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    Re: Dennert & Pape MHR-1 Dennert & Pape MHR-1 HR-2 Cylindrical Slide LineRuler
    From: Brad Morris
    Date: 2013 Jan 27, 18:16 -0500

    Hi Wolfgang

    20 grooves around on mine.  The grooves have sharp corners, not rounded. 

    I measured, using a linear scale,just shy of 13/64 of an inch.  13/64 *25.4= 5.159 mm.  Since its shy of 13/64, 5mm is probably right. 

    There are also 20 bars, at the same dimension.  Thus we have 40 units of 5mm or 200mm circumference.  This yields a diameter of 63.662 mm. 

    The step size is 3/64 of an inch (1.19 mm).  Again, these are square steps

    Best Regards
    Brad Morris

    On Jan 27, 2013 3:16 PM, "Wolfgang Hasper" <wolfgang.hasper{at}web.de> wrote:

    Marc,
    thanks for your message and the kind invitation.
    I am, however, sufficiently familiar with the use of
    the instrument. I will need more practice to increase
    speed, but as my reproduction is now complete and neat
    I am looking forward to gaining routine soon :o)
    
    I would be interested to stay in touch anyway and to
    discuss experience!
    What is your impression of the practical use at sea?
    
    I have prepared forms for the calculations, following
    the MHR1 nomenclature and including the
    almanac-related and sextant correction calculations.
    They are good for five sights in one A3 sheet and come
    along with a plotting sheet. If you are interested I
    will be happy to send you a pdf?
    
    I do lack one detail for my second attempt on the
    reproduction:
    This time I want to have actual machined grooves on the
    base and no work-around. Could you tell me how many
    groves there are? My best estimate is 18 groves of 5mm
    width each...
    
    Thanks again for your message, I am really happy to
    learn there is one more user of such instrument so
    relatively close to myself :o)
    
    Best regards
    
    Wolfgang
    
    
    
    
    Am Sonntag, 20. Januar 2013 20:08 schrieb Marc Giordan:
    > Sir,
    > I am French and also quite familiar with the use of
    > the MHR 1 at sea (I used it for 2 atlantic crossings
    > by sail) Would any one wish to be trained in using
    > it, I am ready to help ! The MHR 1 was bought by my
    > father some 30 years ago at the flee market in Paris
    > Yours
    > Marc Giordan
    > 26 rue de Paris
    > 78560 le Port Marly
    > (0033)675210703
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    > View and reply to this message:
    > http://fer3.com/arc/m2.aspx?i=122013
    
    
    
    

    View and reply to this message: http://fer3.com/arc/m2.aspx?i=122135

       
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