Introduction: DIY-SLS-3D-Printer

Picture of DIY-SLS-3D-Printer

In this Instruction, I want to show you how to build a DIY Selektive-Laser-Sintering (SLS) 3D-Printer. I am 17 years old and made everything by myself. Since 6 month my big dream was to build up a working SLS-3D-Printer, but there is a problem. The most SLS-3D-Printers are very expensive and only aviable for the industry. So I build my own printer. Often I was disappointed. Especially with the material, but after a month of experiments I found the right powder for a test print.

Here are some specs:

  • 1W 445nm Laserdiode
  • 8x8x8cm Buildvolume
  • 36x54x60cm Outsidedimensions
  • CORE-XY Movement
  • Speed: 60mm/s tested, 300mm/s possible
  • costs around 400€

If you like my Instructable, please vote for me in the 3D Printing Contest :-)

Step 1: Video / Test Prints

Picture of Video / Test Prints

This is my first test print with this printer.

The gear is printed in black powder coating material at 60mm/s.

It has a size of 3x3x0,5cm and took one hour to print.

Video of the gear:

Step 2: CAD-File

(If you can't see the interactive 3D model above, its probably because you're not using a WebGL-enabled browser, or you're using the Instructables Mobile app)

Here you can download the complete CAD-file. .f3d is for Fusion360, .step for other CAD-programms :

Step 3: Mechanical-Parts

Picture of Mechanical-Parts

20x20mm Aluminium-Extrusions:

  • 4x 600mm
  • 12x 500mm
  • 8x 320mm
  • 1x 300mm

smooth rods:

  • 2x 8x500mm
  • 2x 8x285mm
  • 2x 8x450mm
  • 4x 8x255mm

threaded rods:

  • 2x M5x140mm



Aluminium plates:

I found my plates at the local scrap yard, so I don't have a link for you.


  • 8x M4x40mm
  • 2x M3x30mm
  • 24x M3x8mm
  • 8x M3x18mm
  • 4x M2x6mm (Endstops)
  • 200x M5x10mm DIN912
  • 100x M5x10mm ISO7380

Step 4: Electric-Parts

Picture of Electric-Parts

Here are all required electronic parts for the SLS-3D-Printer:

Step 5: Printed-Parts

Picture of Printed-Parts

Here is the part list of all required printed parts :

2x powder box.stl
2x Z-Table.stl
2x Z-Motor.stl
2x Z-Axis Top.stl
2x Piston.stl
2x Pusher-Motor.stl
2x Pusher-Idler.stl
2x Pusher.stl
4x 8mm-Rod-holder.stl
2x Motor.stl
1x Idler-Endstop.stl
1x Idler.stl
2x Y-Carriage.stl
1x X-Carriage.stl
1x X-Carriage Top.stl
2x Idler Clamp.stl
2x Belt tensioner.stl

Last change: 10.06.2016

I printed all parts with:

  • 25% Infill
  • 0.2mm layer
  • black PLA

Step 6: Build the First Stage

Picture of Build the First Stage

What you need:

  • 2x 500mm Extrusions
  • 2x 320mm Extrusions
  • 4x M5-Corner Bracket
  • 14x M5x10mm DIN912 Screws
  • 14x M5 Extrusion Nut
  • 8x M5x10mm ISO7380

At first you attach the two Z-Motor printed parts to your base frame. Then you add four M5-Corner brackets to the frame

Step 7: Build the Pistons

Picture of Build the Pistons

What you need:

  • 4x small wood plates
  • 3x big wood plates
  • 12x wood dowels

I build my pistons out of screen printing plywood, because it is very easy to work with wood. Also it is very cheap :-). An other plus point is that the surface is very smoot, which is better for the piston.

I use some wooden dowels to connect the woodplates to eachother.

I recommend to download my Fusion360 that you can cut the plates very accurate.

Also please look at my additional PDF:

Step 8: Connect the Wooden Box to the First Stage

Picture of Connect the Wooden Box to the First Stage

What you need:

  • 4x M5x25mm DIN912 Screws
  • 4x M5 hex nut
  • 4x M5 washer

Now you can screw the wooden box to the first stage. Use some washers for the M5x25mm screws.

