# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Message:αβγ
Message:abc
 Add Images & Files Posting Code: Name: Email:
Re: Dennert & Pape MHR-1 Dennert & Pape MHR-1 HR-2 Cylindrical Slide LineRuler
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

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
> ----------------------------------------------------
>------------ NavList message boards and member
> settings: www.fer3.com/NavList Members may
> optionally receive posts by email. To cancel email
> delivery, send a message to NoMail[at]fer3.com
> ----------------------------------------------------
>------------
>
>
>
>
> 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

Browse Files

Drop Files

### Join NavList

 Name: (please, no nicknames or handles) Email:
 Do you want to receive all group messages by email? Yes No
You can also join by posting. Your first on-topic post automatically makes you a member.

### Posting Code

Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
 Email:

### Email Settings

 Posting Code:

### Custom Index

 Subject: Author: Start date: (yyyymm dd) End date: (yyyymm dd)