Fixing Damaged Bucking Spring

[SamirD]

I was looking at one of my M's that needs parts and has a broken barrel on the f5 key and I noticed the f12 key looking a bit droopy too.  So I popped the stem and noticed that barrel was cracked too.

When I went to put the stem back it, it got stuck in the depressed position.    I immediately found a way to wedge it back out and took it off to find the end of the spring is bent now (like a ball point pen spring that has been damaged so that the coils are not the same all the way through), like it got stuck in between the stem and the broken part of the barrel (part of the spring was then outside the barrel) so that's why the key got stuck.

I was able to position the spring properly in place and replace the stem, but now that key doesn't click.  I haven't connected it to a computer to see if the key registers, but something innately tells me it doesn't.

Can anything be done to help this spring get back to normal?  Thank you in advance! 

[CPTBadAss]

First of all, how many times have you reseated the cap? Sometimes you have to replace the cap to get the switch to click a few times.

You may have to replace the spring and flippy. I'd suggest trying to epoxy the barrel together as well. But you might have to replace the barrel plate.

[SamirD]

First of all, how many times have you reseated the cap? Sometimes you have to replace the cap to get the switch to click a few times.

You may have to replace the spring and flippy. I'd suggest trying to epoxy the barrel together as well. But you might have to replace the barrel plate.

I've only done it twice since it's very tricky to get the spring properly in the stem since the bottom part of the barrel is cracked off (whoever orginally handled this board obviously had thrown it into the box and the f keys took the brunt of it).  I'll try it again a few times, but doesn't the deformed spring have anything to do with it?

I'm thinking that getting my hands on a bad barrel plate and carving some replacement barrel parts for the broken barrels to glue in place would be a permanent solution.  Or just sending the whole board in to Unicomp to have it repaired.  They will actually reattach the plate like the factory without a bolt mod.

[Snowdog993]

First of all, how many times have you reseated the cap? Sometimes you have to replace the cap to get the switch to click a few times.

You may have to replace the spring and flippy. I'd suggest trying to epoxy the barrel together as well. But you might have to replace the barrel plate.

I've only done it twice since it's very tricky to get the spring properly in the stem since the bottom part of the barrel is cracked off (whoever orginally handled this board obviously had thrown it into the box and the f keys took the brunt of it).  I'll try it again a few times, but doesn't the deformed spring have anything to do with it?

I'm thinking that getting my hands on a bad barrel plate and carving some replacement barrel parts for the broken barrels to glue in place would be a permanent solution.  Or just sending the whole board in to Unicomp to have it repaired.  They will actually reattach the plate like the factory without a bolt mod.

Huh?  I don't comprehend what you are saying at all.  Not enough information?

Edit: I am guessing you have a broken barrel on your F12 key, the key was taken off, and replaced and the spring got hung inside the frame, then you removed it, and it was bent out of shape, and it won't click at all.  The "crack" is vertical or horizontal?  I'm puzzled.

[fohat.digs]

In my experience, a deformed spring is hopelessly dead.

Why go through the agony of trying to cobble together an imperfect fix on a cheap plastic part?

Do a bolt mod and replace the barrel plate and ruined spring/pivot plate assemblies.

If you are interested in Model Ms you will quickly accumulate some parts donor boards, and Unicomp only charges $10 for a barrel plate, as I recall.

[SamirD]

First of all, how many times have you reseated the cap? Sometimes you have to replace the cap to get the switch to click a few times.

You may have to replace the spring and flippy. I'd suggest trying to epoxy the barrel together as well. But you might have to replace the barrel plate.

I've only done it twice since it's very tricky to get the spring properly in the stem since the bottom part of the barrel is cracked off (whoever orginally handled this board obviously had thrown it into the box and the f keys took the brunt of it).  I'll try it again a few times, but doesn't the deformed spring have anything to do with it?

I'm thinking that getting my hands on a bad barrel plate and carving some replacement barrel parts for the broken barrels to glue in place would be a permanent solution.  Or just sending the whole board in to Unicomp to have it repaired.  They will actually reattach the plate like the factory without a bolt mod.