Step 9: Build the Second Stage

Picture of Build the Second Stage

What you need:

  • 2x powder box printed part
  • 2x Z-Axis Top printed part
  • 4x Cornerbracket M5 Nut
  • 22x M5x10mm DIN912 Screws
  • 22x Extrusion Nut
  • 2x 500mm Extrusion
  • 2x320mm Extrusion

The main frame of the extrusion is very similar to the frame of the first stage. The only difference between them are the printed parts. For the second stage you need the powder box and the Z-Axis top parts. Connect the parts like in the pictures

Step 10: Pusher

Picture of Pusher

What you need:

  • 1x 300mm Aluminium Extrusion 2020
  • 2x Pusher printed part
  • 4x LM8UU
  • 6x M5x10mm DIN912 screws
  • 6x M5 extrusion nut

At first you have to push the 300m Extrusion inside the printed part. Then you connect the extrusion with six M5 extrusion nuts. Before pressing the LM8UU inside the printed part, please predrill the printed part with a 15mm drill.

Step 11: Connect the Second Stage to the Wooden Box/ Install the Pusher Motors

Picture of Connect the Second Stage to the Wooden Box/ Install the Pusher Motors

What you need:

  • 2x Nema 17 Motor
  • 2x Pusher Motor printed part
  • 2x Pusher Idler printed part
  • 8x M3x8mm screws
  • 12x M5x10mm DIN912 screw
  • 2x 608zz Bearing

At first you have to connect the second stage to the wooden box like the firts stage. You simply use four M5x25mm screws. Then you can attach the pusher motor printed part to the second stage. You screw the printed part to the extrusion by using three M5x10mm DIN912 screws. For the Nema 17 motr you use four m3x8mm screws. Once you screwed the motor to the printed part, you attach a 20th GT2 Pulley to the motorshaft. At the other end of the second stage, you attach the pusher Idlers printed parts. Then you push an 608zz Bearing inside the printed parts. This is necessary for the 8mm smooth rod, which will be insert later.

Step 12: Install Z-Axis

Picture of Install Z-Axis

What you need:

  • 2x Nema 17 Motor
  • 2x Z-table printed part
  • 8x M3x8mm screws
  • 8x LM8UU
  • 2x 8x255mm smoothrod

At first you need to press the LM8UU Bearings inside the Z-Table printed part. Then you simply insert the Z-Table with the LM8UU into the 8mm smooth rods.

Step 13: Pusher

Picture of Pusher

What you need:

  • 2x 8x500mm smoothrods
  • 4x 8mm Rod-holder printed part
  • 8x M5x10mm DIN912 Screws
  • 8x M5 Extrusion Nuts

Now you finished the pusher and the pistion unit for the SLS-3D-Printer. So now you can attach them together. You simply need to push the smooth rods trough the pusher bearings. Then you can screw the smooth rods to the second stage.

Step 14: Y-Carriage

Picture of Y-Carriage

What you need:

  • 2x Y-Carriage
  • 4x M4x40mm DIN912 Screws
  • 8x F624zz Bearing
  • 8x M4 self locking hex nut
  • 4x M4 washer
  • 4x LM8UU

This is the first step for the X/Y linear Laser movement. The X/Y Movement of this printer based on CORE-XY. If you don't know what COREXY is, please visit the this website COREXY. The Belt is appropriate on different levels, so the belts don't rub to eachother. The big advantage of COREXY is, that the weight of the moving mass is lower than conventionell cartesian movement systems. This means that you can drive extremly fast, because you don't need so much force to accelerate the mass. I've tested 400mm/s on my printer :-)

To build up the Y-Carriage, please take a look at the pictures. Don't forget to screw the F624zz bearing on different levels. Later this will be very important.

Step 15: Idler

Picture of Idler

What you need:

  • 2x Idler Clamp printed part
  • 1x Idler printed part
  • 1x Idler with endstop printed part
  • 8x F624zz Bearing
  • 4x M4x40mm DIN912 Screw
  • 8x M4 self locking hex nut
  • 4x M4 washer

Like in the step before. Don't forget to screw the F624zz bearings on different stages that the belt don't rub to eachother.

Step 16: X/Y Motor

Picture of X/Y Motor

What you need:

  • 2x Nema 17 Motor
  • 1x X-Motor printed part
  • 1x Y-Motor printed part
  • 8x M3x8mm Screws
  • 2x GT2 20th pulley

You need to repeat this step two times. The only difference is, that you use for one the X-Motor-printed part und the other one Y-Motor printed part. Also you have to turn the GT2 pulley of one motor in 180°.

