Leather Covering & Prism on Finderscope.

[marcopolo]

Hi all,

The 1930's scope i'm doing the refurb on i'm trying to keep as much original as possible. The finderscope needs a bit of TLC so Iv'e got a couple of q's and a bit of advice needed as i've never disassembled a prism assembly before.

1. The barrel has a leather covering over it and the leather is unsavable. Does anyone know a UK fabricator, even better in Scotland, that will make me a new leather sleeve? Synthetic or real.

2. Looking down through the 50mm objective it is clear the prism is corroded/damaged. Has anyone got a good web link to a way or replacing the prism or refurbing a finderscope. It is of course a RA finder.?

Finderscope pics here:

 

[DaveL59]

depending on the length of the finder body there's a few options using self-adhesive camera body leatherette, for example (one I've been considering for a lens I have):

Camera Body Replacement Leatherette self-adhesive Black & Red Snake | eBay

It generally isn't very thick which may/not be advantageous and it also may help to apply some contact adhesive at the edges to keep them well stuck down. You can of course find other colours, black, navy etc. There's similar available via Amazon too. In theory you could perhaps use thin leather and hand stitch it tho you'd also need a comb punch to make the rows of holes to thread through as it'll be almost impossible to push a needle in reliably without:

Leather Craft Tool 1/2/4/6 Prong Lacing Stitching Punch Hole (4mm) : Amazon.co.uk: Home & Kitchen

Failing these, perhaps talk to someone in the motoring side who refurbishes steering wheels as they are often leather clad and hand sewn. They will likely want the finder body so they can custom fit to it. No clue how much that'd cost but you'd end up with a nice professional finish, just send it minus the optics to avoid damage.

 

For the finder are you able to remove the RA part and open it up to access the prism? Might be the casing has corroded but if lucky the prism may be ok after a clean. You'd need to measure up the prism and source a suitable replacement or perhaps strip out a prism from a modern diagonal like the Celestron one if it is a suitable size, which would likely give the bonus of it being coated.

hope that helps

[marcopolo]

That does help, Thankyou. Much appreciated. I’ll report back after I’ve found a solution(s), kind regards.

[AstroKeith]

You might be surprised by how leather restores with the right treatment. (Have you watched the Repair Shop?)

That doesnt look to bad in the photos

Are you able to disassemble the finder? It looks like a one off modification of a terrestrial hand held telescope so difficult to give advice.. The square prism holder needs getting into! 

[marcopolo]

Hi Keith, unfortunately on the side you can't see in the picture there are bad rips......

On taking it apart it has a pentagonal prism  on which the coatings were quite badly damaged, I managed to find and order this:

https://www.aliexpress.com/item/4000937851400.html

The one in the scope is 28mm. This one is 25mm. There might be slight vinetting but that's fine.

Also I found this for the leather after Dave's advice (thankyou).

 

https://www.ebay.co.uk/itm/221994857297?_trkparms=amclksrc%3DITM%26aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3D2165177d3d2b49f0a027b2537e38873b%26pid%3D100675%26rk%3D1%26rkt%3D15%26sd%3D221994857297%26itm%3D221994857297%26pmt%3D0%26noa%3D1%26pg%3D2380057&_trksid=p2380057.c100675.m4236&_trkparms=pageci%3A681b96ac-1bcc-11ed-a8b1-aa28687f22ec|parentrq%3A9c52725a1820ad3929ca6227fff9ea80|iid%3A1