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08-7-2014 11:12:53  #1


Ball Retainers

I began to repair a machine last night, and for the first time that I can remember I encountered a set of ball retainers that didn't have anything to keep the ball bearing in place once the retainer is removed from the carriage rail. In other words, the moment you pull the retainer out the bearings will drop out - and if you're not careful - roll off the table and into the nearest floor drain (no, that didn't happen, but it is a possibility). Has anyone come across these types of retainers before? I hate dealing with ball retainers as it is - they're always a pain in the ass to get back in - but now I've got to also load four bearings into it while I slide the carriage back on? Sometimes I hate working on typewriters!


The pronoun has always been capitalized in the English language for more than 700 years.
 

08-7-2014 16:44:00  #2


Re: Ball Retainers

Hello Uwe !  Olivetti Lettera by any chance ?  What you do is stick the balls back into their retainers with a dab of grease (you can improvise a miniature grease gun by using a syringe without the needle).  You will still have a wonderful time as you get three balls in place only for the fourth to drop out as you try to slide the carriage back into place, but at least the grease makes it possible - after a few attempts !  You can always wipe the surplus grease off the carriage rails once everything is reassembled.

 

08-7-2014 21:57:51  #3


Re: Ball Retainers

Thanks for the tip! I was hoping you would offer some words of wisdom. It's not a Lettera but a first generation Hermes Baby, which I'm now struggling to get the carriage off of. The end of the carriage seems to be hitting the upper part of the escapement; I can see that removing the carriage's end plate would solve that, but I'm having a hard time believing that it is the right solution given how much work it would be to do that.


The pronoun has always been capitalized in the English language for more than 700 years.
     Thread Starter
 

09-7-2014 11:13:51  #4


Re: Ball Retainers

Uwe wrote:

I began to repair a machine last night, and for the first time that I can remember I encountered a set of ball retainers that didn't have anything to keep the ball bearing in place once the retainer is removed from the carriage rail. In other words, the moment you pull the retainer out the bearings will drop out - and if you're not careful - roll off the table and into the nearest floor drain (no, that didn't happen, but it is a possibility). Has anyone come across these types of retainers before? I hate dealing with ball retainers as it is - they're always a pain in the ass to get back in - but now I've got to also load four bearings into it while I slide the carriage back on? Sometimes I hate working on typewriters!

Ah, Uwe--ball retainers. Count your blessing, though, for without them carriages would be a lot more difficult to return. In the bicycle world we often threw away retainers and replaced them with loose balls when overhauling hubs and other bearings but we could do that because the balls were trapped running in a circle. (The idea was both to get better bearing support from more balls and to eliminate the friction of the balls rubbing on the edges of the retainers.)

With the straight run of a typewriter carriage, though, the balls would quickly roll out of the proper positions and either not give support across the whole length or actually fall out the ends. Sometimes the retainer is a single long piece that holds two or three balls separated for good support and other times they are very small star-shaped pieces holding a single ball each; the teeth of the stars mesh with holes along the carriage length so they stay in relative position as they roll.

The latter design is a lot more frustrating to get back in place because they have to be "timed" in relation to that line of holes. Put one in too soon and it'll fall out the far end when the last one goes in the near end; too late and it won't give proper support to that first end. Try carefully noting their positions before you take it apart. Even the one-piece designs probably are keyed to a position.

The grease idea is a good one. I'm sure the factories had a strict sequence of assembly and jigs to hold things in place. I don't know the repairman's tricks.

 

09-7-2014 11:47:13  #5


Re: Ball Retainers

Since I do a fair amount of repair work I've dealt with plenty of ball retainers in the past, and have become fairly good at dealing with them, but the retainers used by this Hermes Baby was a first for me because unlike all the others that I have encountered these don't have anything to hold the ball bearing in the retainer when it is removed. When I bought this machine I noticed a bit of a wobble in the carriage and looked down its rails; sure enough, one of the bearings is missing because whoever last had it apart didn't know what they were doing and had not correctly installed the retainers so that they would remain within the rail during the normal range of the carriage's movement.  


The pronoun has always been capitalized in the English language for more than 700 years.
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