1 - ztyper
- Key Master
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- From: Somewhere in New Jersey
- Registered: 01-10-2014
- Posts: 773
Mystery gears
Man do I have a lot of questions... But this is my ast one for today. I recently got an Underwood Touch-Master 5 at a thrift shop today for $20. The escapment is very clean, and it uses a chain to turn the ribbon spools (which is rather interesting). But as I looked around, I saw some gears kinda slowing down the carriage when ever I hit carriage release or tab. What are these gears for and why do they slow down the carriage? Here's a picture of what I mean.
A high schooler with a lot of typewriters. That's pretty much about it.
- Uwe
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- Registered: 12-3-2013
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Re: Mystery gears
If you've ever used a tabulator that didn't have any tab stops set, you know just how hard a carriage can slam into the right margin. Similarly, if the tab stops are far apart a carriage can pick up a lot of speed before crashing into the next tab stop. Some machines - even some portables like the earlier SM9s - used a tab brake to slow the carriage and reduce its impact. It had the side benenfit of reducing the amount of noise using a tabulator made during use, or made it a less jarring experience for a typist who was an hour past their cigarette break.
The pronoun I has always been capitalized in the English language for more than 700 years.
- ztyper
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- From: Somewhere in New Jersey
- Registered: 01-10-2014
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Re: Mystery gears
Ah, ok. That's what I thought, because both of my SM's have something like that. This was just rather slow, almost painfully. But I hardly ever use tab anyways. I guess it's better than slamming into the side of the machine, like my Royal 440 does (I can feel the entire room shake when it does that...).
A high schooler with a lot of typewriters. That's pretty much about it.
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Thread Starter- Uwe
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Re: Mystery gears
If it's excessively slow then it probably needs to be looked at. None of my Underwood Five machines exhibit that problem, so I've never had to examine the tab brake on them to see how they work. It could use a cleaning, or it could have worn parts (the SM9 for example uses cork).
The pronoun I has always been capitalized in the English language for more than 700 years.
- ztyper
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- From: Somewhere in New Jersey
- Registered: 01-10-2014
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Re: Mystery gears
Hm. It must be a cracked gear that's also worn. It's plastic, so I'm not surprised it didn't last. I wonder why they didn't make it out of something else besides plastic...
A high schooler with a lot of typewriters. That's pretty much about it.
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Thread Starter- TypewriterKing
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- From: DeepInTheHeartO', Texas
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Re: Mystery gears
These "gears" are what makes up the tabulator brake. This is actuated whenever the tab is used. They slow the carriage down so it won't hit a set tab stop with too much force. On these particular machines, Touch Master 5s, the tabulator is a lockdown type that only needs to be tapped once. It works a lot like the way an electric typewriter tabulator works. Tap it once and it will stay engaged until it hits the next tab stop. The tabulator brake is very similar to the one employed by the Underwood electric typewriters since about the fifties, only they didn't have that large plastic gear, which in every Underwood 5 machine I've seen has ALWAYS been cracked. But somehow, it still always works so I leave them alone. I hope I helped some.
Underwood--Speeds the World's Bidness
- ztyper
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- From: Somewhere in New Jersey
- Registered: 01-10-2014
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Re: Mystery gears
I realized after taking it off that it was a tabulator brake because I nearly ran the carriage off after pressing tab! I have since replaced this machine with a '49 Underwood SS.
A high schooler with a lot of typewriters. That's pretty much about it.
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Thread Starter- M. Höhne
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- Registered: 14-3-2013
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Re: Mystery gears
ztyper wrote:
Hm. It must be a cracked gear that's also worn. It's plastic, so I'm not surprised it didn't last. I wonder why they didn't make it out of something else besides plastic...
Plastic is cheaper; simple as that.
- TypewriterKing
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- From: DeepInTheHeartO', Texas
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Re: Mystery gears
That 1949 Underwood SS. I guess we all know (or should know) SS stands for "Segment Shift." And it too has a tabulator brake (I'm not sure how far back Underwood offered machines with a tabulator, but I have read somewhere that the tabulator option was made available on a typewriter in 1897). Instead of being made of plastic, it is made of metal and two small pieces of leather, and you may have discovered that it isn't the lockdown type of tab--you have to keep pressing the tab bar until the carriage completes its "jump." Well, anyway, the way these older style brakes worked was that the two leather pieces on a caliper-like mechanism squeeze a slender, spring-loaded metal strip mounted on the carriage. The harder you press the tab bar, the firmer the grip, and the slower the carriage moves.
Underwood--Speeds the World's Bidness
- ztyper
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- From: Somewhere in New Jersey
- Registered: 01-10-2014
- Posts: 773
Re: Mystery gears
Would you possibly know the root of the carriage rack grinding on the escapement pinion whenever tab is pressed? I can't figure it out and it only affects the right side. For the first half of the trip everything is fine and then that awful noise starts up...
A high schooler with a lot of typewriters. That's pretty much about it.
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Thread Starter