Step 17: Attach the Third Stage

Picture of Attach the Third Stage

What you need:

  • 2x 8x450mm smoothrods
  • 2x 8x285mm smoothrods
  • 4x LM8UU
  • 12x M5x10mm DIN912 Screws
  • 12x M5 Extrusion Nuts

Now you can combine the Y-Carriage, Idler and Motor with the third stage. You push the the smoothrods inside the defined holes. Now you need to screw the X/Y Axis to the third stage. Use the twelve M5x10mm screws to connect the Motr and Idler printed part to the extrusions. Don't forget to insert four LM8UU for the X-Carriage.

Step 18: Attach the X-Carriage / Last Stage

Picture of Attach the X-Carriage / Last Stage

What you need:

  • 1x X-Carriage printed part
  • 4x belt tensioner printed part
  • 4x small metal pin
  • 8x M3 hex nut
  • 2x 2m GT2 Belt
  • 8x M3x18mm screws
  • 2x 500m Extrusion
  • 2x320mm Extrusion

At first you have to install the last stage of extrusions. You simply have to install it like the other extrusions before. After that you can attach the X-carriage to the LM8UU Bearings. You simply have to push them inside the printed part. Then you fix the X-Carriage with four zip-ties. For the Belt you have to put an small metal pin inside the Belt-tensioner. Then you can tighten the belts with the M3x18mm screws. Make sure that your belts have the same lenght!

Step 19: Build the Piston

Picture of Build the Piston

What you need:

  • 8x M5x25mm screws
  • 8x M5 Hex Nut
  • 4x Aluminiumplates (12x14cm)
  • 8x M3 hex nut
  • 2x packing material (From your mechanical parts or etc.)

This step is one of the most important ones, because the pistons are the heart of the printer. I made a lot of experiments, how to make a good piston. So this is my solution :-)

I am using an aluminium || packing material || aluminium sandwich as a piston. You have to cut the packing material so that it will press itself to the wooden box. The result is that no powder will fall through the piston. You can level the pistons by pressing the aluminium plates together.

Step 20: Install Small Extrusions to the Pusher

Picture of Install Small Extrusions to the Pusher

To garanteer that all the powder will push inside the next piston, I attached some small 10x10mm Extrusions. Make sure, that the pusher can move freely. The space between pusher and extrusions should be <1mm.

Step 21: Install the Laser

Picture of Install the Laser

What you need:

  • 1x Lasermodule
  • 4x M3x10mm DIN912 screws

Now can can screw the lasermodule to the X-Carriage. You do that by using four M3x10mm screws. Once you installed the laser, make sure that you are not static charged and touch the lasermodule. The laserdiode is a very sensitive element and can break easily.

Step 22: Outsite Plates

Picture of Outsite Plates

Now you can attach the Aluminium plates for the housing by using some M4x6mm screws. I'am using 1.5mm Aluminium plates for the housing. It is highly recommend to download the Fusion file from the the Top, so you can cut your plates in the exactly dimensions.

Step 23: Powersupply

Picture of Powersupply

You can use nearly every ATX-PSU which has a 12v Output. The printer needs all in all less than 100w of power, so you don't need a strong powersupply, but If you want to change later to an heated piston I recommend not to buy a ATX-PSU. Search on Ebay for server powersupplies. Mostly they are cheaper and have a lot of amps on the 12V Line.

Step 24: Arduino / Ramps 1.4

Picture of Arduino / Ramps 1.4

The Ramps 1.4 is one of the most used electronic boards in the reprap community. It is very cheap and it can be used for many projects. I marked on the picture, where you have to plug your wires that it will work.

Step 25: Laserdriver

Picture of Laserdriver

If you build your own Laserdriver, I recommend a LM317 constant current circuit. It is cheap and can provide max. 1A for the Laserdiode. You can calculate the current for the laserdiode with this formula: [ I = 1,25 / R1 ]. I'am using an 1,5 Ohm power resistor, so I provide max 0,83 mA for the laserdiode.

I attached a circuit drawing with all the requierd electronic parts (see pictures)

Step 26: Repetierhost

Picture of Repetierhost

In my opinion Repetier-Host from Repetier the best all in one Software for FDM-3D-Printer. With some modifications you can also use it for my DIY-SLS-3D-Printer.

