Pentax 67 Rear Converter Flange Removal

slickrock · 07-17-2021, 02:35 PM

Does anyone know how to remove the lens flange on a Pentax 67 Rear Converter? There are three small screws on the converter body that I have removed, however the flange still cannot come off.

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**ProfessorBuzz** · 07-19-2021, 05:11 AM

Have you tried wiggling it around the circumference? eg rotation?
Just curious.. but why are you taking the flange off?

slickrock · 07-19-2021, 09:14 AM

Yes, I have tried wiggling it, pulling it, on and on, with no luck. The reason? Well, this is somewhat embarrassing. The picture I attached is of a 2X converter, but the one I need to remove is on a 1.4X converter. Some 4 years ago I somehow did managed to remove the flange and attached a connection ring for my TEC 140 telescope Field Flattener; the flange was then reattached to hold the ring (the ring is designed to hold a Pentax 67 camera, so it holds the 1.4 rear converter perfectly). Now, 4 years later I want to remove the ring, but I cannot for the life of me remember how I took the flange off.

slickrock · 07-19-2021, 09:21 AM

The attached photo shows the TEC connection ring on the 1.4X converter.

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**ProfessorBuzz** · 07-19-2021, 10:51 AM

Doesn't the TEC ring rotate 45 dgrees or so to come off the external bayonet of the converter? I don't know if there is an inner/outer on the TEC one. My Astro-Physics one has the external bayonet.

slickrock · 07-19-2021, 01:36 PM

No, unfortunately the TEC ring has no bayonet openings. The ring fits to the outside of the lens bayonet; that's why the flange (or bayonet) needed to come off first.

**ProfessorBuzz** · 07-20-2021, 09:26 AM

Hmmm... can you thread the TEC down off the bayonet?

slickrock · 07-20-2021, 01:02 PM

Got it!

I had to take the converter completely apart in order to get the bayonet off.

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07-19-2021, 05:11 AM	#2
ProfessorBuzz Loyal Site Supporter Join Date: Feb 2018 Posts: 1,903	Have you tried wiggling it around the circumference? eg rotation? Just curious.. but why are you taking the flange off?

07-19-2021, 09:14 AM	#3
slickrock New Member Join Date: Jul 2021 Posts: 5 Original Poster	Yes, I have tried wiggling it, pulling it, on and on, with no luck. The reason? Well, this is somewhat embarrassing. The picture I attached is of a 2X converter, but the one I need to remove is on a 1.4X converter. Some 4 years ago I somehow did managed to remove the flange and attached a connection ring for my TEC 140 telescope Field Flattener; the flange was then reattached to hold the ring (the ring is designed to hold a Pentax 67 camera, so it holds the 1.4 rear converter perfectly). Now, 4 years later I want to remove the ring, but I cannot for the life of me remember how I took the flange off.

07-19-2021, 10:51 AM	#5
ProfessorBuzz Loyal Site Supporter Join Date: Feb 2018 Posts: 1,903	Doesn't the TEC ring rotate 45 dgrees or so to come off the external bayonet of the converter? I don't know if there is an inner/outer on the TEC one. My Astro-Physics one has the external bayonet.

07-19-2021, 01:36 PM	#6
slickrock New Member Join Date: Jul 2021 Posts: 5 Original Poster	No, unfortunately the TEC ring has no bayonet openings. The ring fits to the outside of the lens bayonet; that's why the flange (or bayonet) needed to come off first.

07-20-2021, 09:26 AM	#7
ProfessorBuzz Loyal Site Supporter Join Date: Feb 2018 Posts: 1,903	Hmmm... can you thread the TEC down off the bayonet?