DURST LATUB help how to remove lens

[charlesalle]

Hello,

I have bought a EL-Nikkor 50mm f/2.8 mounted on a DURST LATUB.
I can't find any information on how to remove the lens from the LATUB.

Does anyone have a guide or hints on how to accomplish this ?

Many thanks

 

[Bob-D659]

EL Nikkors usually have a 39mm male thread and just screw into a mounting plate. Most LATUB's are threaded as well, so just reach in grab the lens and unscrew it counterclockwise if there isn't a retaining ring on the outside of the tub.

 

[charlesalle]

Hi, thank you for your answer.

However, it seems to be difficult to unscrew it, first because I can't hold it right in this small space and second because I fear destroying the aperture ring by unscrewing it.

Here are some pics of the thing.

Thanks again !

 

[Bob-D659]

Can't tell from your first pic if the lens body is flush with the back of the tub or not. Yes they do get tight, the tub is aluminum, so try blasting it with a hot hair dryer for 15-30 seconds to heat it up, that usually helps.

 

[Bob-D659]

Have you removed the inner tub with the two tabs on the front? Pretty sure that screws into the outer tub.

 

[ic-racer]

I have had a lot of success heating lenses to remove stubborn lens rings etc.

 

[charlesalle]

The problem is that I can't find a way to hold the inner tub...
I really don't understand which part holds the lens because the part on the back is much smaller than a M39 thread...

I also tried to unscrew the three small screws but it seems to only hold a small plastic inner plate against the lens.

Is there any exploded view of this available somewhere ?

Here are two other pics, I did my best because I have no macro lens...
Many many thanks for all your help and any additional hints

 

[bdial]

Those screws (and the oblong slot) are part of the lens (just verified on mine). In your picture I can see the mount threads just to the outside of the plate that contains the 3 screws.

 

[Bob-D659]

Well there is more than one size of LATUB, and more likely more than that many configurations. That inner part with two ears extending out the front should turn. Also on some latubs the rear panel with the hole unscrews from the body. It looks like yours was turned down on a lathe as Durst would have never let there be a big shiney surface below a negative. So maybe that panel unscrews from the outer body.

 

[charlesalle]

bdial, thanks, this is a very helpful hint as I didn't know if I had to get the part with the screws off

Bob-D659, thanks for the comments. You are certainly right about the rear panel. It seems as it has been fixed with glue. I am loosing any hope to get this lens off as I tried all your tips.

I wonder if I could saw the cylinder off without harming the lens... will probably try that.

Thanks again

 

[Bob-D659]

I'd drill a couple of holes near the edges of the back panel, across from one another and clamp a couple of bolts in a vice so the ends fit in the holes and use either a strap wrench or a pipe wrench to "unscrew" the outer shell. Or maybe just one hole right at the edge and use a prybar to lever up the back panel if the two holes didn't work.

Edit, you try heating the back panel on the edges with a torch to soften the glue.

 

[charlesalle]

Thanks again for the ideas Bob-D659. I'll try this and when I get access to some sort of dremel or a drill.

The torch option would be the last one as I fear heating the lens too much.

I'll post my results in case someone (although highly unlikely ) is looking to do the same on his Durst plate.

 

[ic-racer]

Looks like that Latub was already buggerd by removing the bottom and gluing on a threaded plate. If you don't have a Durst enlarger and just want the lens, try popping out that glued on piece. Looks like it is just held on with epoxy. Or perhaps saw it off around the perimiter. Once you have the lens and the threaded plate out, you can probably just unscrew them by hand.

 

[charlesalle]

I think you're right ic-racer, that's what came out after all my questions to many professionals.

At first I asked myself how they could have screwed the glued piece without any handle or piece to rotate it.

Like I said, I'll try to burn the epoxy if the drilling doesn't work out.

Thanks for all your help !

 

[charlesalle]

I finally did it

After trying many methods and removing the glue (epoxy, araldit ?) the thing wouldn't disassemble.
So I took a hammer and a screwdriver and gently tapped in the "space" between the silver ring and the black cylinder until I could tear the ripped cylinder off. It was really glued so well that it wouldn't disassemble until I teared the whole parts away.

Here is a pic of the parts.

Many thanks to all of you !

 

[Bob-D659]

Congrats, that was not fun, but at least you now have a useable lens.