wao guys thanks a lot for your help!!!!!

I probably will first buy a kit and get to know the 3d printing world and afterwards maybe build my own 3d printer.

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I probably will first buy a kit and get to know the 3d printing world and afterwards maybe build my own 3d printer.

It may make more sense to just buy a printer or a kit.  to start with and learn how to use it and maintain it. Then build one as a second machine.

I considered building one but decided against it for my first printer.

to build one from scratch you will need:
A design for the printer. They are out there many are open source.
a complete shopping list of parts
Then you need to source all the parts.
then assemble.
then set your firmware settings for your machine then adjust and tune.

But  KSAs
Knowledge of need parts
ability to effectively purchase the needed items.
KSA to assemble the mechanical parts
Wire all components together load and program the firmware.
and tune everything.

You will need a good working knowledge of mechanics and electronics as well as Some programming skills to pull it off.
Tin

The basic hardware operations general occur like this: The plate is first prepped for having extruded plastic applied (glue, kapton tape, whatever). Filament is loaded onto a reel holder and fed into the extruder. If there is a heated bed, it must preheat before the print (some programs require you do this manually first). The extruder is preheated. Then the axis are generally usually homed (sent to 0 position on each axis. the extruder will move to x0, y0 and the z axis will return to z0 as well). The controlled will then begin executing the gcode... the extruder will move to the first instructed 3d coordinate (usually right above the plate a paper or two widths above) and the extruder will start pumping out hot plastic as the extruder rides the first 2d layer toolpath. as each 2d layer is completed, the z axis advances one increment and the next layer is printed... so on and so on til a complete 3d object is done. Then the plate cools, the extruder cools, and once cooled you can remove your print.

So the very basics of what you need are A) the Hot end and Extruder, B) rails or rods or sliders of some sort for each axis C) either threaded rod or belts to drive each axis, D) at least 1 stepper motor per axis plus at least one stepper per extruder (on a single extruder printer that's a minimum of 4 stepper motors), E) End stops (limit switches), one on each side of each axis (minimum 6), F) One motor controller per stepper (minimum 4) G) one microcontroller board with plenty of pinouts, H) A frame (there are alot of different types of frames) I) A;; the interim wiring, J) some sort of build plate, K) a computer to flash firmware to the board, build and slice 3d models, and to operate the software to export the instructions to the printer. These are the bare minimum parts on the average 3d printer, and is not by any means a complete list.

This says nothing for all the fittings, screws, nuts, bolts, glue, measuring, programming, calibrating, and such that will need to go into it. Most of the mechanics and framing can be made on the cheap with household hardware parts, but the stepper motors, motor drivers, and controller board are things you will probably need to buy new. If you were really resourceful, you might find steppers inside old printers or cd drives, if you happen to live by an e-waste dump. Most modern printers use regular DC motors with encoders (believe me... I tried finding steppers in old printers from the thrift store). You can also extract the rods from the printers to build a rail system, but you will need to buy bearings. Some 3d printers have been built with encoder motors, but I think it'd be easier to use steppers. The basic idea is to build a rail system for each axis.. it's often easiest to place the build plate on the z axis on it's own rail, the extruder is usually attached to the x rail axis on which it slides left and right, and that entire rail is mounted on two rails (one on each side) to allow it to slide forward and backward. Belts or threaded rod, driven by steppers, advance each sliding apparatus in a precise number of increments according to instructions sent to the microcontroller board in gcode, where it is inerpreted by firmware.

Of coarse there are several different frames and mechanical schemes... you should look up the advantages and disadvantages to each. Supposedly the easiest one to build is described above, but you can also build a gantry style (looks like a cnc mill) or a delta bot (Look it up... it's pretty funky). I even saw an extruder on a wheeled bot that extruded onto the floor, but this is a very 2 dimensional scheme. They also have 3d pens... the logistics are more complicated, but you can achieve 3d prints with a steady hand and quick wit. And if you are getting super fancy, there are liquid resin 3d printers which use lasers to cure resin in layers to build up a model/object.

The basic flow of information goes like this: You create a model in a 3d program (like tinkercad). Then you save it as a 3d file (such as an STL). You use a slicer program to turn it into gcode (some slicer programs are integrated into the printer software) which contains instructions on bed temp (if you have a heated bed), tool paths, extrusion rates, etc. If you are using a seperate program to slice, you must save the gcode file, then open it in the printer software. Then the printer software can send instructions to the microcontroller, whose firmware executes the instructions.

These are some broad general basics to a 3d printer. You should find some walk throughs of builds to see what the actual build process is like, and to see if maybe you might want to take the easy way out and just buy one. They are pretty cheap, and I have had incredible results from a jailbroken Davinci (easier to hack an already built one than to build one yourself. Just sayin) If you do decide to build one, be prepared for alot of sleepless nights and tedious work. And have lots of measuring devices, tools, and aspiring handy.

Adafruit, Jameco, Microcenter, Amazon, and Ebay have lots of various electrical components and some hardware components you will need. If you go the cheap route, the local hardware store has rails, bearings, and framing material. You may need to customize your build to go this route, or follow someone else's build.

3ders.org, instructables, hackaday.com, and many more have various levels of detailed build plans ranging from broad and general, to specific complete with bill of parts and detailed instructions and measurements. Hell, just google "how to make a 3d printer" and you will probably get a ton of good resources.

As always, a little bit of creativity goes a long way

I am new to 3d printing and would love to build my own 3d printer. But the problem is I don't know how or where to get started? Could you help me please????

thanks a lot for your help