Self Tightening Belt

[SMDave]

Hi everybody,
I am a tight belt enthusiast, I like the feeling of extreme tightness around my waist. I have had a lot of success using a ratchet strap, but I can't get it tight enough - not because I am too weak, but because I am too chicken!
So I was wondering about building a self tightening belt based on an electric winch such as this one:-
https://sherpa4x4.com/collections/front ... iler-winch
I would arrange it so when I push the button, it tightens to some specific length (such as 30 inches), waits a specific time (such as 15 minutes), then releases again.
Has anybody tried anything like this, or have any suggestions?
The idea is that I am too chicken to go down to 28 inches, so I would set this rig to do that automatically, gradually working my way up to tighter constriction and longer times.

[pavtron]

Just poking (exploring) this idea a little. So don't take what I'm asking the wrong way. Or read too much into it.

If you are too chicken to go tighter with the ratchet what makes you less chicken with the wench?

[SMDave]

The winch would be automated using an Arduino microprocessor or whatever. So once I push the button, it goes through a pre-programmed sequence of tightening over which I have no further control. I would also have my arms and legs tied down, only to be released once the tightening sequence has been completed. For example I might set it to go to 31 inches, wait 5 minutes, go to 30 inches, wait 15 minutes then release. Next time I would try 29 inches, then 28 inches and so on...

Have you tried it with a ratchet strap yet? They are inexpensive and available at most hardware stores.

[Shannon SteelSlave]

This idea kind of reminds me of that "New Belt" story by Mikel. Always loved the idea. The character in that story got more than she bargained for. I wish we could make that.

[SMDave]

Hi Shannon!
Please could you tell me where to find that story? I cant seem to locate Gromit's Plaza anywhere.
As to making the machine, it is pretty straightforward. Just the winch that I linked to, a low end Arduino and some simple software. Not saying that it is inherently safe - the winch can pull with 10,000 lbs of force, easily enough to kill a man. I measured the force on my Ratchet Strap, and it is around 350 lbs at the tightest I can stand it. But with enough safety interlocks it should be OK...

[Shannon SteelSlave]

Good to meet you Dave. I have permission to share this from the author himself :
https://www.selfbound.net/storieslr/newbelt.html

[Shannon SteelSlave]

Why not have a look at the Developers board? I think you'll fit in.

[SMDave]

Thanks for the link to the story - it is awesome! Of course one could not easily make a lightweight belt with sufficient power, but mine will be floor mounted and have plenty of power. Also I plan to use mine for 45 minutes rather than 45 weeks, but then again, so did the hero in the story...
Thanks also for the invite to the developers group.

[OrgasmAlley]

I do have suggestions, but they go in a different direction than that you are currently exploring.

I do not care for the combination of lots of power and a lack of absolute mechanical limit. I wanted to build a restraint system using compressed air and pneumatic cylinder(s), and came up with this:

https://orgasmalley.com/product/aircuff-systems/

The basic concept has substantial applicability to what you're doing. The AirCuff uses a small diameter cylinder that provides about 80 pounds of force at 125 PSI. It actuates by 3", which loops back such that the cylinder move takes this up twice, for 6". Since I found that to be insufficient additional cuff to easily insert a foot, the entire strap is doubled over the cylinder. It takes up 6" from each end, for a total difference from open to closed of 12". The maximum constriction is set by tightening a plate onto the strap, locking the two strap ends in position. You can set to an exact "closed" length, and the system cannot exceed it.

This type of setup has some advantages for what you're doing. Obviously, it cannot over tighten. By adjusting the air pressure, you can exactly control the force being applied. Using a needle valve, you could also very precisely set the desired rate of tightening. I don't know if you like the narrow constriction of the ratchet strap you're using now, but I could envision this pneumatic approach for either a narrow strap or something like a broad leather belt.

The most obvious source of compressed air is a compressor, but something like this can also run from a passive tank, spare tire, or even a modified soda bottle.

Hope that helps.

