3D V12 Engine


Introduction: 3D V12 Engine

Hey everyone,

In this instructable I will try to get you more familiar with123design. I guess there are a lot of sentences like "and then", "next" and so on and i already apologize for that :) The instructable seems probably not the easiest to start with when your new to the program but I tried to describe the steps with as much information as possible. But I just did this at the beginning because I assume you are learning aswell during the process of creating your 3d model.

So what am I gonna show you?

I tried to design a model of a V12 Engine. Now many people may say that you cant do that with this software and they are right. I juast wanted a model of the engine so that people can have a look whats inside of the big metal block called engine. And because of that I will not close the engine completely (the top will be missing so that you can see the piston-heads and the bottom will be missing so that you can see thhe crank). I will definitley notput in stuff like oil and gas pipes or something like that. because the bottom is missing I will put it on some kind of stand where it kan rest.

What I want you to do ?

I want you to read through the Instructable and maybe learn something about 123Design. And I would really appretiate it if you could tell me when there are faster/better/more accurate ways to do something. And the biggest thing is I want you to vote for me in the 123design contest, because I really want that 3d-printer. If you do so I'll already thank you.

I hope you will enjoy this Instructable.

Step 1: Connecting Rod

The first thing we want to do is the "Rod" that connects the piston with the crank.

Step 1:
Make a Rectangle (You can find it in the Menu under primitives) with the lenth 155mm (the width doesnt matter in this case).
On the top end of it add a circle (also found under primitives) with the Diameter of 22mm (123Design always uses the radius so type in 11mm) and on the bottom a circle with the Diameter 38mm (r:19). Make sure they line up!

Step 2:
Use the Polyline tool wich is found under Sketch and set the start point of it on the half of the circle. make the first line so that it is cutting the circle in 2 same pieces. Make the next line to the lower/upper circle depending where you started and do the same thing again. withe the last line your closing the sketch and it should look like the one in the picture. You can now delete the Rectangle we drew before.

Step 3:
Use the Polyline tool again to draw the shape from the picture.

Step 4:
Add a circle with the Diameter 35mm (r:17.5) on the top circle (make sure they line up exactly). And a 70mm Diameter (r:35) circle on the bottom one. Then line up the "U" shape we drew in step 3 like it is shown in the picture

Step 5:
Make a circle with the diameter 160mm (r:80) and place it so that the circle touches the 2 points i highlighted in the picture.

Step 6:
Use the two arc point tool (found under Sketch) and set the center of the arc at the same spot the center of the 160mm circle then set the arc where I marked them before. Then use the polyline tool again and make a shape like on the picture.

Step 7:
Redo step 6 with the top circle (This time use a 80mm diameter circle).

Step 8:
Select the green highlighted shapes and use the command Extrude (Menu:Construct), type in 11mm and select new solid. Select the red highlighted shapes and do the same. Make sure they are set to New Solid too.

Step 9:
Hide the green solid, select the first red shape and click on the pattern menu. Select Mirror and click on Mirror Plane. Select the green highlighted side of the solid and hit Enter. Do the same with the other solid.

Step 10:
Select the 2 smaller circles and the U shape and select Extrude. This time type in 11mm or more. Make sure its on cut.

Step 11:
Use the combine menu and select the 3 solids. Hit enter. Done.

Step 12:
Use the Two-Point_arc tool again and draw a half circle with the diameter of 38 mm (180°, r:19). Draw two other arcs with the same ceter point (they dont have to be 180°, they are just for easier drawing).

Step 13:
Use the Polyline tool and use one of the ends of the 38 mm half circle as start point then make a line that is 11mm long. make another one with a 90° angle until it hits the 70 mm circle. Make a third line until you hit the middle circle. Delete the middle and outer circle.

Step 14:
Use the Two-Arc tool again and set the center the same place the half circle is. then connect the 2 ends with a circle. Extrude it for 11 mm.

Step 15:
Make 2 5mm circles and place them in the middle of the extruded solid like I did in the picture. It should automaticlly lock in the middle. Extrude it by using cut. Do this with the connection rod aswell (I forgot to do that (: )

Step 2: Crank

Step 1:
Create a 130mm (r:65) diameter circle. Extrude it to 7.5mm. Select the upper Edge and click on the Chamfer Button. Chamfer the Edge for 3.25 mm.

Step 2:
Add a circle with the diameter 60mm (r:30). Extrude it with 27.5mm and select join.

Step 3:
Create a Rectangle with the length of 40mm (the width doesnt matter). Place it on the center of the circles and on top of it add a circle with the diameter of 38mm (r:19). Extrude it 20mm, but this time the other way so type in -20.

Step 4:
Use the Polyline tool and draw a triangle. Type in 17.5° and 150mm do the same on the other side and then connect them. Add a 50mm (r:25) circle like i did in my sketch. Then make a line through the circle that it looks like a pyramid with a round top. Use the polyline tool and redraw the bottom of the pyramid. Add a square around it with the measurements 150x200mm.

