Introduction: 3D Modeling a Printable Shri Yantra Pendant From an Image (Zbrush)
Hi everyone! This is my 2nd instructable here and I hope it will help you learn how to 3D model things on your own. The journey of learning this stuff has been long and challenging for me and only once I found the right kind of guidance, I was able to finally create the things I had in my head. I do a lot of sculpting with my hands, and this is why I favor Zbrush. It is quiet the tool for those who wish to literally sculpt their 3D models.
This is a tutorial for creating a complex 3D pendant rather quickly by using a black and white image (alpha) to generate the design. This is a pretty cool way to get patterns, drawings, and just about anything turned into a 3D object. I will also touch on some basic sculpting and object manipulation, as well as how to prep your files and export them for print.
You will need a version of Zbrush 4r6 and a wacom tablet+pen to follow along smoothly. I have added pictures and very detailed instructions for creating this awesome pendant, but I recommend you to watch the videos I specifically created to help, as stuff gets a little complicated and it's not easy to find the right menus without the visual guidance. I hope you enjoy this and are able to create amazing things quickly!
I am trying to win the Formlabs1 printer with this tutorial. If you like this and find it helpful, please vote for me in the top right corner of the page! Thanks!!
For the Formlabs1 judges, I just want to say that I have dreamt about this particular printer since it came out and I am grateful for the chance to win this incredible tool, which I dearly hope to use for printing high res prototypes of my jewelry designs and take my jewelry/sculpting hobby to the next level. My big dream is to build a jewelry brand that connects and bands people together by funding a creative craftsmanship skills scholarship program for underprivileged and at-risk youth. I believe that the Formlabs1 printer will become an indispensable tool on my journey towards making this dream a reality. Thank you again!!
Step 1: Find an Image You Like
Anything goes, as long as it is a jpeg/bpm and it's black and white. No color and you don't want greyscale.
Step 2: Using Zbrush to Extrude the Art
Watch my step-by-step video:
1. Begin by selecting Plane 3D from the Tool Palette menu on the right.
2. Draw out the plane with your cursor and press "T" on your keyboard to go into Edit mode (or click on the Edit icon at the top). Zbrush won't allow any sculpting until this is done, as it lives in 2.5D mode before that happens.
3. At the top of your Tool Palette, select "Make Polymesh 3D".
4. Scroll down to Geometry, and click "Divide" 5 times.
5. Open the Alpha menu in the top left corner and click on the tiny circle icon in the corner. Doing this will dock the Alpha menu to your Tool Palette and will make your life easier :)
6. Click Import, then select the art you prepared for this project. Open the file.
7. You will see the icon of your art appear in the Alpha menu. Zbrush reads black as transparent and white as form. Take a look at the icon and make sure the black and white is how you want it. If not, click on the Inverse button at the bottom right corner of the menu.
8. Now you are ready!
9. To turn your image into the seed of your 3D model, you are going to select your Masking brush. The easy way to do this is by pressing CNTRL. You will see in the top left corner, your brush will turn into Masking Pen. Below the Masking Pen icon is the Stroke icon. It should say Freehand. Click there and select DragRect. Then, under that is the icon for masking options. Select your alpha art image. Change the Focal Shift to -100 (top menu slightly to the right) to prevent feathering.
10. Make sure Floor is turned on SHIFT+P, this will help knowing where your middle point is. Begin by pressing down CNTRL + clicking in the center of the plane and drag out the image. Make sure it's very centered - this will affect the sculpting later. Once you're done, open up the Masking palette on the right side menu and select Sharpen Mask.
11. Scroll up to the Subtool menu, and open up the Extract tab (the last one). You can play with the thickness, but 0.02 is good in this case. Make sure Tborders and Double are on. Click on the EXTRACT button. Let your computer process for a min. Once it's done, you will see the edges of your mask pop off a little. Don't move around your art, as the preview will go away. Click Accept (underneath Extract). This creates a new tool in your subtool menu and this is the base of your project. You can select the Plane on the subtool menu and click the Delete button below.
12. Remove the mask, by holding CNTRL+click+drag off your canvass.
- Press "9" to quicksave.
THE FOLLOWING INSTRUCTION IS NOT IN THE VIDEO:
Assuming that you were able to project the mask image of the Shriyantra onto the plane, as centered as possible, it's most likely still not perfect. To fix this, open up the GEOMETRY tab in the tool palette and scroll down to MODIFY TOPOLOGY. Open the tab and click on the button that says Mirror and Weld. Before you click, make sure the X axis is highlighted, and the Z and Y are shaded. This will fix having problems down the line when we use symmetry function with our brush strokes.
Next, under Geometry, click Delete Lower. Open the Dynamesh tab, change the resolution to 528 and click Dynamesh. Once this process is complete, you can Divide your mesh again. Stay under 5 mil.
Step 3: Basic Manipulation of the Art Cookie
1. Turn your model by clicking in the empty space off of your art and moving the cursor around, unless you want to start sculpting. Make the edge of the art visible, in preparation for the next step.