[SMDave]

Very interesting. I could use a set of these as a part of my system, thus avoiding the need to design them myself! As to the absolute mechanical limit, I will, of course, install such a limit if the winch mechanism does not already include it. I will also use a mechanical weak link for additional safety. Other safety systems might include:

Dead man switch
Backup release timer
Battery operation (to avoid power outages and shock hazard)
Opto Isolators between laptop and Arduino (in case the laptop PSU should go "live")
A current limit on the motor supply to limit the maximum winch force.
Maybe a tachogenerator and PID controller for the winch motor, if there is a way to install a tach. An electromagnetic pickup on the motor pinion might be one way to do this. The idea would give very smooth and precise control.

In addition, I will do several conservative runs with an assistant present to make sure everything works smoothly.

I have measured the force on my ratchet strap at about 350lbs at the maximum I can stand, so the use of an air cylinder is certainly a viable way to produce this. And, as you say, I could use a broad leather strap or perhaps even a steel corset on the actuator. I need about a 14 inch stroke, so that would be a pretty hefty air cylinder but not out of the question. The high compliance is also attractive, the system would provide a given force rather than a given belt length.

BTW, I LOVE your spanking machine. Did you see the YouTube video comparing your machine with your competitors? They cane a foam block and measure the depth of the indentation. Yours had quite a lot more power when set to 125 PSI, a 1 inch penetration compared to 0.375 inch for the competition. Of course we science geeks would just like to know the mass and velocity of the cane tip, but oh well...

Thanks for your input!

[TicleMeEndless]

You playing with death. That toy will press and crush your internal organs. Always has probablity of protection failure. Belt tightening must never be trusted to mechanism. Do it yourself or ask partner, and let's mechanism will block release.

P.S. Some lookslike situation was in movie "Saw 6", when two giant vises was supposed to shrink if humans in vises will breath. There the vise crushed the smoker's waist. https://youtu.be/zVJjasBMvrM
Revise and think if you want to be in his place?

[SMDave]

I like the video, what a way to go!
Always remember - safety third!

[Shannon SteelSlave]

Ok people. 'Round these parts, I am always on the side of safety. Dave is offering his idea for constructive criticism and a way to make it safe. He seems well aware of the danger, and offers the warnings with his posts that it is unsafe to do this without weak links and mechanical safety stops.
I think we are all aware that it is unsafe, but it is his "thing" so we should try to offer advice on how to do it as safely as possible. He is asking us for help. He wants to play safe and satisfy kinky needs.

I like the video, what a way to go!

How about how Dina Meyer went out at the beginning of "Saw 3"?

[bound_jenny]

Indeed, there should be work to build-in safety devices, failsafes, and other things to preserve life and limb.

Coming from a corset aficionado, I am acutely aware of the need for patience and gradual action when achieving a small waist. It can take months or sometimes years to reach that all too desirable wasp waist. Getting there too quickly is looking for trouble. I didn't go from a 26 to a 20 inch waist overnight (it took a few years). The innards need time to adjust to the new confines.

I'm quite sure that the "safety third" post was in jest. We don't condone reckless pursuits that could endanger life and limb (or innards). But we do encourage making any endeavour safe so that none of our members ends up in the newspapers under the "Odd deaths" column.

So any added feature that can quickly end a session if anything feels wrong, plus a companion to take action just in case, is commendable.

Thank you.

Jenny.

[OrgasmAlley]

Note the path of the strapping that actually tightens in my AirCuffs. You can easily get a full throw 4x the length of cylinder travel*, which would put your needs at a 4" stroke. A 2" cylinder will deliver 390 lbs of force with 125 PSI incoming air pressure. This is a very mundane cylinder needing only a basic air compressor. Note also that the system gives both a known force AND a specific terminal belt length.

* Consider a broad belt with a length of nylon strap running over it. Each end of the strap goes up through a common channel, like that in the AirCuff. They proceed together over a roller on the end of the cylinder, which actuates parallel to the channel, then back along the outside of the channel to be secured together. Extending the cylinder will take up four times its movement of the strap. 4" stroke nets 16" uptake in the strap, tightening the broad belt by this amount.

Thanks for the compliment on the SOM system. That's my video you're referring to. Both machines were using a mild steel rod of identical diameter (1/2", if memory serves) in this test. I cannot remember the exact lengths... pretty sure I matched them to the paddle lengths standard for both machines. The SOM would have been 32", I think. The Robospanker maybe 26"? They're long gone now. As to velocity... no way to measure that, but you could probably derive it from the video frames if you were dedicated