Скачать или смотреть How to fix stiff focus ring in Nikkor Pre-Ai 50mm 1:2

In this video I will show how to fix the stiff focus ring in Nikkor Pre-Ai 50mm 1:2, and I made myself a special tool for unscrewing the narrow front ring on the focus ring, when that ring is off then it's possible to unscrew the very little set screw, and then unscrew the very front ring and in that way take the whole lens assembly out and only work with the focus assembly.

When working with helicoid's, it's VERY IMPORTANT! to set a mark where the helicoid's is separated, because the repair manual (if one have it.., I don't have it) does not tell those thing's.

You can of course also before you take it apart, measure the focus assembly (I show it in the video) and in that way maybe assemble the focus system correct,
(it will maybe take you much longer time when do it in that way..).

I did some small error's when assemble, but I corrected them in fast speed ;-)

I use lighter fluid to clean the focus helicoid's, and then lubricate them again with #10 helicoid grease from Japan Hobby Tool, now my lens is nice and run's very smooth.




Here are some link's to different repair tool's:


Japan Hobby Tool rubber cone:

https://www.amazon.com/Japan-Vacuum-C...


18 different size rubber repair tool's:

https://www.amazon.com/Sizes-Lens-Fil...


Divider Caliper Wing Compass:


https://www.amazon.co.uk/Divider-Cali...





You can also buy this set.

Lens Repair Set with pointed, flat, half flat tips:


https://www.amazon.com/dp/B00QRPWCN0/...



JIS cross head screw driver's:


https://www.amazon.com/Moody-Tools-58...


Or this set, that is the set I use:


https://eustore.ifixit.com/en/Tools/D...


Lens cleaning wipes (PEC-PAD):

https://www.amazon.com/dp/B0161VIZZ8/...