The problem with silver solder is that the joint has to be heated to red heat, thus destroying the temper of the spring steel typebar and potentially weakening it.  If the type slug has slipped slightly during the process, it would be difficult to undo the joint and do it all over again.  A soft-soldered joint is slightly elastic, thus acting as a shock absorber when the typeface hits the paper.  A hard-soldered (silver solder joint) is not.  Possibly you could use lead-free solder (tin), but I do not know if it has the same elasticity.  Also, it does not have the same plasticity/temperature range as lead-based solder so may be more difficult to work with in this application.  Finally, regarding lead being a poisonous metal - yes it is, but in the very small amounts being used it is hardly likely to cause you any problems.  After all, until about ten years ago all the copper drinking water pipes in British homes were soldered together with tin/lead, and most still are.  I don't think anyone ever died from it !

Thanks, Pete! This helps a lot. It confirms what I thought the problem is: on my machine, at rest in lowercase, the universal linkage sits in the middle, in the 45 degree part of the slot, so when it starts to move, it goes down first. 

From your photos, it looks like the bar angles down somewhat, certainly more than mine, and may have a slight angle in the end piece vs the rest of the shaft.



I'll go look around mine a bit more in comparison. I don't want to start bending things if I can avoid it.

Rob, Sorry for the delay on my end...

"  When your machine is in lowercase, and you type, does it stay in the upper position in the slot and immediately start pulling the drive bar, or does it move down to the lower (caps) position before pulling ? "

Yes, in lower case it stays in the upper position in the slot and immediately starts pulling the drive bar.  (See the first 2 photos, below.)  These 2 photos are with the machine mostly flat on the table and shift in lower-case and no key-top has been struck,

Following in the next Post are some more photos.  Hope these help.
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And is it possible to only use tin for soldering ?
Because lead is toxic...