Monday 31 August 2015

About Turn!

What are they called & how do they work, please?

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6 comments:

  1. (1)Strap drill.
    (2)Pump drill.
    (3)Two geared hand drills.
    (4)Brace and bit.
    (5)Breast hand drill.
    (6)Large bow drill. This idea was originally used to power fire starters. It was used until quite recently to power watchmakers' lathes. I saw one in use in a watchmaker's workshop just off the Clerkenwell Road in 1978. The craftsman (Dan ? - his surname escapes me) was using the bow in one hand and a cutting tool (used on the forward stroke of the bow) in the other.

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  2. 1. The strap drill was also known as the thong drill until skimpy bloomers made the word unmentionable. 2. I like the 'fly-wheels' on these pump-drills. 3. These also have another name since both hands are occupied with the side handles... 4. Yes, but also?
    5. Yes, do you know the brand of this specific design? 6. Wonderful, about how many turns per stroke would you reckon to get?

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  3. No 5 is a Hotchkiss possibly?

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  4. P.s. How many turns of the stroke would depend on the length of the bow and the bow string, but I would think about 7 or 8 (or so).

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  5. No 4. has a large brass finger nut which allows the teeth of the hand-grip to be disengaged and the handle swiveled in line with the jaws of a combined chuck and adjustable spanner which can be opened,closed or adjusted by the large wing bolt.
    The wrench has sturdy parallel jaws on one side and an arch & toothed jaw on the other. Any ideas about the application for this weird combination tool Rog?

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