Step 5:
Extrude it 10mm. Extrude the pyramid and make shure you cut it. Make a square at the bottom and Extrude it (Use cut).

Step 6:
Place the solid with the pyramid cut out of it over the disc we made at the beginning. Make shure the top is right at the edge of the disc. Extrude the pyramid-cut-out and delete it afterwards.

Step 7:
Select the cut out disc and click on the mirror tool. Then select the 38mm circle and hit enter

Step 8:
Copy the whole solid and paste it again (copy: ctrl+c, paste:ctrl+v) and move it 95mm (Then it should line up). Repeat it until you have 6 of them.

Step 9:
Rotate each of the solids like I did in the picture.

Step 10:
Use the Polyline tool again and redraw the two shapes from the picture.

Step 11:
Use the Revolve tool found under the Construct menu and select the first shape. Select Axis and type in 360°. Redo this process with the other sketch. Use the first solid and place it on one end of the crank and put the other one on the other side.

Step 3: Piston

Step 1:
Redraw the sketch with the Polyline tool!

Step 2:
Use the revolve tool found under the construct menu and click on the sketch. Make shure you click on axis not on profile and select the axis i marked green. Then type in 360° and hit enter.

Step 3:
Hide the solid and make a 25mm high rectangle (this is just for easier handling). Add another rectangle with the measurements 14x24 mm and place it like I did. Remove the first ractangle. Select the remaining rectangle copy it and paste it.Then move it 90 mm to the left.

Step 4:
Unhide the solid again and move the 2 rectangles up by about 60 mm. After that select them again and extrude them (with the cut option) to about 100 mm.

Step 5:
add a circle (diameter: 22mm, r:11) on the side of yourr piston. It should lock in in the middle of it. Then extrude it with the cut option to about 80. THen select it again and extrude it again but select new solid and extrude it to 76 mm. Now you have the piston and the bolt for it.

Step 4: Crankcover

Step 1:
Redraw the picture (I think you are now able to do it ). You can delete the square at the end.

Step 2:
Extrude the big circle for  130mm. Extrude the inner circle and use the cut option. Then extrude the 4 small circles (join). Select the lines where the small tubes cut the big one and select them. Click on fillet and type in 15 for each of those lines.

Step 3:
Fillet the lines on the inside aswell with 15.

Step 4:
Add a circle with the diameter 12 (r:6)  on each of the small tubes and extrude them with the cut option.

Step 5:
Add 2 inner circles one with the diameter of 90 (r:45) and one with the diameter of 100mm (r:50). Extrude the bigger one for 130mm and Extrude the inner one aswell with the cut option.

Step 6:
Copy the whole solid (actually 2) and paste it 6 times next to each other (95mm distance).

Step 7:
Copy the 90mm circle 6 times too and extrude it (cut). Click on the combine menu and select all the solids that are on the screen.

Sadly the program randomly crashedand I lost all the data. So that this doesn't happen to you save your procect every once in a while. Because I didnt want to do all those steps again I will use a solid i made before to use for the last steps.

Step 8:
Make the shape from the picture and rotate it 90°.

Step 9:
Extrude the sketch for 40 mm and move the sketch 110 mm then extrude it again for 20 mm. Do it until it looks like on my picture. (The green measurements are for extruding. The Red measurements are the distances between the solids.)

Step 10:
Add the sketches to the first solid and extrude the 3 rectangles for 625 mm (join) and the circle for 625mm aswell (but cut!). Use the cylinders where the pistons are placed in and rotate them for 45° and place them on one side of the new solid. Then copy it, rotate it for 90° the other way and place it on the other side.

The last 2 steps are just the stand for the model. I think this is easy to copy (I extruded it for 40mm)

Step 5: Assembling

It is quite hard to assemble such a complex model in 123design so I decided that i dont really have to, because I want it to be 3d printed and for that  I would need to print out each part on its own. I did not put in the connection rods in this "preview" because it just didnt work out. I hope that I am able to print all these parts out someday (maybe shrink the size of the whole model a bit :)  ).

But for easier project just select insert and and move it to where you want it.

If you have any questions feel free to ask

and pls Vote for me in the 123Design Contest!



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    Epic model! I like the way you decided to present the information. Hope this project places well!

    Cool! Is this the entire engine or are you also planning on adding other things to it (like little valves or a carburetor or exhausts)?

    2 replies

    I might add something like this but then I would use a more complex CAD software. I wanted it to be a model that is open so that people can see how the pistons and the crank works.

    Okay cool. Another thing that would be awesome and complete-looking would be to 3D print a see-through/translucent engine block (but I don't think it is possible to 3D print like that yet). Perhaps 3D printing parts then making molds to fill with translucent plastic could work.

    A further but altogether more complex step would be to add a small electric motor to it to turn the crank and in turn, move the pistons.

    I own a auto repair shop and would love to have something like that in my office.

    thats really impressive! PM me and I will print it for you


    Very impressive for a guy like me that is just learning. New concept i have learned from using 123D is of adding a shape to subtract from a different shape.
    Nice work.