Results 1 to 7 of 7

Thread: Parker 21 repair attempt

  1. #1
    Senior Member azkid's Avatar
    Join Date
    Mar 2018
    Location
    Colorado, USA
    Posts
    1,369
    Thanks
    2,325
    Thanked 1,112 Times in 530 Posts
    Rep Power
    3

    Default Parker 21 repair attempt

    So I bought a bunch of Parker 21s to see if I could reliably disassemble and reassemble them and address their tendency to be drippy.

    Another weird thing is that the sac nipples get squishy over time in some of these pens, or at least the two from 1952 whose sacs I planned to replace.

    I attempted repair of one of those pens by cutting off the sac nipple, drilling out the connector, and fabricating a nipple out of Delrin. Below is the section I drilled out and a squishy one.



    I surfaced the Delrin rod, drilled it out, then turned it for the sac nibble diameter and to fit snugly in the connector.





    I used 5 minute epoxy to adhere the replacement nipple in place. Unfortunately I goofed and the connector split at the end. But the epoxy seems to be holding it together.

    I didn't have a small enough boring bar for the connector or I might have avoided this issue that I blame on drilling the flexible connector.

    Here are the two connectors, one with the nipple fitted.



    Here's the new sac in position.



    Once I put things back together using the best parts from two pens, I realized the feed was cracked at the tip. I've broken two feeds already—they seem to be incredibly delicate and brittle.

    Keeping in mind that this was a cheap test pen that would otherwise go in the bin and that repair would require parting out yet another pen, I decided to try reinforcing the cracked area with some CA glue. I didn't think it would stick, let alone strengthen the area. But it did. It also strangely affected the texture of the feed material.

    I put the pen back together and it writes for now. I wouldn't sell or give it to anyone, as I don't really trust it will hold together over time. But we'll see I guess.

    Anyway, I am kind of done with 21s. They're not worth enough to offset how frustrating I find them to work on.

    Thoughts, suggestions, constructive criticism welcome.

  2. The Following 2 Users Say Thank You to azkid For This Useful Post:

    Pterodactylus (September 2nd, 2019), Robert (September 2nd, 2019)

  3. #2
    Senior Member
    Join Date
    Apr 2013
    Location
    SFO USA
    Posts
    993
    Thanks
    11
    Thanked 767 Times in 388 Posts
    Rep Power
    7

    Default Re: Parker 21 repair attempt

    Unfortunately the Mushy Nipple Syndrome can be found on pens across the hooded line in the early 50s models. Some crude analysis suggests a change in materials and/or leaching of plasticizer causing the observed problem. Note worthy is this has been found on new old stoc repair parts so it is not an ink related issue.

    Generally it is not necessary to replace the sac unless one wants the clear experience for a few fills as even though the nipple is mush it almost always remains well attached to the sac.

    I like to use Styrene as the Delrinnis sometimes a bit greasy and doesn’t take will to shellac.

    It is quite Nobel if you to do this to save 21s of any version. I’ve taken to just replacing the whole assembly even on 51s as the number of cores I have for repairs vastly out numbers the nibs and caps that are available to make pens complete.

    It is good practice for section repairs though you would use hard rubber or celluloid as appropriate for standard section pens.

    Well done.

  4. The Following 2 Users Say Thank You to Farmboy For This Useful Post:

    azkid (September 2nd, 2019), Chrissy (September 3rd, 2019)

  5. #3
    Senior Member azkid's Avatar
    Join Date
    Mar 2018
    Location
    Colorado, USA
    Posts
    1,369
    Thanks
    2,325
    Thanked 1,112 Times in 530 Posts
    Rep Power
    3

    Default Re: Parker 21 repair attempt

    Thanks so much for all the info and input.

    I may try to redo this with styrene on the other section just for practice and as a spare if the sac comes off the Delrin. I ordered a smaller boring bar now, too.

    For now I'm out of parts. I wished I had the knowhow and equipment to fabricate a new feed and/or connector... Maybe some day.

  6. #4
    Senior Member
    Join Date
    Apr 2013
    Location
    SFO USA
    Posts
    993
    Thanks
    11
    Thanked 767 Times in 388 Posts
    Rep Power
    7

    Default Re: Parker 21 repair attempt

    You can buy appropriately sized Styrene tube, much easier than making a pipe; drill, glue, cut.

  7. The Following 2 Users Say Thank You to Farmboy For This Useful Post:

    azkid (September 2nd, 2019), Chrissy (September 3rd, 2019)

  8. #5
    FPG Donor ♕ Chrissy's Avatar
    Join Date
    Dec 2013
    Location
    Berkshire UK
    Posts
    5,529
    Thanks
    2,555
    Thanked 4,638 Times in 1,788 Posts
    Rep Power
    12

    Default Re: Parker 21 repair attempt

    Many thanks for that informative post azkid. Good job.

    Many thanks to Farmboy too. Always generous with expertise.

    I'm not even sure I know what a 21 looks like, and must look at some images.....
    Last edited by Chrissy; September 3rd, 2019 at 01:02 AM.
    Regards, Chrissy | My Blog: inkyfountainpens

  9. #6
    Senior Member Robert's Avatar
    Join Date
    Oct 2012
    Location
    Houston, TX
    Posts
    556
    Thanks
    708
    Thanked 303 Times in 220 Posts
    Rep Power
    8

    Default Re: Parker 21 repair attempt

    Very informative post. It makes me more appreciative of my 21 - - which is still going strong.

  10. #7
    FPG Donor ♕
    Join Date
    Feb 2014
    Location
    Sacramento, California
    Posts
    715
    Thanks
    92
    Thanked 462 Times in 175 Posts
    Rep Power
    6

    Default Re: Parker 21 repair attempt

    21's are one pen I stopped working on altogether. Their plastic is too fragile for me to bother with anymore. Even repaired cracks would often crack again which I have never experienced on any other pen. I never saw the squishy sac nipple problem, though.

  11. The Following User Says Thank You to RayCornett For This Useful Post:

    azkid (October 7th, 2019)

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •