When it came to me, this machine was working, with an excellent platen, but sluggish. It definitely needed a thorough cleaning and had a few quirks to iron out. Here's the punch-list I came up with on my test-drive.

* Dirty internals; needs a thorough cleaning
* Right margin doesn't work.
* Tab doesn't work. No matter what, it advances only one step
* Dirty type bars
* Very heavy action, even on lightest setting. May be partly due to lack of use and needing cleaning.
* Shift is sluggish - just needs cleaning probably
* Much of the soundproofing has been removed.
* Ribbon doesn't reliably feed to the left. Seems to feed to the right ok. Needs cleaning & retesting.
* Alignment shields flop down when you pull the carriage. They also aren't attached to the mystery levers in front of them. Maybe one and the same issue?
* Paper injector takes lots of force.

First thing's first: removing the shell to get at the internals. I very quickly discovered that the SG-1 is a wonderful machine to work on. Two knobs turned and the carriage pulls off, giving full access to the escapement and all the rear mechanisms, as well as the carriage rack, main spring, etc. A few screws removed liberated the shell easily. If this were my second SG-1, I probably could've gone from taking it off the shelf to air-compressor ready in less than 60 seconds.

(My joy may be biased by the fact that I've worked exclusively on portables for the last year).

I did have some difficulty getting the shell off the carriage, though. The Repair Bible directed me to simply remove the levers, unscrew the platen knobs and a few screws, and then everything should come right off.

The devil was in the details: The carriage-release lever was friction-fit on a tapered axel. The screw for the lever seems to be partly cosmetic and partly to seat the lever on the axel. Removing the screw does nothing.



My levers were on good and tight. I found that I could place a screwdriver between the shaft collar and the inner edge of the lever collar, twist, and (with eyes closed hoping I wouldn't break anything) pop them off. More like launched them off as they really didn't want to give in.

In retrospect, I shouldn't have used so much force. Next time, I'll put a little penetrating or very low viscosity oil in there to creep into the fitting and loosen things up a bit.

The platen knobs were not as obvious as the manual let on. It said that all I needed to do was unscrew the knobs. At first, I thought it meant to unscrew the knobs themselves from the shaft. That proved impossible (because that's not how they work). What I hadn't realized, and didn't spot in the diagram, is that, unlike any of the other typewriters I've worked on, there's no axel that runs through the entire platen and into the knobs. Rather, the knobs have a short axel that threads into the paten. Once I figured that out, and that I really needed to hold onto the platen tightly, I was able to get them off just as the book glibly described (again, with almost more force than I was comfortable with).

Disassembling the carriage also gave me a view of the rubber / cork composite rollers and their state of deterioration. (As I posted earlier). Next time I head to the auto parts store, I'll find some new rubber for these. In the meantime, though, they seem to be OK at gripping the paper I'm putting in (though there is a slight drift], so it's not a pressing need.

While I had them out, I compared the starwheel / pinions from the SG-1 and SG-3.



Here's a question for all of you: what's that spring on the back for? The SG-1 has a little hook on the end, but I can't find anywhere it would hook into. Are these springs merely to hold the silent carriage return "washer" (part D20 in the book) on?

Next up: more questions on adjusting the escapement.

Yes, the spring on the back is simply to provide a little friction so that the silent return mechanism works properly.  No real idea why the SG1 spring would have a return on the end.  It could simply be that in typical German fashion, it is to make the spring end look 'finished'.  The return was probably removed on the SG3 because either it was catching on something (cleaning brush) or found to be a totally unnecessary expense.  Just my theory 

I've started working through the SG-1 Typewriter Repair Bible. The escapement trip point was a little too far out, so I brought it in as described in the manual (page 63, procedure 1/3a step 1).

I'm having trouble doing step 2 of that procedure, adjusting when the type bar contacts the u-bar frame. It's about 1/4" too far out (which may not matter, but I like to get machines on spec first, then adjust them from there).

Here's the procedure and diagram:




I'm not sure where adjusting screw C5 is. Looking at the diagram, it sort of looks like this screw here (pointed to by the screwdriver):



But, when I look behind that, it's clearly not an adjust screw, but looks more like a guide that goes through a plate attached to the U-bar:



On both sides, the shaft of the screw that goes through the U-bar plate is bent slightly, so turning the screw effectively raises or lowers the guide.

So, question 1: What is this screw for, really?

Question 2: does anybody know where to find C5 (or whatever screw will adjust the front-back position of the u-bar)? I'm assuming it adjusts the resting position of the U-bar, but I can't find anything that does that.

Thanks!