Welded filter thread

Sandy Hancock · 03-17-2012, 06:57 PM

Brand new Heliopan circular polariser on a nearly new Sigma EX 17-50.
I just can *not* get the thing off. It's been a week now :-(
Part of the problem is of course difficulty getting purchase on the thin rim that threads into the lens. Strength is not the issue. I have tried carefully applying a penetrating lubricant to no avail.
Any suggestions??

**Ex Finn.** · 03-17-2012, 07:02 PM

Rubber band around the filter or wearing rubber gloves might help with traction.

pezmaker · 03-17-2012, 07:11 PM

I had this problem with a polarizer and a close focus lens filter locked together. If Ex Finn.'s trick doesn't work (or if you don't have those components), toss the offenders in the freezer for a while, it should shrink the bits enough to easily pull apart. Again, just my experience ONE time... No matter *what* I tried, I couldn't get them apart. I put them in the freezer and it was as if they were never locked together.

**jpzk** · 03-17-2012, 07:16 PM

I did something similar as pezmaker ...

I put an ice cube tray on the kitchen table, covered it with a thin cloth and put the lens with it's filter side directly on the cloth ... left it there for 5 minutes (or longer ?) andthe filter could be unscrewed with no effort at all.

This was suggested by a PF member here.

JP

Docrwm · 03-17-2012, 07:16 PM

If you can't get enough of a grip with the rubber band, try one of those rubber sheets that they sell to help with opening bottles - they are more forgiving. Also, the temperature trick works but be careful with the lens - personally, I'd try the fridge first.

pezmaker · 03-17-2012, 07:18 PM

Fair point. This was just a "macro" filter and a polarizer, I don't know if I'd been so quick to throw a lens in the freezer. Well, at least a new one. My M 1.7 or helios 44-2, wouldn't hesitate, but who knows with these new fangled auto focus lenses

Sandy Hancock · 03-17-2012, 07:22 PM

I'll try the rubber band, but I really like the cooling idea.
I'll give it a go as soon as I get home. Thanks

Docrwm · 03-17-2012, 07:29 PM - **1 Like**

Originally posted by pezmaker

Fair point. This was just a "macro" filter and a polarizer, I don't know if I'd been so quick to throw a lens in the freezer. Well, at least a new one. My M 1.7 or helios 44-2, wouldn't hesitate, but who knows with these new fangled auto focus lenses

Electronics can be finicky that way.

**jatrax** · 03-17-2012, 07:42 PM

Another thing to keep in mind is that strength is not your friend here. The tighter you grip the more distorted the threads get and thus bind. Use the least amount of force you can, rubber band or rubber sheet helps to get purchase without gripping tightly. Avoid squeezing from the sides if you can, instead put the rubber sheet on top and gently try to twist it.

Docrwm · 03-17-2012, 07:46 PM

Originally posted by jatrax

Another thing to keep in mind is that strength is not your friend here. The tighter you grip the more distorted the threads get and thus bind. Use the least amount of force you can, rubber band or rubber sheet helps to get purchase without gripping tightly. Avoid squeezing from the sides if you can, instead put the rubber sheet on top and gently try to twist it.

Excellent points!

**monochrome** · 03-17-2012, 07:48 PM

I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter.

Docrwm · 03-17-2012, 07:52 PM

Originally posted by monochrome

I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter.

You might think about adding that one to this thread:
https://www.pentaxforums.com/forums/pentax-camera-field-accessories/171466-wh...lped-most.html

Philoslothical · 03-17-2012, 07:53 PM

Lenses get a lot colder than the freezer during normal winter use outdoors. I wouldn't worry much about the cold, but condensation could be an issue if it's humid in the house. Putting the lens in a plastic bag before freezing it would help mitigate this. The plastic bag might even help to grab the filter when it's taken out.

RioRico · 03-17-2012, 08:12 PM

Originally posted by monochrome

I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter.

That trick works fine with a fixed filter, not so fine with a CPL or other 2-part rotating filter. One can sometimes find cheap "jar openers" at discount stores, with a levered plastic strap to grab the edges of a jar lid or lens filter. This is my favorite butt-saver.

To avoid such aluminum welding in the future, run a bar of soap lightly around the male threads. Prevention is the best medicine. Except maybe chicken fat.

Sandy Hancock · 03-17-2012, 11:48 PM

Originally posted by monochrome

I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter.

That's not going to work with a polariser though, is it?

03-17-2012, 06:57 PM	#1
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,272	Welded filter thread Brand new Heliopan circular polariser on a nearly new Sigma EX 17-50. I just can not get the thing off. It's been a week now :-( Part of the problem is of course difficulty getting purchase on the thin rim that threads into the lens. Strength is not the issue. I have tried carefully applying a penetrating lubricant to no avail. Any suggestions??

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03-17-2012, 07:02 PM	#2
Ex Finn. Site Supporter Join Date: Nov 2007 Location: Southern Maryland. Espoo. Kouvola. Photos: Gallery \| Albums Posts: 7,975	Rubber band around the filter or wearing rubber gloves might help with traction.

