A really nice titanium chastity cage from someone like Evotion can easily cost $3,000. Designing a really nice chastity cage like something from Evotion will take a year of learning CAD techniques and will likely spiral into a huge hobby that will take over your life and at least one room in your house. And eventually you'll get around to making that Evotion cage.

This subreddit is for those who are deep into that rabbit hole or who are curious about why people keep vanishing down that hole. Sit down. Have some tea.

Software

First of all, most of us use parametric CAD. What is that? That's CAD based on a series of steps... make a 40 mm circle now take that circle and turn it into a 50 mm tall cylinder. Change that 40 mm circle into 38 mm. Now the cylinder recalculates to be 38 mm in diameter. There are other flavors of 3D modeling. u/Kotomimaru who makes the tentacle cage is most likely using subD modeling where they define lines and curves that pull at the ultimate surfaces of the cage. You can make some incredible designs but you can't go back and change that 40 mm into 38 mm. There are other types of modeling as well and there are tools that combine multiple approaches. But this isn't a wikipedia article.

Anyway, this is by no means an exhaustive list, it's just the ones I happen to know a thing or two about.

TinkerCAD

Free online CAD software. It's fairly limited in its capabilities compared to full blown CAD applications but it's where many of us started and you can make a working cage using it. You'll want to quickly move on though once you get the concepts — becoming a master of TinkerCAD means you're really good at doing things the hard way.

Fusion360

Modern CAD application, fully featured with parametric modeling but also subD.

OnShape

Web based like TinkerCAD but fully featured. Focused solely on parametric workflows with excellent version control.

OpenSCAD

CAD as code, open source. No sketches, no dialog boxes. Just code. Very powerful but takes a lot of effort to learn.

FreeCAD

Fully featured and open source. Primarily parametric modeling but also supports direct modeling.

Blender

Open source. It does anything but parametric meaning it has only the loosest understanding of dimensions. You can make amazing designs in Blender, designs that would be next to impossible in a strictly parametric tool. But if your ring is too small, you'll need to start over (kind of... maybe... it's complicated). I'm guessing the Tentacle cage was done in Blender or one of its commercial competitors like Rhino or Maya.

Rhino

Not free at all. It's about $1,000 but I'm excited learning it with the trial version so I'm going to mention it anyway. And I'll probably buy it. It's primarily NURBS-based surface modeling but also has subD and direct modeling as well (again, I'm not wikipedia), but Grasshopper, a native plugin for it, gives it interesting generative parametric capabilities. Grasshopper is like OpenSCAD meets geometry nodes.

Where to Learn

You can try YouTube videos. It's all out there. But it's scattershot. I find paying for a Udemy series or something similar is a far better use of my time. I have an old video tutorial on my Substack as well — it'll get you started but I've learned a lot since then too. Maybe I'll do another some day. I like to teach.

Printing at Home

If you're designing cages, you'll likely want a printer to at least prototype with even if you don't plan on using it for actual devices. Being able to have the design in your hands an or two after you finished the model is invaluable. But the KD of KINK3D made the Cobra and Viper without an at-home printer so I guess it's not a requirement.

FDM

Inexpensive FDM printers can be had for less than $300 and can make cages out of popular plastics such as PLA and PETG. Enclosed printers are necessary for ABS, a popular plastic for people wanting to vapor smooth (do your own research on skin safety). Prints made from FDM printers will have microcavities and will take significant post processing (sanding) to be something of commercial quality. But RoosterCage uses FDM printing so it's certainly doable.

SLA

SLA is another option but is far more advanced, requires significant ventilation (ideally somewhere not attached to the home), PPE, and a lot of research — most resins are not skin safe, even after curing.

Print Services

There are numerous print services — a simple google search will bring up quite a few. Many of them are platforms that connect you with individual printers — sometimes people with a printer in their garage, sometimes a company with 200 employees. Prices will vary wildly between some of the various print shops out there. Besides the technologies available to home printers, other more industrial technologies are available. Typically you just upload your model, select the technology, and you get a price right there.

But won't they recognize it as a chastity cage?

Yep. But I bet you anything prints shops don't have a Bring Your Kid to Work Day because I'm sure they are printing sex toys all day long (dildo, dildo, butt plug, dildo, hey, a chastity cage, butt plug, fidget spinner, dildo). Listen, I have had back and forth emails with the owner of a print shop about a quality issue and skin safety. I used my real name. I didn't say "chastity cage" but he had the model, he could see what it was. Just keep it professional and they will too if you even do need to ever speak with them — you seldom or never will. For example ask "are your dyes safe for long-term non-mucosal skin contact?". Don't ask "will the dye hurt my locked clitty?".

Ok, so onto the technologies...

SLS

This involves using lasers to melt micron-sized nylon beads. This is how Cherry Keeper cages are made. Great for white cages. All other colors involve dyes.

MJF

This is a patented HP technology that also uses nylon but has better dimensional accuracy than SLS and better strength (or rather the strength is isotropic). But the prints are naturally gray.

Prices for SLS and MJF prints vary wildly by vendor but you shouldn't be paying over $50 with vapor smoothing. Although single-unit shipping will get you.

DMLS / SLM

These technologies are similar to SLS except instead of nylon they are using 316L stainless steel or titanium. This is how BAWR's BD series cages are made as well as Evotion's. There are only a few vendors out there and they are mostly in China (no, Evotion and BAWR don't have one of these machines — they use the same vendors you would use). Prices for a full cage in titanium will cost around $200 depending on post processing and mass. Some vendors will quote $700. Go somewhere else.

Post Processing

The professional print shops will usually offer some sort of post processing. That may include vapor smoothing for nylon, polishing for metal (no one does anodizing for Ti that I've found), heat set inserts for security screw lovers, sand blasting, screw tapping, etc. For anything involving taps or inserts, you'll usually want to include a drawing. Most full-featured CAD applications like OnShape or Fusion can generate one.