2. Find the Deformation menu in your tool palette.
3. We want to manipulate the Polish Crisp Edges slider and the Relax slider. Give each one a go just a little bit, as things can get silly looking really quickly. Polish Crisp Edges a few times, then Relax a little bit. Then you can Polish the edges a little more.
4. There are 3 small letters at the far side of the lower sliders: XYZ. Find Inflate. Click off X and Y. We want the Z! Now, slide the slider towards the letters a little bit. Find the Size slider and make sure only Z is turned on. Slide it towards the xyz letters and watch the thickness of your model grow. You can use the slider multiple times over and over if you are looking to thicken it a lot. I used it only slightly.
5. Play around with other sliders to see what they do, to achieve the look you want. Remember, each one has XYZ options and some of them don't look good on at the same time.
6. Press "9" to quicksave.
Step 4: The Sculpting Fun
Now I want to show you how to add some details and sculpt on your models by using the different brushes.
1. Press "B" on your keyboard to bring up the brush menu. There are a lot of options to chose from. Click "I" for Inflate brush. You can adjust the size and focal shift of the brush in the top menu, or by pressing the space bar, or by clicking on your pen button. The larger the size - the bigger the area you can affect. The smaller the size, the more details you can create. You can also hold down the ALT key to switch between add/sub option, which allows you to sculpt/add or to carve/subtract. Inflate brush is automatically in the add mode, so by pressing ALT you will be deflating whatever you touch.
2. Press "X" on your keyboard to turn on symmetry. You can also access symmetry options in the Trasform tab in the top menu bar.
3. Go over all the edges of the Shriyantra with the Inflate brush and make them pop a little more.
4. Go over the edges of the petals and inflate them a little bit too.
5. For texturing the Shriyantra, we're gonna use the Rake brush. Click "B" on your keyboard, then press "R". This should bring up the Rake brush for you. Use it to add texture to the triangles of the Shriyantra.
6. For the details on the petals, you can use the Inflate brush like we did with the triangles of the Shriyantra. There is a close up of the detailing I did in the pictures.
Make sure to quicksave periodically by pressing "9" on your keyboard.
Step 5: Adding the Bail to the Pendant
1. Select a cylinder in the tool menu on the right. Scroll down to Initialize and adjust the inner radius to make hollow tube out of it. Hdivide a few times, and make the cylinder shorter by using one of the sliders.
2. Click Make Polymesh 3D
3. Now go to the Subtool menu and click Append. Select the Shriyantra model from earlier.
4. While you cylinder is selected in the subtool menu, open up the Deformation palette and move the Size slider to scale the cylinder down. Make sure XYZ are all turned on.
5. Once you've scaled down the cylinder, go to the Taper slider and taper one of the sides. You can use the rotate slider by typing in the amount of degrees you want to rotate on the desired axis (X, Y or Z).
6. Now press "W", or click on the Move button in the top menu. Draw out the handle bar straight up while holding shift and click on the inner center circle, that should be white. Move the cylinder to fit right above the Shriyantra. We are setting it up centered and it will act like a bail on the pendant.
7. Under Geometry in the tool palette, click Divide 5 times.
8. Hold down CNTRL to bring up the Masking brush. Paint on a pretty clean mask with your symmetry turned on to a tapered point at the bottom on both sides.
9. Under Deformation tab in the tool palette, scroll down to Inflate and move the slider over to the right slightly to give it more thickness. This will make your masked are look sunken in and perfect for adding detail and texture. To inverse the mask and work on the sunken area, hold down CNTRL and click off your model just once.
10. In the unmasked area of your bail, use the Rake brush to add texture. CNTRL+click and drag to clear the mask.
11. Under Subtool, open up the Merge tab. Click Merge Down. This created a new version of the model with all the subtools Merged into one. You can access it in the main Tool Menu, above the Subtool menu.
12. Under Geometry - Dynamesh, up the resolution to 336 and Dynamesh this to make sure all the holes are closed. Click Divide to create a smoother mesh.
Step 6: Finalizing Files for Print
1. Under Geometry, open the Mesh Integrity tab. Click Check Mesh Integrity. Zbrush will tell you everything that's wrong with your mesh. :-O Delete lower levels of subdivisions and click Fix Mesh. This will make your printer very happy.
2. Open the Zplugin menu on the top. (You can click on the small circular icon to do dock this menu to your Tool Palette. That's where mine is showing in the pictures.)
3. Select Decimation Master and click on Pre-process Current Work.
4. Select the desired percentage of decimation. I want to make it within 1000k polys. I have mine set to roughly 8.45% at 320K polys. The key is to decimate as far down as possible while retaining as much of the detail as possible. So if you can go low - go low.
5. Click Decimate Current.
6. Look below for 3D Print Exporter menu. Click Update Size Ratios, select mm and one of the dimensions of your model. I want my pendant to be 5 cm wide, so I typed in 50 on the X. The rest of the numbers will adjust proportionally on their own.
7. Select STL, name your file and save.
Note: My file ended up being 16 mb which is within the acceptable limit at Shapeways which limits ya at 64 mb.
You're ready for print!!