Compact Spanking Machine

Ideas and instructions how you can make your own bondage toys.
SMDave
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Compact Spanking Machine

Post by SMDave »

Hi There!

My spanking partner was stuck out of state for a while, and I was getting desperate so I built this spanking machine to use until she returns. The main thing is the compact size, it simply bolts to the metal frame of our queen sized bed. I simply drilled two extra holes in the frame, which are usually covered by the bedding. This gives a secure base for the machine without having to store any large and suspicious looking contraptions around the house. It bolts on in about two minutes using an ordinary wrench.

This was only a one day build using stuff from the local hardware store. It is powered by a 1x7x0.135" tension spring obtained from Lowes Hardware. The release mechanism is just a gate latch. It is shown with a single spring, I can fasten up to three springs if I want. However, just the single spring gives a very intense blow that is as hard as I need it, and I like my whippings harder than most. No noise from motors or compressors, just the sound of the swat itself. I have experimented with various end effectors, the riding cop shown seems to give the best sting so far. A dressage whip works pretty well also. The end effector simply unbolts using two machine screws (2" number 10). The thin lanyard visible on the floor is what I pull to release the whip.

This is an inexpensive and readily available way to make a spanking machine, I only had to use ordinary hand tools and a few power tools that I already had at home. Maybe I will be inspired to make a Mk II, using a torsion spring for higher tip velocity, a motor drive, and an Arduino controller. A torsion spring works better because very little of the stored energy is wasted as kinetic energy in the spring, but the hardware store didn't have one. McMaster Carr has them though, and will even wind you a custom spring if you need it.

But better yet to be reunited with my lover!

Dave
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kinbaku
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Re: Compact Spanking Machine

Post by kinbaku »

Do you activate it by manually pulling the rope and then releasing it?
Or do you have to re-tension and hook it by hand each time and disconnect it afterwards by pulling the rope?
SMDave
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Re: Compact Spanking Machine

Post by SMDave »

Re tension and hook it by hand. Pulling the string releases the spring. Takes about 10lbs of pull, and the powerful swat comes immediately.
I have found a better end effector - a length of 1/2 inch diameter G10 glass/epoxy composite. My lover is a tennis champion, and she generally gives me 10 swats full force using a sjambok whip. I can only take about four swats from the machine using a G10 rod. I call it the Serena Simulator (after tennis champion Serena Williams)!
The basic machine could be automated without too much trouble, I was just in a hurry to get something working using local materials - necessity is the mother of invention! If somebody else wants to build one I would suggest ordering three springs, the one I used plus a weaker one and a stronger one. You have to send off to an industrial supply house for such springs, but the place I use delivers in 24 hours. A used power winch would be a cheap and effective way of cocking the spring.
https://www.ebay.com/itm/USED-X-BULL-45 ... SwXO5fTl6Y

For a fully automated machine I would suggest a numbered knob to set the tension, and a button to release the spring. The spring would automatically re-cock after each stroke, then pressing the button would release the next stroke. That way there is no whir of the motor preceding the stroke. The spring tension goes up to 11, of course.
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kinbaku
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Re: Compact Spanking Machine

Post by kinbaku »

SMDave wrote:Re tension and hook it by hand. Pulling the string releases the spring. Takes about 10lbs of pull, and the powerful swat comes immediately.
Thanks for the explanation.
SMDave wrote:I have found a better end effector - a length of 1/2 inch diameter G10 glass/epoxy composite.
You can also use a Delrin rod, see viewtopic.php?f=12&t=11544
SMDave
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Re: Compact Spanking Machine

Post by SMDave »

For the tech heads out there - the spring has a force of 90 pounds and a stroke of four inches, for a stored energy of 20 Joules. I am guessing that around 50% of this ends up in the cane itself, the rest is lost to friction and kinetic energy of the other parts. 10 Joules does not sound like a lot, but the very most I could take this morning was 5 swats!

Anybody know where I could purchase a big torsion spring? The only one i can find is a garage door spring, which is TOO big. I need something about 6 inch diameter made of 3/8" diameter music wire.
Thub56
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Re: Compact Spanking Machine

Post by Thub56 »

McMaster carr always has your back for mechanical stuff. https://www.mcmaster.com/torsion-spring ... springs-5/
SMDave
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Re: Compact Spanking Machine

Post by SMDave »

Thanks, Thub56!
Unfortunately McMaster doesn't sell a spring anywhere near this big, but they WILL wind me a one - of custom spring, for a price. I have not yet gotten a quote, though. I did find a couple of springs that are too large for my personal taste in spanking, but are inexpensive and off the shelf.
https://www.easternmarine.com/right-han ... -08-606-rs
https://www.easternmarine.com/pj-lh-tor ... ing-180402
An advantage of the torsion spring design is that I don't need an end stop as I do with a tension spring, which adds to the mechanical complexity. I used a self adhesive felt pad to absorb any excess spring energy, but I don't know how long it will last. Easy to replace, though.
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Re: Compact Spanking Machine

Post by rmcingle »

This reminds me of a fantasy I had, and which I had started to write a self bondage story about but never completed.


