HELP!!! MY Grandagon 90/4.5 stuck on the shutter!!!

[WilliamXP]

I just got my 'NEW' 2nd-hand Grandagon today, which is being mounted on a Sinar board. Fair enough. So I screw the front cell off the shutter. Simple. And then, when I do the rear cell, I felt some resistance come and go about three times and then it stuck there. So I use more force to screw this thing off. And there the rear cell goes off without its screw ring!!!!

The ring is STILL stuck on the shutte!!!





NOW NOW HOW COULD I GET THIS THING OFF!! AND MOUNT ON MY SPEED GRAPHIC!!?????

I THOUGHT RODENSTOCK COULD DO BETTER THAN THIS!!!

ANY COMMENTS WILL BE WELCOME. i AM NEW TO HERE AND NEW TO LF AS WELL. :P

MANY THANKS
YING

[E. von Hoegh]

Jesus, that doesn't sound good. Worst case, the (aluminium) threads galled and cold welded themselves together. Put some penetrant on, a tiny dot with a toothpick every 120 degrees and try gently to move the threads.

It isn't Rodenstock's fault.

[Andrew]

I'm not familiar with this rig but it looks like there's a locking ring still in place.... what happens when you take it off?

[WilliamXP]

Jesus, that doesn't sound good. Worst case, the (aluminium) threads galled and cold welded themselves together. Put some penetrant on, a tiny dot with a toothpick every 120 degrees and try gently to move the threads.

It isn't Rodenstock's fault.

Thx, E.

Frankly, I dont have any tools. I really mean it. I don't even could find a proper screw driver... Anyrate, what kind of penetrant we are talking about??? I don't even see any gaps anywhere to begin with.... thats why I post for help...

I know its not R's fault. It very well being bended (remember I mention the resistances when I screw it off) in the thread that causing this...

I just being a bit frustrated as this lens is my OWN 3rd LF lens (but I used LF in uni for sometime). And how much hope I put into this lens, I even planning a holliday trip at the end of the month to play with it... *sign* life is truely full of the unexpected...

[WilliamXP]

I'm not familiar with this rig but it looks like there's a locking ring still in place.... what happens when you take it off?

I don't think it have any locks or anything like it around the lens. It seems just a smooth and simple piece of metal and glasses to me. I mean it should be just screw out the rear cell and then the retaining ring. The shutter should say 'Good Bye' to the lensboard then... That is what I expected...

[JimL]

I think Sinar uses some thread locking compound when they mount the lens cells. You could try putting some drops of acetone around the join between the Sinar part and the Rodenstock part. Also drip some in through the front side.

[Andrew]

this ring
it looks like a shutter locking ring/ mounting ring/ retaining ring/ other names also used
but you'd need a spanner wrench to get it off cleanly
[sometimes you can unscrew the shutter at the front and do it that way]
I assume that once it's off the shutter etc will come away and you'll be able to get better access to the rear lens cell components that stuck
and if not, you'd still be able to get the thing onto a new board
????????????

[E. von Hoegh]

this ring
it looks like a shutter locking ring/ mounting ring/ retaining ring/ other names also used
but you'd need a spanner wrench to get it off cleanly
[sometimes you can unscrew the shutter at the front and do it that way]
I assume that once it's off the shutter etc will come away and you'll be able to get better access to the rear lens cell components that stuck
and if not, you'd still be able to get the thing onto a new board
????????????

He has to remove an adapter ring which is there to adapt the cell threads to the shutter threads FIRST.
For penetrant, Liquid Wrench, Kroil, No. 2 heating oil, etc.

[WilliamXP]

He has to remove an adapter ring which is there to adapt the cell threads to the shutter threads FIRST.
For penetrant, Liquid Wrench, Kroil, No. 2 heating oil, etc.

Great News! The seller agreed to return the lens. Great!

I also do think the penetrant is a good idea. But instead of heating, would cooling be better for this task? Just wandering...

[E. von Hoegh]

Gentle warming will get the penetrant in there faster. Probably best to return it, though. I failed to notice the part about it being bent.