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01-30-2018, 08:10 AM   #1
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Arsat 30mm fisheye loose mount

I bought this lens on eBay about a year ago. There has always been a tiny amount of play between the mount section and the lens barrel. Now that play is getting much worse and I can see into the crack between the two sections if I pull them apart. I'm afraid to use it in case the mount and barrel separate entirely and the lens might end up in a river or over a cliff.

It looks like I am probably missing a screw and have a couple of others that are loose that should hold the mount to the barrel. Shouldn't be too hard to fix except that I can't reach the screw heads due to the flange of the mount sticking out. The flange is maybe 1/4" above the screws and makes a parallel plane to the surface that screws go into.
I wonder if I need a special screwdriver or maybe there is a way to remove the mount flange first?

If anyone has any suggestions, I'd love to hear them. The flat rate repair at KEH is about what I paid for the lens so I'm reluctant to put that money into this old thing.

I've Googled around a little and can't find any disassembly info for this lens. Any ideas?


Last edited by mattb123; 04-16-2018 at 09:12 PM.
01-30-2018, 08:37 AM   #2
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Not an owner of this lens, but a quick questions is... loose mount ring or the adapter barrel/spacer?
General suggestion for this is that if the Arsat was adapted for use other than the Kiev or Arsat, then the barrel/spacer is coming loose.
This might mean you will need the ring removed and tighten the spacer screws...maybe a dot of loc-tite as well and then reinstall the mount ring.
Maybe provide a picture of the gap and some folks might chime in with a more precise suggestion?
01-30-2018, 08:54 AM   #3
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QuoteOriginally posted by MysteryOnion Quote
Not an owner of this lens, but a quick questions is... loose mount ring or the adapter barrel/spacer?
General suggestion for this is that if the Arsat was adapted for use other than the Kiev or Arsat, then the barrel/spacer is coming loose.
This might mean you will need the ring removed and tighten the spacer screws...maybe a dot of loc-tite as well and then reinstall the mount ring.
Maybe provide a picture of the gap and some folks might chime in with a more precise suggestion?
Thanks, photos added.

---------- Post added 01-30-18 at 09:14 AM ----------

I just need to figure out how to remove the mount ring and I'll have access to the screws. But the mount ring seems to be very securely attached with no obvious way to remove it.
01-30-2018, 09:33 AM   #4
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QuoteOriginally posted by mattb123 Quote
Thanks, photos added.

---------- Post added 01-30-18 at 09:14 AM ----------

I just need to figure out how to remove the mount ring and I'll have access to the screws. But the mount ring seems to be very securely attached with no obvious way to remove it.
Don't know if this is going to help you much... At least it's possible to ask the guy

?????? - 8 3.5/30 ??????????? ?? ??? ??????????? - NIKONservis

01-30-2018, 12:52 PM   #5
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When you set the lens to the minimum focus and look in and around the barrel... is there a suspicious set screw?
The original Kiev mount was a screw type and if the original lens is simply adapted, the thing may twist off.
However, a set screw is possible to prevent spinning of by accident and if you can't see it outside it may be inside.
The second stage cup portion of lenses that house the aperture levers and such are usually looseness by way of screws hidden under the aperture ring?
In your case, the aperture ring is held in by the rear mount cap and the adapter ring is on top of it.
Again, I'm guessing...thanks for posting the picture.
01-30-2018, 09:53 PM   #6
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No luck on a set screw that I can see. Tried all focus positions, just in case. Aperture ring just moves as much as the missing/loose screws allow.
I wonder if the mount is threaded on and glued or something. No obvious sign of that specifically but it had to come together somehow.
Thanks for the suggestions.
02-04-2018, 04:13 PM   #7
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QuoteOriginally posted by mattb123 Quote
I bought this lens on eBay about a year ago. There has always been a tiny amount of play between the mount section and the lens barrel. Now that play is getting much worse and I can see into the crack between the two sections if I pull them apart. I'm afraid to use it in case the mount and barrel separate entirely and the lens might end up in a river or over a cliff.

It looks like I am probably missing a screw and have a couple of others that are loose that should hold the mount to the barrel. Shouldn't be too hard to fix except that I can't reach the screw heads due to the flange of the mount sticking out. The flange is maybe 1/4" above the screws and makes a parallel plane to the surface that screws go into.
I wonder if I need a special screwdriver or maybe there is a way to remove the mount flange first?

If anyone has any suggestions, I'd love to hear them. The flat rate repair at KEH is about what I paid for the lens so I'm reluctant to put that money into this old thing.

I've Googled around a little and can't find any disassembly info for this lens. Any ideas?
-------------------------------------

Here are three photos of my Arsat 30mm for sake of comparison. The place you show in red appears to be the place where my lens mount has a set screw, apparently to hold the circular part (the part that contains the flanges) in position, both vertically and around the circumference of the mount. Your screws that are beneath the flanges appear to be out of place compared to the position of the screws on my mount. Perhaps that is because your set screw is missing, and this has allowed the flange part to spin away from its proper position to a position covering the screws.

My mount is secure and shows no movement or gap.

Trusting that this information may be of value to you.

Added note: Position of the set screw on my lens. Place the lens in front of you, with the mount facing away from you. Turn the aperature ring fully to the right so that the working aperature is f 3.5. The set screw will be directly above the 3.5 aperature inscription
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Last edited by ivanvernon; 02-04-2018 at 04:21 PM. Reason: Added note on set screw position.
02-04-2018, 09:55 PM   #8
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QuoteOriginally posted by ivanvernon Quote
-------------------------------------

Here are three photos of my Arsat 30mm for sake of comparison. The place you show in red appears to be the place where my lens mount has a set screw, apparently to hold the circular part (the part that contains the flanges) in position, both vertically and around the circumference of the mount. Your screws that are beneath the flanges appear to be out of place compared to the position of the screws on my mount. Perhaps that is because your set screw is missing, and this has allowed the flange part to spin away from its proper position to a position covering the screws.

My mount is secure and shows no movement or gap.

Trusting that this information may be of value to you.

Added note: Position of the set screw on my lens. Place the lens in front of you, with the mount facing away from you. Turn the aperature ring fully to the right so that the working aperature is f 3.5. The set screw will be directly above the 3.5 aperature inscription
Thanks! That does help. I think my red dot might have a set screw under it. It looks like it is nail polish or something like that. I'll see if I can get to it and report back.

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