Building a better nipple clamp

[Doctor Pervert]

I have a problem with many, if not most of the nipple clamps sold. They just don't work right.

Let me explain. There are some that work exceptionally well, clover clamps are one example but in fact they are in reality based on the old Japanese silk drying clamps. These work using a compound lever action to tighten the grip when you pull on the tab. This allowed a strong grip on the silk when it is wet and heavy and loosens as it dries and gets lighter.

So to recap, here are the most commonly sold and used clamps.



The first of these are the basic alligator clips with plastic covers on the jaws, most have adjustment screws like these to allow for varying pressure. Next are the tweezer style, again with platic coated tips and finally the venerable clover clamps. Yes, there are several more styles around including some screw type clamps, such as these but they are not ideal either.



The problem I have with all these is that they aren't made with the physiology of the nipple in mind.

Most use two contact points or jaws to clamp, in the case of the alligator and tweezer style this is especially problematic. The V shape formed by the jaws tends to be squeezing the nipple out as they close up. And this is the heart of the issue as I see it, none of them work to actively capture the nipple in an easy and simple manner. The two circular clamps in the second row of photos do address the capture part but are fiddly and tricky to use, especially solo.

What to do about this conundrum? Well as the proverb goes, idle hands are the devil's playground, and currently my hands are idle as I am on an enforced break from my travels and messing about in my workshop. More specifically I'm messing around with my 3D printer to see if I can solve this kinky engineering challenge.

Over the next few days (weeks?) I'll be posting on my progress and I'm interested in getting feedback and ideas as I go. I have already made up a few prototypes and I'm going to be sending a few to my local tester as soon as possible. I'm also happy to share STL files for these with anyone who has a 3D printer themselves to try out.

As a preview, here are just a few of the vertical designs I'm working on. These are meant to work with a frame to allow for nipple stretching, not all of these will make the cut but the process is illuminating...

 

[Dave47630]

Are you looking for something like this,

https://www.lowes.com/pd/Kobalt-Flex-Claw-Pickup-Tool/999957763

Maybe with more fingers. I think i have seen these with at least 6 fingers.

 

[Doctor Pervert]

This is kind of one of the ideas behind what I want to achieve. Of course these claw tools are big, heavy and a little too aggressive for many people.
What I am working on is getting a variety of jaw types for varying tastes but that all function in the same basic way. A quick clamp action that can be done one handed if needed in a small lightweight package.
I'll be posting a few photos of the first prototypes later today.

 

[Dave47630]

How about rubber o rings. It isn't a clamp. But I think it does what you intend. On the plus side, they take almost no volume. They could be worn and hidden under clothes.

Find a click pen that has a barrel as wide or a little wider than the nipple you want to clamp. Take the pen apart. You only need the point end of the barrel. Place the tip of the barrel into the ring and slide the ring, stretching it, down near to the wider end. Insert the nipple into the barrel. Slide the o ring off the end of the barrel.
You will have to experiment to find a good size of rubber o ring.
If you want a leash tread some dental floss into the large end of the barrel before placing it over the nipple. This may be useful when testing for size. Rings that are exceptionally tight may be difficult to remove.
With any clamp you must be watchful of loss of blood circulation. These rings go all the way around. They will trap blood easily. Be extra careful.

 

[Doctor Pervert]

Update:

Here's some of the first prototypes hot off the printer.


This is the triple jaw tweezer action design, the tapered collar is used to close them by simply sliding down. The jaws inward at the tips to trap and squeeze the nipple resisting slipping off.



You can see the serrated teeth on the jaws in this version for improved grip.



Also shown is the flat design, this I hope to make smaller so it sits flat against the nipple to be able to worn under clothes.

As you can see these are small devices, I'm currently using a plain PLA plastic for ease of prototyping but will likely make the final versions from ABS or PETG.



I intend to try various large sizes for the 3 jaw tweezers as well as shortening the arms to make them even more compact. More to come.

 

[Dave47630]

I like these. How many fingers can you have? 6 too many?

 

[Doctor Pervert]

It's certainly possible to double up the number of arms, really just a tweak in the design software. I'll give it try and see how it goes, the issue I have to watch out for is the jaw tips binding on each other, if they touch that stops them pressing in further on the nipple. That's why I settled on 3, just like the jaws on a drill chuck, 3 is good as it tends to centre the item they grip.

If I taper the jaw shape I can fit more into the same profile. There is also a trade off with surface area vs pressure, the more surface area the less pressure per unit of surface area. I am in the process of printing up a set 25% bigger than these first ones, it will be easier to see the capacity for more jaws on those.

I'm also trying to refine the flat design.



This again uses the 3 lobe method to trap the round shape of the nipple using the spring lever arm. I made this slide to adjust pressure but now I want to eliminate the lever arm parts as they stick out too far. For this to be a wearable it needs to be tight and compact.

