NikonGear'23

Gear Talk => What the Nerds Do => Topic started by: brent_e on September 24, 2016, 02:54:08

Title: 20mm f/4 AI conversion
Post by: brent_e on September 24, 2016, 02:54:08

hey folks,
new here.  thought I'd throw this up as I see a few more similar threads. 
I found this lens for what I thought was a decent price locally.  First I swapped aperture rings with a 24mm 2.8, but the fit wasn't great and I always had to adjust exposure comp.  I finally decided to do a proper job on this.  It's become one of my favourite lenses. 

Title: Re: 20mm f/4 AI conversion
Post by: richardHaw on September 24, 2016, 03:52:28

i love your machine :o :o :o

Title: Re: 20mm f/4 AI conversion
Post by: richardHaw on September 24, 2016, 03:53:32

Nice job, by the way. very clean cut :o :o :o

Title: Re: 20mm f/4 AI conversion
Post by: Hugh_3170 on September 24, 2016, 05:41:08

Ah, a proper milling spindle!  Nice to see the aperture ring being machined with the best choice of gear.  Is the three jaw on a rotary table?

Once you learn how to do the Ai conversions for oneself, a whole lot of interesting lens choices from the pre-Ai world become convenient.   ;D   Not quite so good for your bank account however.   ;)

Title: Re: 20mm f/4 AI conversion
Post by: John Geerts on September 24, 2016, 07:37:10

Cool job and impressive detailed photo's.

Title: Re: 20mm f/4 AI conversion
Post by: Jakov Minić on September 24, 2016, 09:23:57

Brent, welcome to NG!
Something tells me from your first post that you will fit in here nicely :)

Title: Re: 20mm f/4 AI conversion
Post by: Mongo on September 24, 2016, 11:21:08

There are a few ways of doing this job but yours  is by far the best Mongo has seen. Nice work, machinery and instructive images.Thanks.

Title: Re: 20mm f/4 AI conversion
Post by: richardHaw on September 24, 2016, 18:24:19

can you please show us a full picture of your milling machine :o :o :o

Title: Re: 20mm f/4 AI conversion
Post by: brent_e on October 06, 2016, 03:53:37

Hey Folks,
thanks for the kind words! 
The three jaw chuck is on a rotary table.  I'll have to look a bit further (or just take one tomorrow) for a photo of the mill.  It's a Gorton tracemaster from 50-60 years ago!  The original CNC!   haha!


thanks again

Brent

Title: Re: 20mm f/4 AI conversion
Post by: brent_e on October 06, 2016, 23:11:24

There's the old mill and lathe.