Author Topic: Fixing/Replacing Broken Model F Mechanism  (Read 1996 times)

0 Members and 1 Guest are viewing this topic.

Offline handystack

  • Thread Starter
  • Posts: 27
  • Location: United States
Fixing/Replacing Broken Model F Mechanism
« on: Fri, 07 February 2014, 12:17:39 »
So I pulled the spacebar off an IBM model F PC/XT (any story that begins this way is not going to end well).  When I was reassembling the keyboard after hooking the stabilizer back onto the spacebar, I must have unseated one of the buckling mechanisms, which was broken while I hammered the the keyboard assembly back together.  Is there anywhere that I can get a spare part or can someone advise me on a good epoxy to mend the thing?  here are some pictures: http://imgur.com/a/bknWG
As you can see, these are not the same as model M buckling spring mechanisms.  I tried using plastic cement on it, but it sheds that stuff like water off a duck's back.

Offline fohat.digs

  • * Elevated Elder
  • Posts: 6533
  • Location: 35°55'N, 83°53'W
  • weird funny old guy
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #1 on: Fri, 07 February 2014, 16:07:14 »
ygpm
From the US Constitution, Article 1, Section 8 :

The   Congress   shall have Power
To declare War,  grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;
To provide for calling forth the Militia  to execute the Laws of the Union, suppress Insurrections and repel Invasions;

Offline berserkfan

  • Posts: 2135
  • Location: Not CONUS Not CONUS Not CONUS Not CONUS
  • changing diapers is more fun than model f assembly
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #2 on: Sat, 08 February 2014, 13:32:06 »
So I pulled the spacebar off an IBM model F PC/XT (any story that begins this way is not going to end well).  When I was reassembling the keyboard after hooking the stabilizer back onto the spacebar, I must have unseated one of the buckling mechanisms, which was broken while I hammered the the keyboard assembly back together.  Is there anywhere that I can get a spare part or can someone advise me on a good epoxy to mend the thing?  here are some pictures: http://imgur.com/a/bknWG
As you can see, these are not the same as model M buckling spring mechanisms.  I tried using plastic cement on it, but it sheds that stuff like water off a duck's back.

you sound like me.

I break things like nobody's business. Especially old vintage keyboards that cost me hundreds of dollars to buy and import to my country.

that said, anybody who pulls the space bar off his F XT is asking to be F--ed
Most of the modding can be done on your own once you break through the psychological barriers.

Offline fohat.digs

  • * Elevated Elder
  • Posts: 6533
  • Location: 35°55'N, 83°53'W
  • weird funny old guy
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #3 on: Sat, 08 February 2014, 14:17:28 »
get a spare part

Did you get my private message?

When I re-assemble those spacebars, I use a weight on a loop of thread to hold the parts down, then pull the thread out when it is together. Something like a screwdriver hanging off the edge of the table works well.
From the US Constitution, Article 1, Section 8 :

The   Congress   shall have Power
To declare War,  grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;
To provide for calling forth the Militia  to execute the Laws of the Union, suppress Insurrections and repel Invasions;

Offline handystack

  • Thread Starter
  • Posts: 27
  • Location: United States
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #4 on: Sat, 08 February 2014, 18:14:11 »
Yeah model Fs should come with a DO NOT REMOVE SPACEBAR warning label.

Thanks foghat I did get your message. I'm glad that somebody has spare parts for these things. I really do want all the keys working partially because of the sentimental value the keyboard holds for me.  It came with my dad's first computer and I am fixing it up for my brother to type his novel on instead of his terrible laptop keyboard.

To reassemble the keyboard I have to hold the plates together and mate the metal slots by bracing one plate against my desk and pounding the other with a hammer. I feel like I am asking for trouble every time I do this. Is there really no better way?

