My First 3D BJD! (WALL OF PICS AND TEXT and a kinda guide)

SUPER TLDR; My first time working on a 3D doll and I wanted to make a quasi-guide for everyone that I would have liked to have when I was working on my doll, since it's hard to find anything specifically for modeling bjd's on the net and can be kinda hard to visualize the workflow if you're unfamiliar with the programs.

Howdy everyone!
Ok, so once again, I have shirked all my other projects for something else, lol. BUT this time I finished this one! This is my first 3D BJD and I'm so proud of myself for finally figuring it out and actually getting it done.
Anywho, here's the scoop: I started the actual base sculpt in Sculptris and Blender a millon years ago, but just picked it back up again to turn it into a doll via Blender. I'll let you know now that I'm probably the furthest thing possible from being proficient in Blender and I have to re-teach myself every time I use it so some stuff may look wonky to those of you who are blender gurus ^^U
For my own benefit and for the benefit of those interested I'll try to describe everything I'm doing in each picture to the best of my ability. Oh, and sorry the first couple of screenshots are kinda off kilter >>

For the uninitiated (like myself) here's a quick list of jargon I'll be throwing at you with super simplified definitions just so we're all on the same page ^^

• Geometry- This is the shape model itself. If I mention geometry, it will likely be to mention geometry of a specific part such as the arm geometry, head geometry, etc.
• Mesh- A model's geometry is made up of points, called vertices, and edges which connect to form faces (think back to 10th grade geometry). All of this together forms an editable mesh that you can manipulate to edit the geometry of your model. Low-poly models will have a minimal amount of vertices, edges, and faces but a detailed high-poly model (like mine) can have hundreds of thousands! You can keep score of my numbers if you look at the bar at the top of my screenshots :3
• Modifier- Modifiers are helpful functions that can be applied to your geometry (you can see the tab for them on the right hand side of some of my pictures). For this project I only used two modifiers, Boolean and Mirror.
• Boolean Modifier- This is a modifier has three different functions: Union, Difference, and Intersection.
  -Union permanently joins two separate geometries. I use this to join spheres to body parts to make the shape of my joints.
  -Difference (for lack of better term) hollows out a geometry using the shape of another geometry. I use this function for my doll's stringing channels and to form sockets. NOTE that when you use this function, at first it may not seem like anything happened, but you have to move or delete the shape you used to make the cut out of the way to see the hollow spot in your part. Kinda like moving a hole punch out of the way to see the hole you made in a piece of paper.
  -Intersection takes two geometries and gives you what's left of the geometries where they intersect. A good example of this is if you had a venn diagram and used intersect on the venn diagram it would leave you with the part in the middle where the circles of the diagram intersect. I really only use this function when I'm chopping up parts with a flat plane, since it acts like the difference function when used with a plane. I'll point out examples of all of these down in the pictures' descriptions.
• Mirror Modifier- Exactly as it sounds, this modifier mirrors a geometry across an axis/mutiple axis. I'll use this to copy all of my parts once they're done so I don't do more work than I have to XD

On to the pics!
OK! This is the original sculpt that I started off with, a kinda cat thing, lol. I sculpted the body and head separately in Sculptris and joined them together using Blender (which are both FREE programs, btw. sculptris is super fun and easy to use X3). The head also started off not having any ears since they were a pain to sculpt in Sculptris, so I made them in Blender and sent the head back to Sculptris to clean the ears back up. Sending stuff back and forth to Sculptris is something I'll do a handful of times during this just because for me it mimics sticking a joint on top of a part (Blender) and smoothing the sides to look good (Sculptris).



Here's the very beginnings of me chopping everything up and making individual parts. At this point I had a really vague idea of how I was going about cutting everything up, which in this case is:
1. In Edit Mode, I would select a specific part of my mesh and separate it from the rest of the model (CTRL+P) 2. I would then take a resized sphere (like the one to the left of the model) and stick it where I wanted it. In this pic it's at the top of the arm and leg. 3. Use the union function of the boolean modifier to join the sphere and the part. 4. take my newly formed part and use the difference function to form a socket in my torso part. In traditional sculpting this would be like taking some clay and forming a ring with it, squishing it in your socket, and then using your ball joint to shape the socket. This is the only time I really select a part from the mesh itself and separate it as opposed to using a plane to cleanly cut the part off. See how jagged the torso is where I separated the leg?



This picture you can see where I chopped the head off, added a ball on the neck, and formed a rough hip socket. The lines inside the socket are from me rotating the leg and using the difference function multiple times so that the leg has room for full range of motion. In the next picture you'll see that my legs are deeper than they are wide, giving the joint at the top of the leg an egg or football shape, so I had to make sure that when my doll goes from a standing to a sitting position, it has room in the hip socket to do so :3 Note that you can still see where I joined the ball joints to my parts in this picture. To fix this I'll import my model back to Sculptris and smooth out these spots since that was the most natural thing for me. I'm sure there's a way to do this in Blender and I could have avoided this problem from the beginning, but I had no idea what I was doing X3 Don't worry, my process gets cleaner and better >>



Yay! Smooth joints and my first pic from the side of my model. One thing to note about Blender is that there are two different views when you work on something like this, ortho and perspective (found in the View tab at the bottom of the page). I work strictly in ortho since perspective skews your perception of your model and the proportions will be thrown off. Perspective is good to use if you're animating, or if you just want a quick look of how your model might look IRL.



