken or something like that........so i need a mechanism to feed the pencil always .

have any ideas.?

Don't use a pencil! - use a fibre tipped pen, or even a ballpoint pen. I used to have an old Tandy printer/plotter that used four small ballpoint pens to write on rolls of paper. You can also buy special pens designed to be used in plotters.

 

[watzmann]

sorry but i couldn't understand your idea well.....have u any photo for this ball point pencil .

 

[Nigel Goodwin]

sorry but i couldn't understand your idea well.....have u any photo for this ball point pencil .

A common trade name is 'Biro' named after it's inventor Laslo Biro.

 

[Bondfire]

Hey watzmann,

Sorry i don't have any hints for you; but i'm working
on a similar project called CNC Milling Machine...instead
of a pencil, there's going to be a drill bit which will mill
shapes....lines are easy...but how will you draw arbitary shapes
like curves/arcs? i mean the software part....we have 2 turntables
one moving a x direction, the other in y while the bit remains stationary.
In your case..Is your pencil movable or is the base moving?
Whichever of the 2, how are you going to realise curves in terms of
the movement?

Plizz ur help
Thanks!

 

[watzmann]

Hey BondFire,

nice questions. .....you want to know how can my CNC draw curves and circles, actually this was my problem before and i searched for ideas to solve it but then i found there's no problem at all beacuse of the CNC software.

there's alot of software on the net for hobbyists.....so i can draw what i want my machine to draw then i send it to the Machine.
the problem is how will the machine do the curves and circles although it just have 2 Axis X&Y .... Actually this machine can do it easily because of the Stepper Motor and The CNC software .

for example if i have a circle.....the machine will go forward and make a Dot in the X Axis and then in the Y Axis and again make a dot ..... thats depneding on the stepper motor steps per degrees.

i wasn't sure that this idea is possible but i found similar project made by someone i know and i asked him ..... he gave some products of his machine on a wood and it was full of circles and curves .... it was looking so wounderful. so i think it's possible

i hope it will success this time with me too , but i'm not worry about this point because if it fails ( and that's improbable ) then i'll make some changes with the Pencil to draw circles.


tell me your opinion.

 

[Nigel Goodwin]

nice questions. .....you want to know how can my CNC draw curves and circles, actually this was my problem before and i searched for ideas to solve it but then i found there's no problem at all beacuse of the CNC software.

Exactly!.

The monitor you're looking at now can't draw curves and circles either!, yet you see them on screen?.

Just like your CNC plotter it draws everything with small right angle corners, but these are so small you can't see them - it's just the same with a CNC plotter - the software plots the required straight lines and right angle corners to give the appearance of a curve.

On a low resolution screen you can really see the actual shape, but on a high resolution device it's invisible.

 

[watzmann]

it's nice that you agree with me .

but problem now is the type of the pencil .......or i may use ink Pens ,
but really as for me i need it to be pencil line.....so i'll try several types to find a suitable one ....... hope it success :roll:

 

[Bondfire]

Hi watzmann.

In our case we're developing our own software for the CNC milling machine and we came up with something that is able to draw curves.

We realized curves in terms of x and y movements with rate of change.

We're modelling a curve as being made up of many many small straight lines. Prompt the user for start,end coordinates of curves and its radius.Divide the curve into many many small straight lines.For each line find gradient.The gradient will determine the movement of the x and y motors.In general,the gradient is the speed of the y motor relative to the
x motor.Put all of this in an array and execute...we're still in testing phase
but its good enough for us...wanted to compare the quality of the curves with some other method so that why i asked you...is that CNC software you're using freeware.?..Can i find it on the net?

Thanks
Bondfire

 

[watzmann]

ya i think you need to try differant software to get the suitable resoulation for your machine . ,

i think it will be difficult to find a totally free software , it's just shareware for 1 month .

you have to search underthis category .
good luck

what are you going to use in your machine ..... Drive belts or Screws??

 

[Bondfire]

Hi,

we used gears and belts previously but they kept coming off...now we're using screw threads

 

[williB]

hi bondfire,
if you are using lead screws to drive your machine , be aware that the regular type have a certain amount of slop in them which grows with use..
slop is when you are turning it one way and change the direction , they make ball bearing ones that take the slop out automatically, but of course are much more expensive..

 

[jbeng]

... if you are using lead screws to drive your machine , be aware that the regular type have a certain amount of slop in them which grows with use. Slop is when you are turning it one way and change the direction ...

A phenomenon commonly known as "backlash"

... they make ball bearing ones that take the slop out automatically, but of course are much more expensive..

Devices commonly known as "ballscrews"
JB