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-   -   Threaded 82mm ring adaptor (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/136091-threaded-82mm-ring-adaptor.html)

Stuart Campbell October 15th, 2008 05:24 AM

Threaded 82mm ring adaptor
 
The hd200 got struck by a tank last week (full shooting report to follow) and in doing so whacked the matte box thus threading an 82mm adaptor ring into the lens. It's as stuck as stuck can be.

Anyone know if you can remove the sun shade which holds the 82mm thread at the end of the stock lens so I can be a bit more aggressive in getting it off? Obviously any pressure exerted against the threaded ring acts against the lens as a whole and I don't want to do that.

My last resort is to carefully hack saw the top of the ring in the hope that that would release the tension enough and allow me to break it off.

We have a job which requires screwing a different adaptor into the lens and we can't do that until we get this wretched adaptor ring out!

by the way...the camera survived!

Paul R Johnson October 15th, 2008 05:40 AM

I had almost an identical thing happen to me (well, not with a tank). I drilled a 3mm hole through the flange top and bottom, 180 degrees apart. Then I put a rod through from top to bottom. This gave me the pressure I needed, spread evenly so the ring doesn't distort and jam. A quick heave and it came unstuck quite easily with no damage. A little black sharpie colouring in left the ring quite usable and without the usual grooves, cuts or pliar rings.

Stuart Campbell October 15th, 2008 05:47 AM

Hi Paul,

So, you ended up with a rod running across the face of the lens? Do I understand that right? I'll have to see if there's room to drill in that direction but the adaptor ring is pretty much all the way in so I doubt it.

How did you support your lens when twisting by the way?

Stuart

Paul R Johnson October 15th, 2008 07:18 AM

just gripped the front element in one hand, finger and thumbs on the rod where it emerges - kind of gives you enough grip - same idea as the old peoples jar openers. On my ring, when screwed in there was easily enough to drill through. If yours doesn't protrude enough, how about doing your hacksaw cut at both opposite edges, then putting the hacksaw blade, teeth edge down, into the jaws of a workmate, lowering the camera towards it so the slots engage, then turning the camera? You get the leverage you need. As soon as the jam clears it will unscrew easily, I hope?

Stuart Campbell October 15th, 2008 02:12 PM

Paul, the problem I'd have with such a method is that the resistance when turning would come from the lens mount on the camera body before any force acted upon the stuck ring itself. This ring is in so tight I'd be worried about stressing or distorting the bayonet fitting on the camera body or some part of the lens body itself.

It's for this reason that I'm trying to figure out if there is a way to remove the sun hood from the end of the lens first as then I can go mad trying to get the ring out without worrying about the camera body or lens.

When I say sun hood I mean the last part of the lens in which the stepped focal ring turns into (that make sense)? I seem to think I've heard of this being removed before but maybe I'm imagining it!?

Once I've got this off I'll have a go at your suggestion and drill through across the face of the ring.

Cheers.

William Hohauser October 15th, 2008 02:41 PM

This is a real problem even if a tank wasn't helping out.

This solution probably would work but it's worth a try. Get a cooler gel pack or a sealed ice pack and hold it to the ring without touching the rest of the lens. Keep it there for about 5 minutes and then try to move the ring. If you are lucky the ring will have shrunk enough to move. This works well for filters or rings that have sand jammed into the threads when screwed onto the lens.

Kennedy Maxwell October 15th, 2008 02:42 PM

Maybe you could try chilling the ring a bit, or a drop of penetrating oil to the threads through the gap between the ring and lens barrel. Also you could use a jar lid remover available in the kitchen utensil section of a department store (Walmart, Target, Sears).
Good luck,
Ken

Stuart Campbell October 16th, 2008 01:18 AM

All great ideas guys but I'm reluctant to try any more forcing until I can get the sun hood which the ring screws into away from the lens itself. I've obviously got the lens off the body now but any twisting forces are transferred through the lens body and I want to avoid this.

Cheers

Werner Wesp October 16th, 2008 10:37 AM

Is this the 16x5.5? I can tell from experience that one can't have too much pressure whatsover. Good time to get another lens :-)

Stuart Campbell October 16th, 2008 10:47 AM

Thanks Werner but buying a new lens that only fits this camera just doesn't make economical sense! I'd rather just get the threaded adaptor off.

Anyone out there know if the adaptor thread holder / sun hood is designed to come off before I start hacking at it?

George Strother October 16th, 2008 11:42 AM

I've removed stuck filters or adaptors from camera lenses several times using two rubber strap wrenches. They are inexpensive and available from most tool sources (Sears, Home Depot, etc).

For me, the first step would be to remove the lens from the camera body.

Then a strap wrench around the adapter ring and one around the lens as close to the adapter as possible. No marks, cuts or scratches. The trick will be to keep the strap wrench on the adapter ring when you start turning.

Stuart Nimmo October 18th, 2008 04:56 AM

Yes the lens hood usually comes off the standard lens Stuart. Looking at the front of the lens, push the lens hood in slightly and twist it anticlockwise. You then slide it towards you and off. It is a tight fit and the problem may well be that it won't slide off with a filter still attached.

One other Idea maybe (and you are right, take the lens off the camera first) I would gently try using a good, reversible, variable speed electric drill with a rubber sanding disk (no sand paper!) cut to about 85mm,carefully protect the front lens element with a piece of sheepskin (buffing pad?) and place the exposed edge of the rubber disk against the outer face of the stuck ring. Hold, push against the ring prey and having made very sure the drill is turning in the right direction, just give it a very short squirt. The friction and jerk should do the job.

The second idea is to ask to see the tank drivers insurance cover!

Good luck Stuart

Stuart

Stuart Campbell October 19th, 2008 12:18 PM

That's great Stuart. I'll give that a try as soon as I get into the office in the morning and let you know!

Stuart

Jack Walker October 19th, 2008 01:28 PM

Try a filter wrench:
General Brand | Filter Wrench (Set of 2) | B&H Photo Video

Stuart Campbell October 19th, 2008 02:21 PM

Jack that looks like a very useful tool.

Shame I need to get this filter off very quickly now otherwise I'd give one of those a go.


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