Still working in ortho view, just moved around a bit. BIG TIP use middle mouse button (aka click and hold your scroll wheel) to zoom your camera around your model and use SHIFT+middle mouse button to move you camera so that you have the same view but the camera move up, down, left, and right. Anywho, I chopped up the elbow and knee, added a knee joint, and added stringing channels to the thigh and shoulder. You can see how clean the cuts at the knee and elbow are because I used a plane to cut them. At this point I was deciding whether to make double or single jointed knees and decided to go with single joint but to cut a good bit away from the thigh so that the knee would pose further. I honestly didn't want to deal with a double joint at this time since this is still my first 3D doll and I'm going to have to mod the knees anyway. With the way I jointed it, it'll probably buckle easily, but we'll see.



Butt XD This is to show off the back of the knee, neck joint, and where I cut out the back of the thigh. Notice that I have to manually rotate the leg parts to form my sockets. When I'm doing this, it's very loose and sloppy (I'm sure) and will take a LOT of clean up when the doll is printed, but I anticipated that. Someone with better working knowledge of the program (or CAD programs in general) would probably be able to parent/child the parts and turn on collision to make sure good mobility and posing is a thing, but I'm just going with what I know of bjd's (which is a heck of a whole lot more than this XD) and will deal with logistics later when I have a physical copy to play with.



Arm joints! Since I'll have less-than-ideal leg movement and the torso will be one piece, I decided to give the arms awesome movement with a swivel joint in the upper arm. This is one of those cases where I'll have to do extra clean up when I print. Look at the bottom half of the upper arm and you can see the cylinder going up center where the stringing channel is. Originally I wanted this to be just a flat area inside that part but I screwed it up early on and it was too much of a pain to remove that part after the fact, even going back in with the difference function. But it's not a big deal, I'll just sand it down later if I decide I still don't like it.


Cont. in next post!

 

Here you can see all the other stuff I've jointed thus far. The main things I wanted to show in the pic was the shape I used to make the stringing channels on the top (?) of a joint, how I positioned everything to work on the legs, and the shapes of the ankle and upper arm joint. I use the rectangular (it's actually a flattened cylinder) geometry in the middle of the page, place it where I want the channel in the lower leg part, then use the difference function on the lower leg part. It makes more sense when you're able to do it yourself >>




There's that plane I keep talking about! I'm ready to work on the torso and head now that my arm and leg are fully jointed. I know I said I was only working on one side at at time, but I cut off the un-jointed arm and leg so could visualize what my finished body would look like. It just made more sense to me even though I really didn't need to do it. >> Ok so let's talk about difference and intersection when cutting with planes. In this situation, if I use a plane to cut a leg in two (which I did), if I place the plane at the knee where I want the cut and press difference, only the top part of the leg will be left, if I press intersection, the bottom part will be left. There's a long explanation of why this happens that I won't go into at the moment, but because of this, when you cut with a plane, you will have to make two copies of the part you're cutting so that you don't lose half of it when you apply your modifier.



Time to chop up the head (and not sound like a murderer lol). I used a plane that I manipulated to to separate the head back from the faceplate and went in with another modified sphere to hollow the head itself. I decided a faceplate system would work the best for me so that I wouldn't have to recreate the neck hole every time I wanted to make a new face. The squished sphere in the middle is what I'm using to cut out space for the eye wells. I didn't go all the way through the eye because I wanted to cut that out manually once the face was printed so that the shape of the eyes didn't get messed up.



This pic you can see the eye well I hollowed out, the little notch I added for the s-hook to rest in the neck hole, and also a small slat to try and keep the faceplate on the head back when I print. In the next few pics you'll see that I get rid of that idea because it got destroyed when I added my mirror modifier. Speaking of which, that's why the head is so ugly and uneven, no use in doing double the work when you have modifiers :3



AHH WE'RE GUNNA BE EATEN. I'm sorry, it's late out. Anywho, to apply a mirror modifier effectively for this situation, I had to go into edit mode and delete half of my mesh, so that the other half can be, well, mirrored. One big problem with doing this with high-poly models with crappy topology (the way the faces, edges, and vertices are arranged) is that edge where the two halves of your mesh will be joined will be uneven, so I have to go in and manually straighten a lot of the edges so that I can try to patch the two halves together soundly. The best way to do this without going bananas is to select all of the edge loops (a bunch of edges grouped together) on the open part of your mesh, press S to scale, click middle mouse button so that you're scaling to the X-Axis (red line) and then hit the number 0. Does it sound convoluted? Absolutely. Will it save you from the soul crushing task of trying to do this manually? Absolutely. Though once you do that, you're good to go if you apply your mirror modifier, just don't forget to check the Clipping option so that anything you may have missed joins together in the middle.



