atkelar | Triumphator CRN-1 - Part 3 @atkelar | Uploaded February 2023 | Updated October 2024, 19 hours ago.
And now: Part 3! The conclusion!
Some time in 2022, I decided to get myself a mechanical calculator; you know, one of those impulse e-bay buys. It does work well enough when you are after restoration items, those come cheap enough.
The CRN-1 here is an East German model from the mid 1950s; it features all the regular mechanical calculator functions I am aware of and - in addition - the "R" button. It is "CRN-1" after all, not "CN-1". And yes, that is literally the only difference between the two models, even though the CRN-1 has a different case to accomodate the mechanics behind that button.
The progress within this episode: Connecting the counter drum with its reversing gearset, rebuilding the carriage assembly - with all the numbers and associated stoppers and carry flags and interlock connections. People keep asking me: how do I know where the parts go? Well, sometimes, I have to just try... and try... and try again! There was one particular part in the stack of 13 digit wheels that made the surrounding ones ever so slightly different. I really had to rebuild that section three times over; it didn't yield anything interesting visually tough, since all of the action was nested within a nest of springs to begin with; stage hand's fingers on top didn't provide a clearer view... After combining the carriage with the main unit, I glued the broken part to the axle, since these two need a sturdy connection and I didn't dare to use a pin in the glued metal. I can always drill out the epoxy if I need to, much easier than the old pin for sure. The final part is some thourough testing and tuning. I found two issues with the gearing, both of which are due to some of the components being a bit worn out. *maybe* it would be possible to fix them, but I rather keep them for now. Both issues boil down to the little input selection discs - the ones with the sets of teeth - and the connecting parts being a bit worn down. They aren't "snapping" into position as well as they should anymore. That makes them - sometimes - sitting on in-between numbers. It is a bit worse for the "R" button, which may or may not have to do with the broken part... I tried fiddling with all tolerances that are avialable to max out the travel reach of the involved gears, but it is as good as it gets. Any adjustment in either direction makes something else not work anyomore.
0:00 Intro / Recap / Counter Reversing Gears / Counter Drum
2:43 Carriage Moving Lever
3:09 Missing Another Spring!
4:35 Carriage Base / Carriage Movement Demo
5:30 "R" Gear Assembly
6:44 Digit Rack / Carry Flags and Digit holders
7:58 Center Standoff / Carriage Lock / Bell Spring
9:45 Closing the Frame / Standoff mishap / Counter Digits + Reset
11:25 Result Digits + Reset
12:30 Bell / Reset Lever
13:50 Carriage to Base! / "R" Part Glue + Spring / Base Plate
14:57 Setting and Interlock Explanation / Worn out Reset
16:08 "R" Button in Action! - Sorta...
17:04 Example 1: 346+892 (covers off)
17:55 Paint (by) Numbers... / Covers / Ruler
19:05 Reset Prevention Handle
19:53 Example 2: 123*25 (covers on)
20:40 Summary / Goodbye / Bleeper Reel
Music:
My Train's A Comin'
Unicorn Heads
(YouTube Audio Library)
You can support me on Ko-Fi: ko-fi.com/atkelar
And now: Part 3! The conclusion!
Some time in 2022, I decided to get myself a mechanical calculator; you know, one of those impulse e-bay buys. It does work well enough when you are after restoration items, those come cheap enough.
The CRN-1 here is an East German model from the mid 1950s; it features all the regular mechanical calculator functions I am aware of and - in addition - the "R" button. It is "CRN-1" after all, not "CN-1". And yes, that is literally the only difference between the two models, even though the CRN-1 has a different case to accomodate the mechanics behind that button.
The progress within this episode: Connecting the counter drum with its reversing gearset, rebuilding the carriage assembly - with all the numbers and associated stoppers and carry flags and interlock connections. People keep asking me: how do I know where the parts go? Well, sometimes, I have to just try... and try... and try again! There was one particular part in the stack of 13 digit wheels that made the surrounding ones ever so slightly different. I really had to rebuild that section three times over; it didn't yield anything interesting visually tough, since all of the action was nested within a nest of springs to begin with; stage hand's fingers on top didn't provide a clearer view... After combining the carriage with the main unit, I glued the broken part to the axle, since these two need a sturdy connection and I didn't dare to use a pin in the glued metal. I can always drill out the epoxy if I need to, much easier than the old pin for sure. The final part is some thourough testing and tuning. I found two issues with the gearing, both of which are due to some of the components being a bit worn out. *maybe* it would be possible to fix them, but I rather keep them for now. Both issues boil down to the little input selection discs - the ones with the sets of teeth - and the connecting parts being a bit worn down. They aren't "snapping" into position as well as they should anymore. That makes them - sometimes - sitting on in-between numbers. It is a bit worse for the "R" button, which may or may not have to do with the broken part... I tried fiddling with all tolerances that are avialable to max out the travel reach of the involved gears, but it is as good as it gets. Any adjustment in either direction makes something else not work anyomore.
0:00 Intro / Recap / Counter Reversing Gears / Counter Drum
2:43 Carriage Moving Lever
3:09 Missing Another Spring!
4:35 Carriage Base / Carriage Movement Demo
5:30 "R" Gear Assembly
6:44 Digit Rack / Carry Flags and Digit holders
7:58 Center Standoff / Carriage Lock / Bell Spring
9:45 Closing the Frame / Standoff mishap / Counter Digits + Reset
11:25 Result Digits + Reset
12:30 Bell / Reset Lever
13:50 Carriage to Base! / "R" Part Glue + Spring / Base Plate
14:57 Setting and Interlock Explanation / Worn out Reset
16:08 "R" Button in Action! - Sorta...
17:04 Example 1: 346+892 (covers off)
17:55 Paint (by) Numbers... / Covers / Ruler
19:05 Reset Prevention Handle
19:53 Example 2: 123*25 (covers on)
20:40 Summary / Goodbye / Bleeper Reel
Music:
My Train's A Comin'
Unicorn Heads
(YouTube Audio Library)
You can support me on Ko-Fi: ko-fi.com/atkelar