In my fantasy / story there was a similar spring loaded spanker. The 'spankee' would be strapped down and locked in place using an electro-magnet, bent over a frame. The spanker had a micro-controller that monitored the operation, and include a countt that could be set to some number, and when it reached zero it would release the electro-magnet securing the spankee in place. Thus, the 'spankee' had to pull the cord that operated the spanker repeatedly in order to obtain release.

A feature that my fantasy device had was that there was another, small electro-magnet that engaged the spanker. When the spankee let the cord out, the electro-magnet would slide back towards the spanker and engage a metal plate. The spankee would then pull back on the cord, winding up the arm. A simple rotary shaft encoder connected to a small microcontroller would then release the small electro-magnet when it was appropriate. If the spanking was intended to be mild it would release early in the stroke. If it was intended to be severe the spanker arm would need to be pulled all the way. Or, it could be set to random. Perhaps the number of swats would also be a random number.

Add a web cam, give remote access to the microcontroller via the Internet and a Master/Mistress could punish their slave remotely

R. Mc.
SMDave
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Re: Compact Spanking Machine

Post by SMDave »

Yes, that would represent the ultimate development of my machine. Right now it is in a very crude form, yet still provided the stimulation I craved so much. Interestingly, if it is operated by an electric motor rather than a rope pull, a pair of AA cells would provide enough energy for some 900 really hard swats! I guess all that this means in practice is that battery life is not an issue. The processor would take more power than the spanking motor. And it is never wise to plug such machines into a wall receptacle, for electrical safety issues (insulation can fail).

P.S. For the tech heads, each Duracell Coppertop AA cell can provide 0.2 amps at 1.25 volts average for 10 hours, which works out at 9000 Joules. Each swat takes only 20 Joules.
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Re: Compact Spanking Machine

Post by SMDave »

Spring_Tensioner.JPG
Here is the progress so far:
The whip attaches to the part of the spring sticking out. The motor is on the left, and the actuator on top releases the spring. Mechanical assembly is now complete, I just have to wire it up, debug it and paint it. It is controlled by an Arduino processor, and the software is written but not yet fine tuned...
It was designed using FreeCad, and the motor runs at 40 RPM but will do less than a single turn in its lifetime. The blue thing on the right is a potentiometer to sense the shaft position. In use, it stands vertically with the motor at the bottom. I can set the power and number of strokes then just hit a button to make it run. The spring holds 50 Joules of energy, which should be plenty. I doubt that I will be able to take even a single a stroke at full force, even though I have a "leather butt"!
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Re: Compact Spanking Machine

Post by bound_jenny »

SMDave wrote:Here is the progress so far:
That's a very impressive-looking machine. Very well designed industrial look.

Nice! 8)

Jenny.
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kinbaku
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Re: Compact Spanking Machine

Post by kinbaku »

Nice work, SMDave. :hi:
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Karren
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Re: Compact Spanking Machine

Post by Karren »

Very impressive! I once made a spanking/boob slapping machine out of a 1x10x16 inch board with a long screw 3/4 way down the long side. Then the screw head inserted into a variable speed power drill. Set the drill in a vise and plug it in. Set about 30 revs per minute it would slap my breasts raw in a couple minutes.
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bounddosster
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Re: Compact Spanking Machine

Post by bounddosster »

Karren wrote:Very impressive! I once made a spanking/boob slapping machine out of a 1x10x16 inch board with a long screw 3/4 way down the long side. Then the screw head inserted into a variable speed power drill. Set the drill in a vise and plug it in. Set about 30 revs per minute it would slap my breasts raw in a couple minutes.
also acted like a fan to cool your burning breast?
That's my excuse and I'm sticking to it.
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Karren
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Re: Compact Spanking Machine

Post by Karren »

bounddosster wrote:
also acted like a fan to cool your burning breast?
Under boob sweating is a real thing! Lol.
I reject your reality and substitute my own….......

My Kinky Photos —— https://ibb.co/album/n30dgX
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