Eiki NT1 Threading key

[John Taylor]

Hello everyone, I am new here and hopefully, looks a good place for help.
I have been a collector of film for around 10 years, (almost), I mainly collect 16mm but also have some super8.
I have an Eiki NT1 which is in good clean condition but have noticed that the threading key doesn't pop back to it's original position when the film is threaded, I have to give it a helping hand. Also the the little loop restorer seems to want to take off, once it goes, it keeps going around and round. Would anyone be able to give me some advice on what the problem may be please?

[Nantawat Kittiwarakul]

Probably sticky mechanism/linkage inside. The exit roller (the last one on the rear) is linked to the self-threader latch. When pulled it should release the latch and let the parts pop back, but I believe that all lubricants in linkages/pivots had been dried out after decades of use.

In a pinch you may try spraying some lubricants around those linkages to help freeing them up. But some proper service work (total disassembly/cleaning/lubrication/adjustment) would be eventually needed later.

Regarding loop restorer roller, all I can say is that it's very, very fiddly to adjust. You need to move the rear sprocket plate a tiny bit back & forth to adjust the lower loop size. When properly set it should let one perforation to slip without moving the roller. But losing one more perf should make it to activate. Once completed it should give you 2-perf clearance. Hope this helps.

[John Taylor]

Thank you for your reply, sounds very fiddly to take linkages apart but I will have a closer look.
what is the rear sprocket plate exactly please?

[Nantawat Kittiwarakul]

Thank you for your reply, sounds very fiddly to take linkages apart but I will have a closer look.
what is the rear sprocket plate exactly please?

I mean the rear sprocket, this one.😁


The actual sprocket teeth is the metal plate that lies behind the plastic cover (unfortunately not visible in the pic - but hope you get the idea) that engages with the film perforations, held in position by the screw in the middle. To adjust its position relative to the pulldown claw you'll need to slightly loosen this screw, just enough to move the plate behind around.

Once again, this is a relatively fiddly/delicate to adjust. Moving it only 1-2 millimeters will make a HUGE difference. However if you're so dedicated, this is your visual guide...


This is how the bottom loop would look like at the largest possible size when the pulldown cycle completes, with that 2 perforations clearance mentioned earlier. Note the ample distance between the film & the loop restorer roller.


And this is how the bottom loop would look like at the smallest possible size - at the start of the pulldown cycle with only 1 perforation clearance. The film might be just in contact with the loop restorer roller, but not enough to activate it. Only when losing one more perforation this roller will activate. The loop will then grow back to the size of the previous picture.

BTW although mine was made with self-threader function, but since I had to encounter films with various condition including folded/damaged/twisted/warped leaders (or NO LEADERS at all😰). Those films with such leaders would be next to impossible to automatically threaded through. After lots of failed threading and further damaged leaders I ultimately decided to ENTIRELY remove its self-threader guides and use it as a manual threader machine instead. In the end I seems to prefer it this way.

[John Taylor]

Thank you Nantawat, this is very good information, i will have a good look and see what i can do. My only concern is if i adjust something and make things worse as there doesnt seem to be anyone here in Cornwall who can repair these projectors anymore.