Spank machine question

Ideas and instructions how you can make your own bondage toys.
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Lexx
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Spank machine question

Post by Lexx »

Hi, do you think it's possible to make a spank machine using these servos?

https://aliexpress.com/item/32240916087 ... Adapt=glo2
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Riddle
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Re: Spank machine question

Post by Riddle »

Those servos are not really strong enough for a decent spanker. Need a strong electric motor to get decent power. Most spanking devices use a spring for the spanking power and a slow geared motor to pull the paddle back.
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rmcingle
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Re: Spank machine question

Post by rmcingle »

I agree with riddle: no way that a RC model servo is going to make a decent spanker.

Keep in mind that a servo is generally rated in its torque, and not necessarily its speed. It is easy to trade speed for torque, that is just a gear ratio. Want to double the torque, just gear it down, except it now turns at half the speed.

Those servos advertise imply an impressive torque, but they leave out an important part of the specification. Torque is a measurement of a force AND the lever arm.

Medium torques, such as you would apply to tightening a bolt, is generally measure in "Foot-pounds" or "Newton-Meters". One foot-pound of torque is what you get when you have 1 pound of weight hanging on a 1 foot long lever (the wrench). If you put the same weight two feet out, it provides two foot pounds of torque.

Small amount of torque are often measured in ounce-inches or kilograms-centimeters.Looking a little further down the specifications I did find where they say it is kg-cm: There are 2.54 centimeters in an inch. So, if you wanted to swing a paddle that was 1 foot long, it would be 12 * 2.54 = 30.48 centimeters to the tip.
A kilo is roughly 2.2 pounds, so that kg servo could lift 2.2*60= 132 pounds, but only about on a 1/2 inch lever. Divide that 132 by 30.48 and you can see that 4.3 pounds applied at the tip would stall that servo.

The specifications also list a fairly impressive speed of 60 degrees in 0.15 seconds. I suspect that is unloaded, however, and it would be a lot slower pushing a heavy torque.

I suppose it would be an interesting study to find out just how fast a paddle is traveling when it strikes your ass. Anyone want to set up a high speed camera and film against a calibrated backdrop to measure the speed of a hand, paddle, crop, etc?

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Re: Spank machine question

Post by ubnt »

I think 60º per 150msec is not fast enough for a whipping or spanking machine. Maybe an automotive wiper mechanism is a better alternative.
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Shannon SteelSlave
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Re: Spank machine question

Post by Shannon SteelSlave »

A wiper motor could possibly work, but it still needs something to load up tension, and release at the correct angle.
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lj
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Re: Spank machine question

Post by lj »

a long time ago I did make a successful machine, rather crude but effective.

I happened to have a 12 volt DC motor designed to provide an under-load speed of 800rpm. I don't recall the under-load current exactly, but around 8 amps. This was mounted with the shaft vertical, and an arm bolted to the pulley block that was part of the original design, the "arm" was used to mount a cane or crop. I set up a couple of Hall Effect sensors which detected a magnet on the arm, so I could "park" the arm at a set position, and the second to switch off the power when the arm had rotated far enough to ensure the target had been hit!

I coded a microprocessor (now you could use an Arduino or similar) to control a magnetic release as well as give a warning of an impending strike, a random number of strikes and a random lock time, as well as firing the motor at full speed and reversing after the strike much more slowly. Actual rotation was about 240 degrees, from rest to target. And just to increase the strike speed and force, I used two 12v lead-acid batteries in series to give 24 volts, at somewhat more current. I would estimate it was running at about 300 watts for the second or so the motor took to go from zero to full speed.

It was certainly very effective, and compared very well with the canings I have received from various Dommes. I think this should indicate the amount of force needed for an effective machine. You can achieve a good result either by lots of power released very quickly, by storing the energy in a spring or elastic system, or applying high power to a rotating motor.
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Donovan
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Re: Spank machine question

Post by Donovan »

Shannon SteelSlave wrote:A wiper motor could possibly work, but it still needs something to load up tension, and release at the correct angle.
Hello,

Indeed, not too bad an idea. Of course, a lot of modification is needed, but the idea is very interesting.
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Re: Spank machine question

Post by kinbaku »

Welcome to BoundAnna, Donovan.
If you search "diy spanking machine" in the search field at the top right, you can get a whole set of information about it on this site.
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Shannon SteelSlave
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Re: Spank machine question

Post by Shannon SteelSlave »

Aloha from Bound Anna, Donovan
Bondage is like a foreign film without subtitles. Only through sharing and practice can we hope to understand.
A Jedi uses bondage for knowledge and defense, never for attack.
I am so smart! I am so smart! S-M-R-T!....I, I mean S-M-A-R-T!
👠👠
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