What is it? Set 319

[Cydrome Leader]

just touch the brass colored part when one is running under water.

it's not hot but it's surprisingly painful, and I wonder why that is.

[Lloyd E. Sponenburgh]

Cydrome Leader fired this volley in news:hiqesi $ots$ [e-mail]:

Ultrasonic energy will heat the tissues, even though the transducer itself is not hot. Moving molecules are hotter when moving faster, cooler when slower. If your finger tip's molecules are agitated into faster motion, they get hot.

LLoyd

[Lloyd E. Sponenburgh]

"Lloyd E. Sponenburgh" fired this volley in news:Xns9D019AF3D909Clloydspmindspringcom@216.168.3.70:

I might add that the energy also causes gas bubbles to form inside the pores of your skin, and the expansion of those bubbles causes something akin to a superficial case of the bends in your skin.

LLoyd

[DoN. Nichols]

For something all of 1-1/2" diameter? It would barely work between thumb and index finger.

It works only in the vicinity of the diaphragm which is down in the hole. Typically, it would be sunk about a half inch to an inch below the top of the water surface, and it generates a cloud of water droplets as a fine mist above the surface of the water. I think that we can declare the minimum working level for this as just below the crossbar of what you call a handle, and I call a sensor.

There is something like this (though without the individual head shown here) in the ultrasonic humidifier which I have had for many years now. That one has a floating donut magnet around a shaft which includes a mercury wetted reed relay cell, so when the water gets below the proper level, it turns off to protect the ultrasonic generator. The water, in the case of my humidifier, is supplied from a tank with a demand system so it only gets more water when the water level falls below a preset level.

That hole would be the mounting ring for the piezoelectric diaphragm which produces the ultrasonic energy.

Enjoy, DoN.

[DoN. Nichols]

O.K. That works.

Is the groove just beyond the pressure plate for the adjustment leadscrews a slit all the way to the bottom, or is it just a reference line?

It could perhaps be placed on a workpiece and adjusted so the groove lines up with some feature to measure the precise angle at which the feature is located.

Are the knobs large enough to allow handling it's weight?

Or for verifying that something was made to the proper degree of precision.

Perhaps you need to find someone who worked for the lab which specified it?

Enjoy, DoN.

[Rob H.]

Below is the best view of the other side that I have:

don't think the arrow points to anything, an image search of 'cranequin' shows that some of these devices have similar arrows but others don't:

the arrow was used to hang the device on their belt.

Rob

[Cydrome Leader]

That might be it. It didn't feel like a normal burn, and was pretty fast acting, like an electric shock, but continued to hurt for a bit afterwards.

If anybody gets bored try it out some time.

[Steve W.]

It would have been used to hang the crossbow the cranquin was attached to from the bow mans gear using a rope or leather trace. Sort of an early sling. The rawhide part is not a universal fit item. It would have been soaked in water, then slid over the butt of the bow until it reached the spot just behind the grip. Then it would be allowed to dry. This held it securely in place and provided the anchor point for the cranquin to operate against as it drew the bowstring. Consider that the common cross bows of the day had between 600 and 800 pounds of draw and you see the need for a LOT of mechanical advantage to draw the bow.

[Rob H.]

Thanks, that makes sense. I was hoping to find a youtube video of someone using a winder but didn't have any luck.

Rob

[Steve W.]

They are not hard to use. Most had a release that let the rail loose. Then you hooked the T bar over the string. Engage the crank and wind the string back until it drops into the dogs on the lock. Back the crank off one turn to release the string, drop in the bolt and your ready to go.

[DoN. Nichols]

clip to hold the crank carriage in the upper-most position -- or a clue that you now have the string far enough back so you can now hook it on the catch of the crossbow.

> Maybe the arrow was used to hang the device on their belt.

Perhaps so.

Enjoy, DoN.

[Northe]

Rob,

Take a look here:

The video shows a number of devices for setting the bow string.

Northe

[Rob H.]

Thanks! That's an interesting video.

Rob