Drawings

Especially if you're working with a SLM shop, include a drawing as they are used to working with engineers. It will show them how parts are supposed to fit together so they understand that when they are polishing. But they'll want drawings showing any taps or heat-set inserts also. If your modeling application can't do drawings, a simple screenshot with some marked up annotation will work too.

Before long, you'll know exactly what Ø3,4 ↧ 2,6 ⊔ Ø6,5 ↧ 1 means.

Special thanks:

While KD of KINK3D didn't teach me CAD, he spent some time with me and got me thinking about a better way to organize my models. I learned a lot in that afternoon.

Other resources:

There's of course r/3dprintedchastity but I created this space because that place was a bit too porny for my taste — I drew the line when I saw a guy bouncing on a dildo that wasn't even 3D printed. But there's also places like r/Onshape, r/Fusion360, r/3Dmodeling, r/3dprinting, r/resinprinting, etc (sadly, r/CAD is still private from the Reddit mod protest). My experience in engaging with these communities where I have to show explicit models (tagged NSFW) is that 95% of the comments are jokes but a few people will give me actual advice.

I know some people here know this crap better than I do but they don't like to write like I do.

If you want a metal cage, there's only three metals you want to consider. And if it's made from one of these three metals, it will 100% say it. If it doesn't say it, I promise you it isn't.

304 stainless steel. Many of your ~$30 commodity steel cages coming out of China are made from this. It's what your pots and pans are made from. It typically won't rust but I wouldn't build a prop for an ocean liner out of it. If you know you have a nickel allergy, you might not like it. Most Ternence cages are 304.

316L stainless steel aka medical grade. This is what steel surgical equipment is made from I believe because it doesn't bother those that have a nickel allergy. Now, it actually has more nickel but the nickel isn't bioavailable like it is in 304 so your body doesn't see it. I believe this is also marine stainless steel — it's much harder to get it to rust. I don't believe I've ever seen this in a commodity cage, only in custom cages. So yeah, if you have a nickel allergy you just went from $30 to $300.

Titanium. About 60% the weight of steel which is significant (but still 4 times denser than the nylon that's so common in many plastic cages). Besides sounding Iron Manish — ironic given that steel is the one with the iron content — it's not going to have any real advantages strength-wise, at least not for our application, it's just lighter. But the real cool thing about it is you can anodize it so you can get lots of neat colors. These will fade over years as it is a surface effect but it's still cool. You seldom see it outside of custom cages and it usually starts around $500 unless you want to go with a few disreputable Chinese vendors then you can save a few bucks (not referring to BAWR here — he is very reputable). Btw, the only vendors I know anodizing are Steelwerks Extreme ($$$$) and Badass Workroom ($$). Evotion ($$$) doesn't and I don't think Steelworxx ($$) does either. And that about rounds out who I can think of off the top of my head doing titanium.

Shit to avoid:

Anything else. Seriously. 304 is inexpensive enough that if it doesn't say 304, move on. I don't care how cute it is. I've sampled one of those cages just for shits and giggles and I don't know what that thing was made out of but the only thing it had in common with metal was that it reflected light.

Dishonorable mention: Titanium Steel. There are some crap vendors out there selling custom cages made from "titanium steel" for $200 – $300. There's no such thing as titanium steel. It's a bullshit marketing term from the jewelry industry for 316L where they are basically trying to tell you it won't give you a rash from nickel. Well, in jewelry, no one will feel the difference between 316L earrings and titanium earrings. You will in a chastity cage.

Top plane (I like my penis going through +Z). Looks good so far, right?

https://preview.redd.it/nxdzbep7umwg1.png?width=1236&format=png&auto=webp&s=d6391b88826667d4f148e88b8b09665388200c43

Let's look at the right plane.

https://preview.redd.it/12uvdzujumwg1.png?width=698&format=png&auto=webp&s=98609ea0934da82a0f5a23b74688a6750bd47797

Derpity derpity derp. Anyone see what I'm doing here? Got my nice curvature going on, my preferred 10x4 mm cross section.

https://preview.redd.it/d4rqkswxumwg1.png?width=506&format=png&auto=webp&s=08bbbb772ff7db485deab7507203f9a61955d055

Nice little curve to sweep my profile through.

Throw on some fillets and voila, a 43.435 mm ring, but 4.5 mm smaller than I had intended. Holy crap. That's like an entire Amazon ring size down.

https://preview.redd.it/27p3iyj9vmwg1.png?width=740&format=png&auto=webp&s=163ca416fc615e5901e9b69a0548e9f950e50133

Amazingly I can wear it and I have been wearing it. Since some time in the middle of last year. With a 38 mm flaccid shaft.

But yeah, I'm an idiot. Now when I do these designs, I don't dimension the circle. I dimension this first (the 1.5 mm is for the fillets):

https://preview.redd.it/kyb5nuglymwg1.png?width=510&format=png&auto=webp&s=452dd57d5d3737bd4fc77f9ec0ff762fe8a879ba

And I don't sweep, I loft otherwise the cross-section at the top won't be flat.

Why the 12 mm? I just like some geometry that isn't curved. Makes things easier when doing the junction if I have something that is flat.

https://preview.redd.it/m0lpgsw3zmwg1.png?width=604&format=png&auto=webp&s=7e569102a29d4a8810d18a476f6a5e79095a3d44

So, what's my point — besides being a nice little ring making tutorial (I doubt anyone reading this subreddit needs one) — it's a hey, check your measurements occasionally. That 48 mm on the sketch may not result in 48 mm real geometry because you're not nearly as clever as you know you are.