I got bored on Xmas day so I started poking and prodding that Underwood Noiseless Standard that I bought recently. To my surprise, and despite all the rust, it's coming apart pretty easily. Of course, I haven't gotten the carriage off yet. But I did get the platen and feed rollers out and I found the serial number, finally. And the only thing I've broken so far was the draw tape (which broke off right at the metal hook so I'll have to make up another to get this working later)
   For the benefit of any others who might be scratching their head, as I was, trying to find the serial number, here's a pic of my project with the platen roller off and the location highlighted.
    From the typewriter database site this looks like a 1940 Underwood Noiseless Standard, s/n N5226971.

The serial number is on the lip facing the back of the machine, and it is written upside down so you can read it when craning your head down from the top.

And update is in order (as of 11 Jan 2016) and work on this project is continuing apace. I got the next major piece off now, that's the "shift assembly" -- the part with the lower half of the carriage rail on it that you can see in the picture above.
   And I'm slowly working things loose. I had to take off the shift assembly to get some access to all of the intricate typebar linkages. And I've gotten those oiled now and worked free. So all of the keys are working now, both upper and lower type slugs! Today I'm going to get the ribbon vibrator arm back on. I got it off Saturday and oiled the shaft so it works easily now, but the arm is in a really tight spot.
   I've got the drum unit out of the machine and I'll need to take a look at oiling that and working it free as, like everything else on this machine, it was frozen with rust. Then I'll put the drum unit back in and check the ribbon movement. And then I think it will be time to spend a few moments in the kitchen with a toothbrush and actually clean the covers on this thing.  I need to do that before I put the shift assembly back and then start concentrating on the carriage. And I'm hoping the escapement will work correctly. I got it so it moves, but I don't know if it's supposed to move easily or if it's supposed to have some drag. I think this typer uses a silent clutch for the carriage return instead of a ratchet (Too much noise with a ratchet I guess).
   This is a fantastic machine! The design and engineering are top-notch. They didn't cut any corners, I can tell that from the tear down. Example: they used sixteen (16) little roller bearings for the carriage movement. First, roller bearings are superior to ball bearings, and second, I'm sure some accountant could have asked them to reduce it to eight roller bearings, and that would have worked, but 16 is so much more stable and tough! The back cover is cast iron! So of course it's heavy. This is the Cadillac of 1940 typer design.
   So I'm pecking away, cleaning up rust and oiling things. I just bought another bottle of gun oil I'm going through it so fast. Do you know how many joints there are on every one of those typebar linkages?
   More later.

treefaller, I salute you! If you can rescue that thing, I should be able to get a much more gently used one working. I was spoiled by beginner's luck whereby a number of "broken" machines required the most minor tweaks to get typing again so I began thinking typewriter repair was a piece of cake. Lately some more needy machines have steadied me - and monopolized my work area in states of arrested repair. 

Since there are now three of us peering at the same model, approximately, a simple question: the double-type-head thing. I think every type bar does double duty, coming in high for one key and low for another? If there is no stupid question this must be the one that tests the rule, since either this is so well known it's a boring observation, or nuts. But these are classic reasons for being afraid to ask stupid questions. 

One thing your example has which mine lacks is a proper set of keys! There seems reason to believe the small blank keys were original and it was a teaching machine, but I still have doubts.... aha!  Having such annoying small slick targets would be consistent with a teaching machine: not only would it force the the student to memorize the keyboard, it would force her to develop such accurate aim that any machine with normal size keys would thereafter seem easy!  If I get this working I shall return to typing school. It is Kismet. Most people at work can't even touch type and I feel slick like a tyro, but in a proper typing school I would soon be called to the office and told my progress was not satisfactory at all, and the school was having second thoughts about admitting me. 

Heh, ztyper. I understand you frustration  with that ribbon threading. Tip: use a pair of tweezers to fold the ribbon back so it goes around the corners until it drops down into the main channel. Good luck!

And here it is 3 Feb 2016 and I'm officially ready to say I'm done now. The old girl is fixed and operating again. All I have to do now is exercise her for a month or so, which I am beginning to do.  I just noticed that I haven't posted an updated typing sample, so I'll get to that soon. It's typing pretty nicely now, and it certainly it quiet! The keyboard touch is something I'm still getting used to, so I'll pound on it for awhile before venturing my permanent opinion on Noiseless typewriters. In the meantime, here is a before and after pic of the old girl, whom I call "Norma Desmond" (cf. Sunset Boulevard)
This is a 1940 Underwood Noiseless Standard, s/n N5226971, with Distinctive Elite font.
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