03-17-2012, 07:11 PM	#3
pezmaker Senior Member Join Date: Jul 2011 Location: Madison, WI Photos: Gallery \| Albums Posts: 276	I had this problem with a polarizer and a close focus lens filter locked together. If Ex Finn.'s trick doesn't work (or if you don't have those components), toss the offenders in the freezer for a while, it should shrink the bits enough to easily pull apart. Again, just my experience ONE time... No matter what I tried, I couldn't get them apart. I put them in the freezer and it was as if they were never locked together.

03-17-2012, 07:16 PM	#4
jpzk Site Supporter Join Date: Jan 2009 Location: Québec Photos: Gallery \| Albums Posts: 8,251	I did something similar as pezmaker ... I put an ice cube tray on the kitchen table, covered it with a thin cloth and put the lens with it's filter side directly on the cloth ... left it there for 5 minutes (or longer ?) andthe filter could be unscrewed with no effort at all. This was suggested by a PF member here. JP

03-17-2012, 07:16 PM	#5
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	If you can't get enough of a grip with the rubber band, try one of those rubber sheets that they sell to help with opening bottles - they are more forgiving. Also, the temperature trick works but be careful with the lens - personally, I'd try the fridge first.

03-17-2012, 07:18 PM	#6
pezmaker Senior Member Join Date: Jul 2011 Location: Madison, WI Photos: Gallery \| Albums Posts: 276	Fair point. This was just a "macro" filter and a polarizer, I don't know if I'd been so quick to throw a lens in the freezer. Well, at least a new one. My M 1.7 or helios 44-2, wouldn't hesitate, but who knows with these new fangled auto focus lenses

03-17-2012, 07:22 PM	#7
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,272 Original Poster	I'll try the rubber band, but I really like the cooling idea. I'll give it a go as soon as I get home. Thanks

03-17-2012, 07:29 PM - 1 Like	#8
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Originally posted by pezmaker Fair point. This was just a "macro" filter and a polarizer, I don't know if I'd been so quick to throw a lens in the freezer. Well, at least a new one. My M 1.7 or helios 44-2, wouldn't hesitate, but who knows with these new fangled auto focus lenses Electronics can be finicky that way.

03-17-2012, 07:42 PM	#9
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	Another thing to keep in mind is that strength is not your friend here. The tighter you grip the more distorted the threads get and thus bind. Use the least amount of force you can, rubber band or rubber sheet helps to get purchase without gripping tightly. Avoid squeezing from the sides if you can, instead put the rubber sheet on top and gently try to twist it.

03-17-2012, 07:46 PM	#10
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Originally posted by jatrax Another thing to keep in mind is that strength is not your friend here. The tighter you grip the more distorted the threads get and thus bind. Use the least amount of force you can, rubber band or rubber sheet helps to get purchase without gripping tightly. Avoid squeezing from the sides if you can, instead put the rubber sheet on top and gently try to twist it. Excellent points!

03-17-2012, 07:48 PM	#11
monochrome Loyal Site Supporter Join Date: Mar 2008 Location: Working From Home Photos: Gallery \| Albums Posts: 26,276	I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter.

03-17-2012, 07:52 PM	#12
Docrwm Veteran Member Join Date: Sep 2010 Location: Somewhere in the Southern US Photos: Gallery \| Albums Posts: 12,285	Originally posted by monochrome I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter. You might think about adding that one to this thread: https://www.pentaxforums.com/forums/pentax-camera-field-accessories/171466-wh...lped-most.html

03-17-2012, 07:53 PM	#13
Philoslothical Veteran Member Join Date: May 2011 Posts: 1,889	Lenses get a lot colder than the freezer during normal winter use outdoors. I wouldn't worry much about the cold, but condensation could be an issue if it's humid in the house. Putting the lens in a plastic bag before freezing it would help mitigate this. The plastic bag might even help to grab the filter when it's taken out.

03-17-2012, 08:12 PM	#14
RioRico Veteran Member Join Date: Jun 2008 Location: Limbo, California Posts: 11,263	Originally posted by monochrome I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter. That trick works fine with a fixed filter, not so fine with a CPL or other 2-part rotating filter. One can sometimes find cheap "jar openers" at discount stores, with a levered plastic strap to grab the edges of a jar lid or lens filter. This is my favorite butt-saver. To avoid such aluminum welding in the future, run a bar of soap lightly around the male threads. Prevention is the best medicine. Except maybe chicken fat.

03-17-2012, 11:48 PM	#15
Sandy Hancock Moderator Site Supporter Join Date: Feb 2012 Location: Adelaide Hills, South Australia Photos: Gallery \| Albums Posts: 11,272 Original Poster	Originally posted by monochrome I've had success with one of those flat rubber bathtub drain stoppers I got at WallyWorld - no squeezing at all, just even pressure with the palm all the way around the face of the filter. That's not going to work with a polariser though, is it?