I randomly ran across this in a photo on FetLife some time a couple of weeks ago and impulse purchased one, they’re available from https://spankermachine.com.

This post will cover a first impression and some basic testing that I’ve done so far.

Out of the box there are some disappointments, the mounting hardware is definitely NOT stainless steel as claimed on their website. The upright is clearly a die-cast zinc alloy (much of the gravity of the package comes from this part), the arm is zinc plated steel, and the bracket is cast aluminium. Nothing actually *wrong* with those material choices, but I object to them claiming otherwise. The deathdapter it came with was wrong, it had a US plug on it not an Australian plug, not really a big deal because I’ll probably just replace the whole power supply in any case. The power adapter itself is a little chintzy, feels flimsy on the outside, the internals look OK-ish but I’ve not done a megger test on it yet. The main body of the machine is all plastic.

The design is rock simple, basically you have a torsion spring wound in the top section which the “actuator” is attached to, in the bottom there is a gearmotor which drives a dog which engages with the actuator end of the spring to draw it back, the “power” control, basically adjusts a slot which causes the actuator end of the spring to slip down over the tip of the dog releasing the spring tension and driving the actuator forwards.

It seems that the “new” version (website indicates that the “new version is 30% more powerful”), may be of a different design to the one featured in the  SPKM-MAK-3 video on their website (presumably the “original”). From what I can tell from the video it looks like the original actively drove the actuator, because after each stroke it seems to “hunt” for it’s zero (this is visible by the slow motion forward movement after each stroke prior to drawing back for the next), I may be wrong though as I’ve not taken video of the unit I have so I can’t tell for sure that it’s not just an artifact in the video.

The upshots of the rock simple design are; it’s unlikely to have a mechanical failure (unless you break the spring, though there might also be some risk of “wearing out” the power control), and that makes it an awesome candidate for modifications. More on that later.

Given its size it’s pretty punchy, not quite what I was hoping for (I was really looking for something that could deliver on “six of the best” with a cane), but with the right choice of implement and orientation it does the job pretty effectively.

Paddles and such seem work best with the actuator arm operating in a horizontal plane (machine upright or upside down), canes and similar seem to work best with the arm operating vertically, (i.e. such that the cane is coming downwards). To my surprise the most “punchy” implements I tried with it were a ~4mm plastic coated fibreglass garden stake type thing which I think was bought from Daiso, a stock standard 30cm wooden ruler (the hole in the end of the wooden ruler for hanging it adds significant extra effect) and a riding crop. In a nutshell, if you want a severe session, plan to go long rather than hard.

The mounting is not as solid as I’d like, but given the objectives of the device manufacturer that’s not terribly surprising. This will also be something I will be looking at improving (and adding some features around) in the future (pile of parts en route from Banggood currently).

The good

• Decently punchy for its size (even if it’s not quite as punchy as I’d like).
• Amusing packaging, they’ve really gone to town on making it look like something other than what it is, right down to the nameplate on the bottom of the main unit.
• Excellent hackability.
• Simple design should hopefully lend good longevity.
• At first blush the “actuator” appears to be some kind of glass reinforced nylon so will hopefully hold up well.
• The octagonal mounting system is a novel way to get angle adjustment.

The bad

• Mounting hardware is not as claimed, and is a bit sloppy in general which will be causing some loss of energy from the “business end”.
• It’s quite noisy, but with any sort of impact toy some level of noise is unavoidable so I suppose that’s not a big deal.
• Potential wear point on the “power control”. Remains to be seen how much of an issue that will be.
• The timer is a cute idea but IMO not terribly useful (also quite noisy), if it weren’t clockwork so it only operated when the power was on it would be more useful, my first mod will likely be adding a bypass switch.
• The price is a bit iffy, I can understand why it is where it is (because tools for plastic injection molding are REALLY expensive), but for what you get it feels a bit high.

Conclusion

Does the job pretty well, though you need to be a bit careful with your choice of implement. A little on the expensive side. I’d provisionally recommend it so long as you’re not looking for heavy hitting. I may buy a second unit in future so I can use them “in stereo”, though then I’ll have to start buying duplicates of all my implements…