 

[andrei]

would you please share the 3D print file?
I find clothespins rather old vintage and useless. I never got nipple clamps from the market, I know my wife would hate them. But I love your 3 point design.

 

[Doctor Pervert]

would you please share the 3D print file?

Sure thing, I'll work out somewhere like dropbox to post them so they can be downloaded via a link.
I have several other things I'm working on that are kink related so it's going to be worthwhile solving this sooner rather than later.

 

[Doctor Pervert]

Ok, so I've placed the STL files on my google drive, this is the link for access.

3D Kink items - Google Drive

drive.google.com

You will find 10 STL files, there are 5 variations on the small version and 3 of the large plus locking collars for both sizes. There is also a copy of this jpeg which shows what each version looks like. You will find the file names correspond to the jaw types and you can see them all in the image.



Recommended settings/options are as follows.

• Set adhesion options to "brim" as these have a habit of breaking loose due to being tall with a small contact surface.
• I use a 0.16mm layer
• I printed these using a genric PLA but should work with PLA+ and PETG, or even ABS

If you have any issues let me know and I'll attempt to work through them with you.

 

[andrei]

Thanks a lot for your files.
I am in a hurry and I will look later in my 3DS Max.

I was thinking today: why not using a screw nut? I know (for me) is hard to draw it accurately (I don't use engineering stuff like Autocad). But if the plastic is soft enough a nut can keep the "fingers" in place.

(Thinking of the Pear vaginal metal insertion found in the Insex movies, their new brand actually, just skips my mind right now)

 

[Doctor Pervert]

I've found the slide on collar stays put really well. Due to both being printed on the same plane the layers align which creates a nice amount of grip. You can hear them engaging as you slide it, it sounds similar to a zip tie when when you pull it closed.

Funny you should mention the pear, I have been working on various versions of those as well. I've made several prototypes including this one but without a screw thread so far. That's perfectly doable but requires a stronger plastic than PLA to work. I've found threads in PLA break really easily but will be experimenting with an ABS version soon.

 

[Doctor Pervert]

Getting some feedback from a tester, legs break off!

I can see where the problem is as they are all breaking in the same way, along a layer seam. I am in the process of redesigning the legs and making the joint more diverse to spread the force over several layers.
Once I confirm this eliminates the issue I will update the files on the link to the modified versions.

 

[Shwopen121]

Lol maybe something like these will work.

 

[Doctor Pervert]

Lol maybe something like these will work

Sure, there's a bunch of things that can be repurposed to work but the aim here is design something specificly made to grab hold of a nipple.

 

[Doctor Pervert]

Here's the update on progress over the weekend.
I decided that following the breakages on the original design I would redo the whole clamp so that rather than being a single print the component parts are printed separately then glued together to construct the final clamp.
This has a number of advantages as only the jaws change from one version to another.



This is the latest print run with several of the prototypes in the foreground. I even tried out a 6 legged version for @Dave47630 as he was curious about that.



As you can see the problem here is the jaw space becomes very crowded and consequently they don't close in tight enough as they bind on each other.



This is my first discrete parts prototype, the top collar was too big and there were issues with the legs not having enough bend in them so they were too close together in the unclamped state.



This is my current contender, I slimmed down the top collar as much as possible, I'd still like to make some more refinements there but am sending this version to my tester for eval.



Here is a close up of the 3 jaw types I have, from left to right you can see the point jaw, the smooth jaw and the serrated jaw. The point jaw is going to be pretty hardcore, I don't expect it will break skin but it is sharp enough to really dig in to the toughest nipples!

I'll be updating the google drive with these new files later today. For now I'll leave the original files up as well mostly because my testing with them has only been using PLA, I feel ABS or PETG will not suffer the same layer breakage problems.

 

[Doctor Pervert]

I have updated the STL files, the current version is composed of the following parts.

1. NC V6.2 Top.stl this the central point for the legs to attach to.
2. NC V6.3 leg.stl each set requires 3 legs
3. NC V6.2 serrated jaw.stl 3 per OR
4. NC V6.1 point jaw.stl 3 per OR
5. NC V6.1 plain jaw.stl
6. NC V6.5 lock collar

Note, you have 3 choices for jaw types. All jaws fit the V6.3 legs.

Slicer settings: I am printing these at 0.16mm layer height, infil set at 50% and bed adhesion is set to skirt. If you have any issues with adhesion try using "brim", this works fine but requires more post print cleanup especially on the legs.

Ensure you trim any excess from the leg ends before inserting into the jaws. Use Cyanoacrylate glue to fix legs into top and jaws. Ensure legs are fitted in the right orientation.

Google drive link

3D Kink items - Google Drive

drive.google.com

 

[subdream]

I wish I had a 3D printer...

 

[Charliebitme]

What would be a good way to get my hands on these if I don't have a 3d printer? Are there sites that'll ship prints if you've got the files?