Let's talk about the mirror modifier for a second since I went over the boolean modifier. If you find that you apply your mirror modifier and it doesn't flip the "right" direction, the main reason is probably because the origin for your geometry is located in the wrong place. What does this mean? Have you noticed the tiny orange dot that's in every picture? That's the origin, each individual geometry has its own. The geometry revolves around the origin, thus if it's placed wrong, it can cause the mirror modifier to do wacky things. The easiest way I've remedied this is to 1. Select whatever part I'm working with in Object mode, 2. Go to Mesh< Snap< Cursor to Center, this will move the 3D cursor (not your mouse, but that little cross hair) to 0,0,0 on your grid, 3. Then all at the same time hit Shift + CTRL + ALT + C which will bring up a menu, select Origin to Cursor. This should place the orange dot in the center of your grid and allow you to mirror across the center of the grid. I end up doing this for every part I made when I mirrored it, but you can also use this trick to place the origin back on your geometry if you just want to rotate the part. For that you can just go to Mesh< Snap <Cusor to Geometry or click to place the 3D cursor (the little crosshair thing) anywhere you want your origin and to Origin to Cursor.



Now we have an even, lovely headback and faceplate One thing I do need to warn about when using the mirror modifier with such a high-poly model is that there is a high chance of Non-manifold topology. Without going into detail, this usually means that there's a hole in your mesh or there's random floating edges or vertices. Essentially, your geometry isn't "watertight." More than likely you'll have to go in and manually clean this topology up but that's easy work to me compared to not using a modifier. Non-manifold topology can be impossible to spot, so the best way to find it is to 1. select the part your working with and go into Edit mode with Vertices visible. I also like to have the see all option selected so that I don't miss anything on the inside of my mesh. 2. Press A on your keyboard a couple times to make sure nothing is selected (nothing should be highlighted) 3. With nothing highlighted go into Select < Non-manifold. This should highlight everything that is non-manifold in your mesh. The important part here is to make sure you have the select vertices option selected and not the edges or faces otherwise the non-manifold option won't show up in the Select menu. Once that's all done I just go through each section of non-manifold vertices and correct it, unless it's something deliberate like an arm hole or neck hole that I know I'm going to work with/fill in later.



I went through this process for the faceplate, headback, and body. The more I did it, the less of a pain it became, plus the headback wasn't too bad since it has simpler topology :3




Con't in next post! Don't worry we're almost done!

 

Alrighty we're in the homestretch! All that's left is to apply your mirror modifier to all of your body parts and to separate the parts from each other. If you remember, to do that you 1. Select your mesh in Edit Mode after you've applied the modifier, 2. make sure everything is unselected, then only select one of the parts you copied (i.e. if you mirrored the feet, only select one foot) 3. then use CTRL+P < Separate to separate your parts. If for some reason you need to join parts together you can use CTRL+J to join two or more geometries so that they become one mesh. You may also have to rotate your mirrored part to make it look like the original if the original part was rotated. You're smart, you'll figure it out





And now we're all done! I have 21 parts total and waaay too many verts haha.





Thanks for sticking with me this far if you've made it! I hope this helps a little bit for anyone who might have been intimidated by making a doll in a 3D program like Blender. Honestly once you get in the flow, it's just a lot of tinkering and repetitive motions, so it's not too scary

 

Anna, thanks a ton! I'm glad this helped a bit ^^ And yes, I actually spent like at least 2 hours figuring out why I wasn't able to import back to sculptris the first time I tried it, but I was able to figure it out.
There's 3 main reasons for my particular situation:
1. Sculptris can't handle anything that's not tris, so you have to convert all quads and n-gons to tris.
2. Any one vertex cannot be connected to more than 24 edges. This was big for me since I used 100x100 spheres for my joints and the points where all those segments connected definitely had more then 24 edges connected, lol. I was able to find an easy way of finding these points. Basically you create a cone with 23 segments (as opposed to 24, just to be safe), ctrl+j to join it to the part your looking for those trouble vertices, highlight just the vertex on top of the cone and hit shift+g < connecting edges. In your options on the left you should be able to set the select to equal to or greater. This will select all vertices in your mesh that have 23 or more connecting edges so you can manually go in and fix it.
3. If all else fails and sculptris is still yelling at you, go back and make sure your geometry is manifold and you remove redundant vertices, which you can select your mesh, go to your tools on the left, and click remove doubles. If all THAT doesn't work, then maybe sculptris just has something personal against you XD

I hope all that made sense, lol.

Thanks! It was so late, I was hoping it all made sense when I was done XD And yes, sculptris is infinitely easier and less convoluted, especially if you have a wacom tablet or something similar to work with. Even if you don't, sculptris is just so intuitive that it's easy to pick up even if you use a mouse. The only reason I would prefer blender over sculptris for sculpting is that you would probably have neater topology and would probably be able to have a more precise sculpt simply because you could enter number values for anything, but honestly, if I wanted to do that, I would just start with a box model in blender and not even bother with sculptris. X3