Making a lensboard

[S.larsson]

I've just procured a Durst 606, It's great apart from the fact that I need a lens board for my secondary enlarger lens. It's a 50mm, 39mm (leica) lens thread and ideally needs an Ixotub. As I've found out the hard way they are very expensive and hard to come by. Does anyone have any recommendations on how to make one?

Regards from Sweden,

Stephan

 

[john_s]

I'm not familiar with the Durst, but an alternative to a threaded board is a slightly larger hole and a 39mm threaded ring (jam nut) instead. If the board is a simple shape maybe it could be cut from sheet stock for (or by) you.

SRB could make one for you but I don't know the likely cost.

Edit: I've just searched for ixotub and it's much more complicated than the flat boards with which I'm familiar (Beseler). It's the difference between Europe and the USA!

 

[John Austin]

Use the WTB classifieds, especially if time is a crucial factor (if you enjoy working with bits of metal ignore this idea)

 

[paul_c5x4]

Does it have to be an Ixotub or will some of the other Durst recessed lens boards fit ?

There is a recessed lens board on ebay at the moment (#290679079821) located in Germany - The seller doesn't give much info, but it might be worth asking what the outside diameter is.

 

[Leigh B]

Hi Stephan,

I strongly recommend using a retaining ring made for the lens in question.

Reason: There are three different M39 "Leica" threads, and they're not inter-matable.

The original was 39mm major diameter but with an English 26tpi 55° Whitworth thread.
You'd need to find a pretty good machine shop to cut that thread, as it's not common.

The other two variants commonly encountered are:
Russian M39x1
Canon M39 x 24tpi 60°

- Leigh

 

[ic-racer]

From what I can tell the more common thread for the Ixotub was 25mm but here is one with a bigger hole than that on ebay with a starting bid of $9.99 : It looks a little odd, maybe it is not threaded and would require a retaining ring as suggested above. http://www.ebay.de:80/itm/ws/eBayISAPI.dll?ViewItem&item=110729151113&clk_rvr_id=321993282832

What would I do? I'd get a common 25mm Ixotub and a 50mm lens with 25mm threads. Those 50mm f4 Componons with 25mm threads should be inexpensive.

 

[Leigh B]

I would expect an original M39 Durst board to have the correct thread.

My comment was addressing the situation where the board had a smaller hole (e.g. 25mm) or none at all,
so the hole would need to be bored and tapped by a machine shop.

- Leigh

 

[S.larsson]

Hi everyone, thanks for all your replies! I've contacted a machine shop to have one made, It'll cost me about €50 under-the-table to make and should fit my specifications exactly. I've left them my lens too so they can make sure the thread fits perfectly. The Lens is a Kowa 2.8/50mm and I'm hoping they will be able to tap that thread out for me.

 

[S.larsson]

To anyone who's interested, I had a lens board made and it works great! I still have the blueprints for it if anyone wants to make their own Ixotub