Saturday, January 10, 2015


Today I called Oneway about a lathe that was making a louder than expected noise during operation, and after being run for a short time would not restart without waiting to cool.

I suspected that the problem was in the DC motor, but it is almost a new lathe and should not have problems there. So I spent about 30 minutes on the phone with their technician, and ended up taking the motor off to check the wiring. I found one small wire to be disconnected and loose within the junction box at the rear of the motor.

That loose wire was making the 3 phase motor work as single phase. So it ran, but grumbled loudly, and would overheat the sensors in the control box. With that loose wire reconnected, the lathe works in almost perfect quiet. The great thing is that by fixing it myself, and the fix being so simple, I'll not be waiting for parts to arrive, and the lathe will be working for next week's classes.

dexterous, dexterity... c.1600, "convenient, suitable," formed in English from Latin dexter (see dexterity) + -ous. Meaning "skillful, clever" is from 1620s. Sloyd or slöjd has the same meaning, skilled or clever.

The term dextrous or dexterity comes up because Barbara, who is translating the book by Christian Jacobsen has come across the word håndgrep and has wondered about the exact meaning intended by Jacobsen. That sends me back to Frank Wilson's book about the hand which mentions Napier and his study of the various grips.

According to Napier, hand movements are either prehensile or non-prehensile. What I am doing at this moment with my fingertips on the keyboard, poking letters into the electronic keyboard would be called a non-prehensile movement because it does not involve a grip. As you slide your fingers over the iPad resting in your lap, that also would be non-prehensile. On the other hand, if you were to hold the iPad in one hand and slide a finger on the other,  your hands would be involved in both prehensile and non-prehensile movements, respectively. Napier concerned his important  work The Prehensile Movements of the Human Hand with the study of the movements of the hand that required a grip. So, In antiquarian Danish or Norwegian, his paper could have been called Håndgrep.

Two different grips aare shown in the images above. The upper image Napier would have called a "power grip." The one below might have been called a "precision" grip or a modified pencil grip.

It may be enough for some that their hands be used in no better way than to slide fingers over glass. To do so on an electronic tablet can give an illusion of mastery, as you work with skills already fixed in place within the device. For those who think that real hand skills that exist within the student or within ourselves and our own experience are no longer needed, I suggest, "Get a grip." A håndgrep will do.

Make, fix and create...

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