I would not sand that. If it worked then, then it should work now. i think that your problem may be that you are not hitting the keys hard enough. Try hitting them harder. Also, is the platen really hard and non grippy? It may have shrunk. AND  I think that some keys may be out of alignment.

Thank you very much for all your useful advices

TypewriterGuy wrote:

I would not sand that. If it worked then, then it should work now. i think that your problem may be that you are not hitting the keys hard enough. Try hitting them harder. Also, is the platen really hard and non grippy? It may have shrunk. AND  I think that some keys may be out of alignment.

Hello TypewritterGuy. I am sure the I am hitting the keys hard enough, in fact, there is a point for every type where it doesn't matter how hard I hit the key, the impression does not improve. Take a look, for example at letter "v" in the words "every" and "conservation", with respect to the sample line "vvvvv". The first time I was hitting the key with a medium force, in the sample line, I was pressing it very hard.


With respect to the platen. It is grippy enough to "catch" the paper when I roll it. I don't know if that should be enough... how can I know its optimal hardness point?? I mean, how cna I test it??.

Uwe wrote:

The first thing I would do is work on the vertical alignment to make sure that all the characters are on the same baseline. This adjustment alone can have a profound effect on the overall type quality. Vertical alignment is achieved by adjusting the carriage travel when the shift key is pressed.

[...]


I'm assuming that if your ring was worn you would have very dark characters because some letters would be striking the page too hard, and I don't see any evidence of that in your type sample, which is one reason why I think it would be a huge mistake to alter it in any way. Remember, if you make the ring thinner, you would have to adjust the cylinder (platen) too otherwise your slugs will end up shredding the ribbon and destroying the platen's rubber. Good luck.

Hello Uwe, thank you very much for the vocabulary lesson.

Your advice seems much clever than my crazy idea. I have no idea how the heck I can adjust the alignment. Could you please try to give me any kind of tip? (Meanwhile I will try to find by myself) I give you some pics showing a machine exactly like mine:

Pic 1

Pic 2

Pic 3

Pic 4

Pic 5

Pic 6


In any case, my main concern is that if I adjust the machine to the point where I solve the problem with the types that print lightly, I will create a problem with the types that print well right now. In the photo of the first message, yuo might not see clearly, but the difference in the thickness of the ring is quite big ( I would say almost 1mm in the worst case).

I'm familiar with your typewriter. I have a number of Underwood portables from the same era including the Universal version of your machine, and a Champion with the Sealed Action Frame that replaced your model.
 

None of my machines have a ring that looks like yours, which also appears to be missing the small cover under the type guide. It's difficult to tell from your photo, but is the ring on your machine a separate piece that is attached to the segment as opposed to it being a part of the segment as on my machines (see photo below)?



Something else: take a look at your photo of the v and o typebars. If you look at the backside of the each typebar you can see the flattened edge, which is caused by slamming other typebars into to. This happens when the typebars jam, but if the typewriter was abused (like when a child pounds on the keys) it can also cause the typebars to bend out of shape. Given what I see in your photos, it's something else for you to check.

Again, I wouldn't touch the ring until I was absolutely positive that all of the typebars and slugs were perfectly straight relative to each other, and the upper and lowercase type had been correctly aligned. 

Oh, just read the rest now. Your problem might be dirt in the type bar slot, AND/OR alignment. Try getting a thin wooden toothpick, or if you can, a bobby pin with the plastic stuff on the end works well too. Scrap in INSIDE the slot, and try and see if you can get any dirt out, if you can. 

Then as Uwe said, its the type bars. Im not going to tell you exactly what to do, because Im not sure, but you are going to have to carefully bend the slugs forward (I think).