Another J.J. Short Platen installed on an Underwood Master

New one as I unpacked it

 Here are some photos of how I changed the platen with more step by step instructions than my Rhythm Touch post (11 April 2015).  Please review the photos first if you use these as a guide to help change a platen as some are out of order.

First remove the two screws on top of each end cover and remove the left end cover.  Then remove the right knob.  Remove the right end cover.  Next remove this collar. (No collar on my Rhythm Touch)

Collar

Then go to the left end and using a spring hook (or carefully use a screwdriver) pull back the line space ratchet dog and rotate the line feed release lever up as shown so it can be removed.  This is a bit different than my SS or Rhythm Touch.  On the SS there is room to remove the lever out the back beside the spring hook.

This is a better shot of the dog with the lever removed.  I started to pull the rod out.  Gently pull and twist the rod to remove it.  To start pull back on the dog lever as shown to relieve the tension against the ratchet gear.

I missed the image of the rod as it was remved.  Blogger is too flaky to even attempt to insert the photo.  This is the rod after I cleaned it with Scotch-Brite.  Steel wool could be used also.

Another out of position photo.  Blogger is not the most user-friendly blog application.  This photo belongs after the collar photo.  The first thing I did on the left end was to remove the right-most screw in the above photo.  Then I loosened the left one so the carriage release lever would hang free of the ratchet gear (also something I did not need to do with the Rhythm Touch).

This is the lever clear of obstructing rod removal.

I planned to put this photo atop the others to show the old platen.  This one is my fault for getting in the wrong position as I could not find it in my directory to put it where it belongs.  I already had photos cued in Blogger when I noticed this one.

Old on left.  New on right.  It is an optical illusion if the old one looks smaller.

After laying the platen in the carriage tray the rod is re-inserted starting the removal process in reverse.  Then put the collar back on and align the flat of the rod with the set screw.  I align the platen screws at the same time in the same position.  Tighten the collar screw and then the one on each end of the platen.

This is the new platen installed on the typewriter.

The entire process takes about 20 minutes including the time it took me to clean the dirt out of the carriage, polish the metal I missed in the first cleaning, and treating the bottom feed rollers with rubber rejuvenator.

I'm re arranging my lab at work. As soon as a bit of minor construction is completed and I get everything organized as I want this typewriter will return to the lab where I can use it for work.  

I also have my newest Hermes 3000 there.  I took that one in when I started last year.  Since it is a portable I can always find room for it.  When I need a typewriter I use it.  I only wish I had one nice typewriter with a real carriage instead of all these short ones.  I unloaded my Praxis 48 for an IBM Selectric-II because it had a short platen.  I hate file labels and writing on file tabs.  I love using a typewriter for that job.  I guess my first typewriter for 2016 will be another old Underwood full size machine with a full size platen (12 or 13 inch).  I love the 10 inch platens on portables, but office size machines need office size platens.