Typewriter Talk / Olympia SG-1 shop time

**Posted by robmck** 17-3-2023 15:34:10

Never did figure out where screw C5 is, but after a thorough cleaning, this thing is typing amazingly well; easily keeping up with me at my fastest. Wonderful typer.

Moving on to other issues: This typewriter is really loud when I have the paper guide down, in its normal position. When I turn it up, the machine quiets right down. I'm thinking it's because it's smacking against the rock-hard platen. When I adjust its resting position so it doesn't make much noise, it's more than a 1/4" off the platen and doesn't prevent paper from curling back around the platen (i.e. it doesn't do its job anymore).

It looks like there was adhesive on it at some point: Was it normal to have some acoustic felt under this when it came from the factory?

Also, anyone know what the "7.6" means on the segment cover?

Finally: The chrome on the coming off the line advance lever (in a big chunk, too). Is this really chrome, or is this a chrome-looking plastic? I.e. to fix this, do I strip it and chrome it?

Thanks!

**Posted by thetypewriterman** 17-3-2023 16:17:05

I am pretty sure that the underside of the eraser table would have had a thin layer of felt on it. Thin craft felt, stuck on with contact adhesive (as per the original) or UHU glue should do the trick. I have never seen an SG1 with '7,6' engraved in that position, but my educated guess is that it is an indicator of the shift pattern, i.e. 7.6mm between upper and lower case characters. Yes, it is chrome on the linespace lever. . A chrome-plated aluminium die-casting. You could either have it re-plated, or (cheaper option) strip off the chrome altogether, polish it and then apply a coat of clear lacquer

**Posted by robmck** 18-3-2023 21:41:54

I think you may have it. When I set my calipers at 7.6mm and set it on the type slugs, I see:

Thanks for the tips! I'll give them a try. (I might wait on the rechroming until I have more parts that need that - it's serviceable as it is now).

**Posted by robmck** 24-4-2023 12:07:31

A curious thing has happened: my typing habits have improved for not having the right margin stop.

I've left this machine on my typewriter stand for the last month, using it exclusively, tuning and finessing it as I get to know it better. Because I've still not found or made a suitable replacement for the right margin stop, I left it out entirely (much easier to do the CAD work when it's not in the machine). So, typing without a net (or margin bell), I've had to mind my right margin myself.

And, interestingly, my page layout has improved. The right margin looks much than I produced with typewriters with a functioning margin stop: more consistent line to line and nicely balanced from the right edge compared to the left margin. Since I've no bell, I attend to the line wrapping much more, without distracting myself too much from the writing. In fact, it feels less distracting than being jolted out of the flow by the bell. Maybe it's good to not rely on mechanical conveniences so much...

It almost makes me want to spend a month on one of my blind-writers... almost.

**Posted by robmck** 24-4-2023 12:12:18

That 3rd paragraph should read "... looks much better than..."

Amusingly, this mistake further illustrates the point: in the digital medium, I can write and rewrite, over and over, deleting text, adding text, etc, in place. Inevitably, I delete one too many words, but usually the built-in spelling and grammar checkers catch my errors and fix things for me. This ironically leads to more mistakes as I keep relying on the conveniences of the digital medium to help me.

On a typewriter, working without a digital safety net, I tend to work more thoughtfully and make fewer mistakes.

**Posted by Pete E.** 24-4-2023 13:37:35

Each of the type-slugs are engraved with the 7,65 as well.

**Posted by Pete E.** 24-4-2023 13:46:57

And the segment plate on my 1961 SG1 :
.

**Posted by robmck** 01-5-2023 19:33:54

I had some time this weekend to do a little 3D modelling and successfully 3D printed a new right margin stop body to replace the crumbling one that came with the machine.

On the left, the margin stop body from my SG-3 (which I used as reference), and on the right, my 3D printed version in PLA:

Here the two are fully assembled in the same order, with the remains of the original margin stop body on the far right:

Fully assembled and mounted:

I've only written a few pages on it (some with a narrow column), and so far it seems to be working fine, though it's only printed in PLA. I suspect that will hold fine as the right margin doesn't experience heavy loads: it only engages the line lock and triggers the bell hammer. It doesn't actually stop the carriage (the SG-3 works this way too). The left margin stop, however, does get the full force of the carriage return, but that one's metal seems to still be in sturdy shape. I wonder if it was replaced more recently than the right stop.

This was my first attempt at a replacement part for anything, so it pushed my skill and the tolerances of my printer a bit. If I were more patient, I'd probably have iterated on it a bit more so that it worked absolutely perfectly without any cleanup, but instead, I ended up just using files and an x-acto knife until I was satisfied with how it was working. It's a prototype, after all, and because it requires supports, there will always be some cleanup anyway.

I've posted the model on Thingiverse if anyone needs to print their own: Olympia SG-1 / SG-3 replica right margin stop body by robmckaughan - Thingiverse

**Posted by thetypewriterman** 02-5-2023 03:53:17

Very impressed with your printed margin stop. This is definitely the way forward

**Posted by Pete E.** 04-5-2023 11:14:30

Rob, is another material option the use of ABS (Plastic) ?. Do 3d printing folks use ABS ?