Inside a hand grip strength tester - dynamometer.

This is a device that tests your grip strength and logs the peak reading in either pounds of kilograms. It's used in the fitness and medical industries.
The construction is actually better than I was expecting. Very robust.

The keywords for an eBay search are digital hand dynamometer.

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[tinplategeek]

Clive - "I have a strong grip" - sounds like much misspent teenage years to me.

[robertsmiczsmiczamplificat]

I use one all the time at my MS center. I have MS and they keep track of my strength. It gives them a heads up on a MS flare up.

[noisytim]

No way you’re 54! You look way way younger...

[Uncle-Duncan-Shack]

I am average at using the crimper for insulated lugs, but I have a colleague who makes corkscrews out of six inch nails with bare hands.
He would love to play with that.

[Smegheid]

Funny you mention baggage scales; the same company also makes those.

[twocvbloke]

It's quite amazing how strain gauges work, so little movement, but able to record that much tension applied to the metal bar... :)

[Cloudy.]

Clive's 54? Damn, I would've guessed he was at least 10 years younger.

[MD]

"Useful, let's take it to bits" - 2019 Clive :)

[HR-ucbz]

I had something similar in the hospital. I was very weak and the dietician used something like this to test my strength. It wasn't electronic. It had like a tyre pressure type gauge on it. It was quite fun to use

[Cryss]

61kg?! Last time i used this in high school i was so happy for my 32kg on right hand and 29kg on left hand...

[merlinathrawes]

Love that circuit board at 8:49. Flipped over and showing the IC's, it looks like a steampunk/retro robot head with the wires coming out the sides as antennae. Splendid!

[LostBeetle]

I'm getting one, I fractured my right hand and needed pins. When the cast came off it was hand therapy, and at the end of five weeks of hand therapy I managed 66lbs with my right hand (the one that was broken), and 135lbs with my left. I wonder what my right was before the fracture happened. Thanks for the review, I just ordered it and now it just needs to ship.

[PushyPawn]

Ever since my relationship ended, my grip strength has gone through the roof.
A shame it only improved on one hand.

[RocRizzo]

Congratulations Clive, in getting your first 1/2 million subscribers!

[ManWithBeard]

Interesting thing about strain gauges by the way: typically you would want to set them up in a Wheatstone bridge kind of arrangement as you said, but there are several ways of going about it. The best way is to have two opposing gauges parallel to the direction of elongation, and two perpendicular. So two of them have a resistance increase and two have a resistance decrease as the thing deforms, yielding the largest voltage difference in the bridge. However, you also have half-bridges where miniaturization is important, comparable to a simple voltage divider, and up to all but one of the strain gauges could be replaced by a dummy or a matching resistor, to save cost. If you were to remove that white silastic you'd likely see this bridge arrangement split over both sides. I'm actually kind of surprised by how it's constructed. If it was me I'd have molded in a somewhat sharper point for both ends of the aluminium bar to rest on so you wouldn't have to worry about nonlinearities as the plastic deforms. But I guess they tested it and decided it was good enough for what it's for.

[LiamB]

Wow, I've just noticed you're nearly at half a mil subs. Congratulations Clive, you big strong bear!

[clusterfork]

I like when you read out the full titles of eBay listings. I do that too, usually in a voice that pretends it isn't just keyword spam.

[rusty-]

Should have load tested it on the Vice of Knowledge to see how far it goes before it breaks :)

[JerryEricsson]

Back in '93 I was seriously injured in an accident. Since it was in the line of duty, Workers Comp kicked in and decided to test me to see if I was telling the truth, well me and the surgeon who operated on me to correct the damage, so they sent me through a series of "functional capacity" tests. The grip test was one of the many tests they had me perform over the 2 day process. Back then they used a rather large chrome plated device that weighed in at about six pounds and had a dial meter on it with a stop needle that would freeze at the strongest point. The tests were designed, not only to test your physical strength and ability but were set up with a sort of double purpose to insure you were not holding back, since holding back on one test might show in another test down the line. Being an honest person, and not trying to fake an injury following the three major surgeries it took to get me walking again, I passed the tests, and Workers Comp was happy for a month or to before the began another round of their pscyh warfare against the worker. In the end, a wonderful lawyer and understanding judge awarded me the 100% disability that all the tests indicated I should have. Oh add in another 2 years where the bureau sent me to college to be retrained from a police officer to a paralegal, and while I passed the course with a 4.0 GPA, I could not buy a job because of my disability and advanced age (I was near police retirement age at the time of the accident.

[nicolek]

Thank you for the Kg conversion. I may be old, but I work in metric.