You don't have to modify Repetier-Host, beacuse it is just a host software, you have to modify the arduino code and the gCode-generator, that it will work.

Step 27: Arduino-Firmware

Picture of Arduino-Firmware

To controll the SLS-3D-Printer, I'am using a modifed Repetier-Firmware from Repetier.

This firmware has an feature, that overrides the E-Steps of your Slicer to an Laser, called "Laser-Mode". That means that I can use normal FDM-Slicers like Slic3r for generating the Gcode for my printer.

You can upload the config.h to the Repetier configuration tool . Then download the complete firmware, open it in your Arduino IDE and upload it to your Arduino mega 2560.

Once uploaded, go to Repetierhost-->Config-->Firmware EEprom Configuration.

Then you upload my default Eeprom file, which includes all the parameters like steps per mm, acceleration, feedrate...

You can download my default configurations here:

Step 28: Modify Slic3r

Picture of Modify Slic3r

I'am using Slic3r to generate the Gcode, because it has some features like custom Gcode on layer change, which is very important for my DIY SLS 3D-Printer, because I need an custom Gcode for the powder pusher.

Slicer is allready included in Repetierhost, so you don't need to download slic3r as a standalone programm.

You need to open the Slic3r configuration. See pictures, where you have to click

Then you go to -->Printer Settings--> Custom G-code:

Here you type in:

Start G-code

G28 // home all axis

M3 S50 // acctivates the Laser with a power of 50 from 255

End G-Code:

G28 X0 Y0 // home X- and Y-axis

M84 // disable motors

G204 P0 S0 // disable extra Motor for the powder pusher

After Layer change G-code:

G202 P0 X0 // move extra Motor for the powder pusher to 0mm

G201 P0 X300 // move extra Motor for the powder pusher to 300mm

G201 P0 X0 // move extra Motor for the powder pusher to 0mm

( //... = comments, to understand the custom Gcode)

For the other configurations, please download my slicer config file:

Step 29: Make Your Print Material

Picture of Make Your Print Material

Normaly SLS-3D-Printers printing with Nylon Powder like PA12 which is very expensive. It costs around 200€/kg. This is too expensive for me. If I would fill my buildvolume of 8x8x8cm with PA12. The Material would costs more than my complete printer. So I searched for untypical Materials, which can be sintered, like powder sugar. I mix the powder sugar with some carbon powder, but I had no success. The sugar clumps into small drops (see pictures) und doesn't create an flat surface.

So I've been searching for an other material. Accidentally I found black powder for powder coating on Ebay. It has better characteristics than I expected. I can print the material without a heated bed and with just 200mW laser power at 60mm/s. This is great, but not perfect. The disadvantage of this material is, that it is not very rigid. It breaks easily. But for test prints it is ok.

I think it will work with a material like nylon or an other thermoplast when I add a heated bed, because everything else works nearly perfect (electronics, mechanics, laser...)

If there is someone out there, who has some Ideas about a new material which is inexpensive and can be sintered, please let me know. You would help me a lot.

Step 30: Safety First!!!

Picture of Safety First!!!

Lasers are very dangerous and can make you blind. Don't work without safety glasses!


CédricB26 (author)2017-10-31

Thank you for this great tutorial. Once we complete this tutorial, will be easy to do a new 3D printer with a larger build volume (I am thinking of 40x30x30 cm)?

skowerr (author)2017-10-14

Have you concidered using finely ground PLA powder?

You could use a failed pla print grind it on a belt sander and sieve out the larger crumbs. That would be a nice and cheap source of the material.

mike.t.dixon (author)2017-10-06

This is probably something most people don't want to do. but... if you spend a little time you can pretty easily mill your own powders... i built a large tumbler, using a 5 gallon bucket with a water tight lid (has an O-ring), some 2x4, a few bits of 8mm rod, couple bearings, and a large AC motor off eBay. you can whip your self up a 5 gallon ball mill... using some cheep steel ball bearings of your choice from eBay, (i use 1/4) and some abs, pla, nylon (or what ever you chose) pellets which are cheap and easy to get (again eBay) toss a couple pounds in there with your bearings and let it run until you get the size you want.

tommax12138 (author)2017-09-28

could you contains a detailed account about laser and code?

