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Later Type II crank will not pull up to subtract position
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AuthorMessage
Patrick01
Joined: 16 Sep 2024
Posts: 2
PostPosted: Mon Sep 16, 2024 10:48 pm   Post subject: Later Type II crank will not pull up to subtract position

Hello everyone! I recently got a Type II that works completely fine. All tens will carry on the top registers, carriage good, easy to turn, clearing ring good, sliders for setting register easy to slide and all feel the same.

However: When I got it, first thing I saw was the crank was 180 out of position. Pulled taper pin, revolved back to proper "at rest" position and re-inserted the pin. The major problem is the crank will not lift. No wiggle room in it.

I have excellent mechanical skills (and small tools) but I hesitate removing anything to look. Before doing so, I'd like a few guesses as to what I might encounter trying to free the crank. I saw another post where someone shook it and suddenly the crank would rotate, Murff mentioned the tens bell.

Any and all replies will be welcome, and answered!

Thanks!

Pat Caldwell
Patrick01
Joined: 16 Sep 2024
Posts: 2
PostPosted: Wed Sep 18, 2024 12:03 am

UPDATE: After much studying of exploded diagrams, viewing animations, reading the service manual and some of the posts of others here, I got my mini tool kit and my tweezers and jumped right in.

Took off bottom and the main housing. On the bottom of the zero positioning disk where the bottom of the main shaft has the pin through it was, was nasty with some sort of dried lubricant. After cleaning with alcohol, drying, and a drop of watch oil with a toothpick in the affected area. Also a bit of lube at the step drum positioning fork and cam. Install main housing.

Works perfectly...glad I started at the bottom instead of removing crank and clearing ring...

Pat
Kmcqueen
Joined: 14 Apr 2023
Posts: 38
PostPosted: Thu Sep 19, 2024 5:11 pm

Good job - it's amazing how solid some of the grease can lock those parts together. My first curta was completely frozen solid and I would've bet money that something mechanical had failed badly. All it took was slowly taking apart and cleaning and re-lubing everything. I really lucked out. I've posted product before this before but some camera guys at my job swear by this grease.

https://www.microlubrol.com/MicroLubrol-Helimax-XP-Camera-Lens-Telescope-Optical-Instrument-Grease-1-oz.aspx
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