1 of 1- typeitup
- Novice Typer
Offline - Registered: 24-10-2019
- Posts: 28
Mainspring - how tight?
Hi, I have today had the unfortunate business of having the drawbands on 2 machines spinning back and around their respective mainspring hubs while I did some maintenance (sometimes we just have clumsy days). Anyway, I have rewound the mainsprings and the drawbands have good tension again. But this got me thinking, how tight is too tight? And how much "over-tension" can 50-year-old mainsprings take?
Obviously if the carriage is flying to the left or skipping spaces when typing, that would be a sign, but I was wondering if there was a better method while actually winding the mainspring to begin with. Thanks in advance for any insight.
- skywatcher
- Moderator
Offline
- From: The Prairies of Alberta
- Registered: 14-3-2013
- Posts: 712
Re: Mainspring - how tight?
Hi Typeitup
If memory serves me correctly, correct mainspring tension should give about 2 pounds (0.9kg) force on the carriage at mid point with escapement disengaged (carriage release held with elastic band). Hope this points you in the right direction,
Sky
We humans go through many computers in our lives, but in their lives, typewriters go through many of us.
In that way, they’re like violins, like ancestral swords. So I use mine with honor and treat them with respect.
I try to leave them in better condition than I met them. I am not their first user, nor will I be their last.
Frederic S. Durbin. (Typewriter mania and the modern writer)