BrandonMski (author)2017-08-29

Man this is just downright impressive! I've been considering taking on a similar build but can't justify the expense until I can reasonably source the metal powder and a laser adequate enough.

MrCheatak (author)2017-06-05

Is your SLS capable of working with metals?

How powerful laser should be for that?

SharS3 (author)MrCheatak2017-06-28

Yes, if you find any information regarding this, please share !

mikew385 (author)SharS32017-07-16

You will need to preheat your powder supply to achieve Metal melting temps with the Laser in this instructable. It's ideal to do so for non-metal powders as well. One company that is developing 3d metal production currently uses Halogen lighting with a heated bed to achieve melting point (I'm not at liberty to say which company).

MrCheatak (author)mikew3852017-07-17

Hm, I guess pre-heating is a technology, but with this DIY printer its not a good idea =/

johnsamisoni (author)2017-07-04

Does anyone know where to buy nylon 12 powder?

mikew385 (author)johnsamisoni2017-07-16

Not cheap, but Aliexpress is probably the best value where you can find it for $50/kg if you purchase a large enough volume. Stateside from an authorized Evonik supplier, you're looking at anywhere from $150 - $350/kg

VagelisA (author)2017-06-19

Hey! Amazing build! well done!!

Well I did a quick search in Alixpress you can find cheap Nylon powder!

Take a look at these links:

Keep us updated if you do new tests.

hjarrettusf (author)2017-05-16

I know you explained it, but I'm struggling to follow how the G-Code goes into the Arduino code. From what I can understand, you have a base Stepper Motor Setting. Then you take the G-Code and insert it into the Arduino code? Or does that somehow just talk to the Arduino and tell it what to do? (I'm good at the making part, not so great at circuits or programming). Thank you!

chubby8 (author)2016-10-27

have you tested this out with other plastic powders? I'm about to design and build a small SLM printer and a temp to use polymorph powder, (£14 per 500g tub) with black powder dye mixed in. I would love to see what other parts you have printed on this machine. thanks

Vulcaman (author)chubby82016-10-27

Sadly I don't printed any other powder than the powder coating powder succesfully. This has something to do, that I don't have an heated bed/ heated chamber /heated partbed. Even for sugur you need to heat the powder.

But all these problems where solved in the next version. So stay tuned.

Do you want to build a SLM Metal printer? Which Laser do you have?

NeilRG (author)2016-10-27

excellent disciplined approach to engineering and design. I wish you the best in your carreer.

lde rivera (author)2016-08-26

epic project mate, i was wondering if it would work with aluminum powder?

Vulcaman (author)lde rivera2016-08-27

In this setup it will not work with aluminium powder. If you plan to sinter metal, you need an very strong laser >100w and the right wavelenght. Also you need to print in a gas atmosphere to prevent self explosion of the powder. You have to take attention on static and many other security features. It is not that simple as expected :-)

marshalcraft. (author)Vulcaman2016-10-13

What about fine aluminum powder mixed with say 20% fine wax powder. Then sinter part in oven, wax melts away leaving aluminum part with slight reduction in size.

Also i think with metal sls as you describe the inert gas is to prevent oxidation.

tobias.sobkowiak (author)2016-08-07

Very nice work.

Thelaser housing won´t be shipped to germany and where do you get the brackets from. Is it also a stl file?


i forget to upload the brackets. Sry. I attached them in my comment.

You can use any housing for an TO-18 Laser. If my liked one is not aviable, I would chose this one:

THX. And where did you get you slotnuts from? Could you publish an Illustrator file or something like that about the wooden box...No clue how to built it. Can´t with Fusion.

For the slot nuts, please look at my Vulcanus V1 instructable. I made the nuts out of normal hex-nuts. I added an additional File for the pistons

KarthickK13 (author)2016-08-14

very nice and helpful.

will it work with metal powder?

KarthickK13 (author)2016-08-14

very nice and helpful.

will it work with metal powder?

CFL_Browncoat (author)2016-07-31

This is easily one of the best-documented projects on here. Excellent work.

mbonifax (author)2016-07-06

Great job. Clear instructions. Giod. Thanks

undinstructable (author)2016-07-04

Congratulations on this great project!
Thanks for sharing!

shadowtec (author)2016-07-04

This is one of the best instructables I have seen.

next step is a metal version :P

Well done mate!

