[GreenKeys] 28 typing reperf help needed

[Jack]

Those typing 28LPR’s are a nightmare to try to fix. Glad it worked  for you. I saw

many a commercial TTY user give up on the printing on those things and just let them

punch away.  The fact that the hammers are also unobtanium doesn’t

help.

 

Jack K2TTY

 

 

 

 

 

From: GreenKeys [mailto:greenkeys-bounces at mailman.qth.net] On Behalf Of Nick England
Sent: Friday, November 18, 2016 12:31 PM
To: Greenkeys <greenkeys at mailman.qth.net>
Subject: Re: [GreenKeys] 28 typing reperf help needed

 

Problem fixed thanks to excellent advice from a couple of experienced greenkeyers. Both Ken Gartland and Dave Williams had seen this problem years ago and sent the two suggestions below. I'm writing this note so the info will end up in the archives. 

Short of disassembly (which both agreed would probably leave me babbling in a straightjacket), the suggested procedures from the olden days is to try the following -

1) Slightly pry apart the U of the pushbar and then push the pushbar to the proper pinion tooth location. This didn't work for me because my reperf was stuck with the pinion all the way at the bottom of the U. So option #2 is:

2) Summon up your courage, utter a short prayer in the direction of Skokie, and push really hard on the pushbar while holding the eccentric pinion in the proper position. Et Voila! My pushbar and eccentric are now engaged in proper sync and my typewheel will move 0, 1, 2, or 3 rows depending on pushbars 1 & 2. My reperf lives to punch another day...

Many thanks to Ken and Dave for their experienced guidance. This list is really great and I continue to enjoy all the trouble you folks have helped me get myself into.

Cheers,


Nick England K4NYW

www.navy-radio.com <http://www.navy-radio.com> 

 

On Thu, Nov 3, 2016 at 9:49 PM, Nick England <navy.radio at gmail.com <mailto:navy.radio at gmail.com> > wrote:

Howdy folks - My problem is in the axial positioning mechanism for the typewheel of a M28 typing reperf (LPR). Maybe someone has encountered this or a similar problem and can provide some guidance

Background - There are two eccentrics on a common shaft that control how far the type wheel moves in-out. The lower eccentric (156278) has gear teeth that engage teeth on the No.1 push bar and move the typewheel 0 or 1 rows. The upper eccentric (156288) has gear teeth that engage teeth on the No. 2 push bar and move the typewheel 0 or 2 rows.

Voila - if both push bars are disengaged then the typewheel stays at row 0. If both push bars are engaged the typewheel moves to row 3, etc.

So much for theory. My problem reperf has somehow gotten the No, 1 push bar's  teeth 180 degrees out of sync with its eccentric. The default position with both push bars disengaged has the outer eccentric rotated so that the rest position is at row 1 instead of row 0. This also means that the No. 1 push bar won't move at all because there aren't any teeth on that portion of the eccentric for it to engage. No. 2 push bar and eccentric work OK.

Now the big question -  How do I get No. 1 push bar and it's eccentric back in sync? It looks like serious major surgery to get in to disassemble the eccentrics because all sorts of other thingamabobs would need to be removed to get to it.

For reference, there's a useful drawing here - 
http://www.navy-radio.com/manuals/tty/28-LPR-axial.pdf

 

Any helpful advice will be greatly appreciated!
Thanks in advance-


Nick England K4NYW

www.navy-radio.com <http://www.navy-radio.com> 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20161118/9a919792/attachment-0001.html>