Offline Soarer

  • * Elevated Elder
  • Posts: 1918
  • Location: UK
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #5 on: Sat, 08 February 2014, 18:26:18 »
There's a mounting hole at the end of the backplate that you can use to lever the two together with a screwdriver. It can still take a hammer to get them fully home, but by then everything is held OK.

Offline fohat.digs

  • * Elevated Elder
  • Posts: 6533
  • Location: 35°55'N, 83°53'W
  • weird funny old guy
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #6 on: Sat, 08 February 2014, 18:30:47 »
Is there really no better way?

Look at my guide which is for the bigger one, but the principles are the same:

http://geekhack.org/index.php?topic=48786.msg1048948#msg1048948

If you can spend a few dollars on some clamps it can be a big help.
From the US Constitution, Article 1, Section 8 :

The   Congress   shall have Power
To declare War,  grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;
To provide for calling forth the Militia  to execute the Laws of the Union, suppress Insurrections and repel Invasions;

Offline ninjadoc

  • Posts: 569
  • Location: Cincinnati, OH
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #7 on: Sun, 09 February 2014, 10:12:26 »
So I pulled the spacebar off an IBM model F PC/XT (any story that begins this way is not going to end well).  When I was reassembling the keyboard after hooking the stabilizer back onto the spacebar, I must have unseated one of the buckling mechanisms, which was broken while I hammered the the keyboard assembly back together.  Is there anywhere that I can get a spare part or can someone advise me on a good epoxy to mend the thing?  here are some pictures: http://imgur.com/a/bknWG
As you can see, these are not the same as model M buckling spring mechanisms.  I tried using plastic cement on it, but it sheds that stuff like water off a duck's back.

So what usually breaks when you pull off the spacebar? Everyone says don't remove the spacebar because it breaks something on a Model F but no one ever says what breaks?!

Offline fohat.digs

  • * Elevated Elder
  • Posts: 6533
  • Location: 35°55'N, 83°53'W
  • weird funny old guy
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #8 on: Sun, 09 February 2014, 10:58:23 »
Everyone says don't remove the spacebar because it breaks something on a Model F but no one ever says what breaks?!

I have never broken one, but it is a monumental PITA to get back together because there is an entire "under-carriage" assembly that goes on the back side of the plate. All the pieces have to be in place as you snap it back in place.

I found that using a weighted thread (such as a screwdriver on a loop of thread hanging over the edge of the table) to hold down some pieces while I use my hands on others works well enough. I have not done one of these in at least 2-3 years, so I don't remember the particulars.

From the US Constitution, Article 1, Section 8 :

The   Congress   shall have Power
To declare War,  grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;
To provide for calling forth the Militia  to execute the Laws of the Union, suppress Insurrections and repel Invasions;

Offline handystack

  • Thread Starter
  • Posts: 27
  • Location: United States
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #9 on: Thu, 13 February 2014, 13:33:20 »
Thanks guys!  I finished my project yesterday, and the keyboard works perfectly now.

Thanks to foghat.digs and soarer for the parts and code respectively.  It even has a little bling on it :)
My brother loves it.

Offline jacobolus

  • Posts: 3670
  • Location: San Francisco, CA
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #10 on: Thu, 13 February 2014, 19:03:11 »
It’s not *that* hard to get back together. You just have to be careful, because there are all those little fiddly plastic pieces.

Offline fohat.digs

  • * Elevated Elder
  • Posts: 6533
  • Location: 35°55'N, 83°53'W
  • weird funny old guy
Re: Fixing/Replacing Broken Model F Mechanism
« Reply #11 on: Thu, 13 February 2014, 19:52:32 »
It’s not *that* hard to get back together. You just have to be careful, because there are all those little fiddly plastic pieces.

The small ones are not too bad. I had done each type several times by hand before I ever got the 122-key version.

For those, you really need clamps.
From the US Constitution, Article 1, Section 8 :

The   Congress   shall have Power
To declare War,  grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;
To provide for calling forth the Militia  to execute the Laws of the Union, suppress Insurrections and repel Invasions;