Raitis (author)2016-07-02

This is amazing and I can see you have a great mix of technical knowledge and problem solving skills. Way to go, keep it up!

chriskelly (author)2016-06-30

Is it v-slot where can I buy this?

william.hynes (author)2016-06-16

can this create non-prismic bodies, i.e. not simple vertical extrusions?

chubby8 (author)william.hynes2016-06-26

yes. This kind of 3d printer is the least restrictive when it comes to possible part geometry. It is the perfect machine for printing organic, complex, even hollow shapes. It's even posible to integrate internal mesh or honeycomb structures in to your parts.

MechEngineerMike (author)2016-06-24

17 years old huh? That would not have been my guess because this is excellent work! Keep it up

squalyl (author)2016-06-14

Good project! Impressive! But be DOUBLE CAREFUL with lasers.

To protect your eyes from BLUE laser you need RED googles that block blue and green light (opposite of the spectrum, as far as possible).

Green googles are not good enough, because green color is too close from blue, green googles do not block enough blue light. Or you need excellent green googles.


Same idea, when you play with RED lasers you need BLUE googles.

The error (which you did not make) is using BLUE googles for BLUE laser, because blue laser pass through blue googles. Same for RED.

starphire (author)squalyl2016-06-20

I completely agree about being extra careful with eye safety/goggles/shields for something like this.

However, it would be overly simplistic to say that you can judge the blocking ability of laser safety goggles purely by their apparent color. If such goggles are relying solely on the colored dyes added to polycarbonate during manufacture, their ability to attenuate a laser in wavelengths they don't normally "pass" very well, they are not going to reduce the beam by very many magnitudes - a dark tinted pair of grey sunglasses could even in some cases be measurably more effective. Really high quality laser safety glasses are not simple colored gel filters in principle.

ewilhelm (author)2016-06-20

Nice work!

Turkman (author)2016-06-17

19. Step detail place

Turkman (author)2016-06-17

Hi step 11 12 19 detail place

msantospalazzuoli (author)2016-06-17

Very nice work! Congrats!

Barbatruc (author)2016-06-15

Step 7: file "Config.ini"
and Step 26: file "Config.ini"
are not downloadable has we receive back one error saying "wrong username and/or password"...
Can you repost it, maybe in a ZIP?

Vulcaman (author)Barbatruc2016-06-16

Sorry, my mistake. The config.ini in step 7 and 26 was the same as in 28. Yesterday i uploaded the, but I forgot to delete the config.ini

chubby8 (author)2016-06-16

I suggest you build your self a grinding machine, and an array of sieves and meshes... and just try recycling plastic bottles or something.

otherwise try polymorph, it has a very low melting point ~ 60°, mechanical properties similar to nylon, but it is sold as granules, not powder, so it will need to be made in to powder. good luck

wubs (author)2016-06-14

I cannot access the "config.ini" file, can you re-post it, please?

Vulcaman (author)wubs2016-06-15

There was a problem with the ".ini" ending. I zipped the file and uploaded it again. Now it should work :-)

zanboor (author)2016-06-15

It is very nice text an very good explain all thing but in last paragraph (and one of important part) HOW TO WORK ! it is weak.

one of good point is referring to source. and ability of downloading of SLT files.

And again thanks for your effort. and wish great success for you.

zanboor (author)2016-06-15

It is very nice text an very good explain all thing but in last paragraph (and one of important part) HOW TO WORK ! it is weak.

one of good point is referring to source. and ability of downloading of SLT files.

And again thanks for your effort. and wish great success for you.

mr_koz (author)2016-06-14

Nice work dude - you absolutely got my vote!. I have a couple of suggestions:

1 - nylon will fuse more consistently

2 - the commercial units raise the powder to about 5-10 degrees below the materials melting point so the laser only needs to bring the material up a small amount, if you do this you will be able to print faster and more consistent because the material will fuse very quickly - it will cause you problems because you'll need to insulate the chamber and possibly cool the laser unit and other equipment above the print area but it will make better prints.

JayWeeks (author)2016-06-14

I am blown away! When I was 17 I was mostly worried about how I was going to play Portal on my Mac!

This is super cool!

About This Instructable




Bio: I am an 19 years old guy from Germany who love to make things. Later I want to become an Electrical Engineer :-)
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