Huh?  I don't comprehend what you are saying at all.  Not enough information?

Edit: I am guessing you have a broken barrel on your F12 key, the key was taken off, and replaced and the spring got hung inside the frame, then you removed it, and it was bent out of shape, and it won't click at all.  The "crack" is vertical or horizontal?  I'm puzzled.

Sorry for the lack of pictures to go with the words.  Great guess as you're pretty much right on except the crack is vertical with the cracked piece missing (imagine a V cut out of the front side of the barrel).  The spring got hung up on this V section and when the stem was placed back in, and it deformed the spring since it was outside the barrel in the V section.  It basically worked like a guillotine, except the top of the spring didn't sheer off, but was deformed.

This help any?

[SamirD]

In my experience, a deformed spring is hopelessly dead.

Why go through the agony of trying to cobble together an imperfect fix on a cheap plastic part?

Do a bolt mod and replace the barrel plate and ruined spring/pivot plate assemblies.

If you are interested in Model Ms you will quickly accumulate some parts donor boards, and Unicomp only charges $10 for a barrel plate, as I recall.

Bummer.

I don't want to go through all the work for repairing the board like that.  If I can bandaid it, it's good enough.  This isn't a daily driver, just one that ended up not being in great shape in my great keyboard purchase back in the day.  I didn't think much of it except when examining it, it's a 1988 white label with the sdl, so a nice board. 

I started looking at all the odds and ends that it needed and it was mainly some missing caps.  f5's barrel is cracked to the point you can really tell, but I was examining the board and noticed f12 being a bit droopy as well.  I should have been more careful putting f12 back together--my own fault.

I'm going to attempt to rebend the spring back into proper shape with some hemostats when I have time and see if that fixes it.  Otherwise, if the key registers, I guess it will just have no click.  Worse comes worse, I'll just sent the whole board to Unicomp for refurbing.  They can actually replace the barrel plate without doing a bolt mod (which has its own issues).  Unicomp redoes the rivets like factory.

[fohat.digs]

Unicomp redoes the rivets like factory.

Unicomp opens the case, removes the guts, and puts in a new set of guts.

You will have a 2015 Unicomp keyboard in a 1988 IBM case.

[Snowdog993]

I have the feeling your barrel frame is really damaged badly.  Not only on the front side, but in the back side too.  You probably lost the rivets holding the top part of the keyboard together.  That explains the "droop" of the key to begin with.  It's probably not clicking because there is not enough tension between the barrel frame and the back plate.
In any case, you can try to band-aid it, and see if that will fix it.  However, you will still have the same problem with the barrel if there is a chunk of it missing.  The hammer behind the F12 key may be out of alignment with the barrel frame, and the membrane may (or may not) be damaged.
It's really a question of what you want to do with it.  I hope you get it working.

[SamirD]

Unicomp redoes the rivets like factory.

Unicomp opens the case, removes the guts, and puts in a new set of guts.

You will have a 2015 Unicomp keyboard in a 1988 IBM case.

Not from what they told me on the phone.  They said they have the barrel plate as a part and can replace mine as part of a repair.  He even mentioned I could do it myself with a bold-mod, but theirs will be sealed the same as factory.

I have the feeling your barrel frame is really damaged badly.  Not only on the front side, but in the back side too.  You probably lost the rivets holding the top part of the keyboard together.  That explains the "droop" of the key to begin with.  It's probably not clicking because there is not enough tension between the barrel frame and the back plate.
In any case, you can try to band-aid it, and see if that will fix it.  However, you will still have the same problem with the barrel if there is a chunk of it missing.  The hammer behind the F12 key may be out of alignment with the barrel frame, and the membrane may (or may not) be damaged.
It's really a question of what you want to do with it.  I hope you get it working.

F12 was clicking fine before I took out the stem to check for a cracked barrel.  It was just my retardedness of not paying enough attention to detail to noticed that the spring would move out of the stem as I placed it back in the barrel. 

I'm not sure how bad the rivets are, but the rest of the board feels great, just like the one I'm typing on now.  I really wish whoever slung that board and had it impact the f-row so hard that it broke barrels would have been more careful.

At some point I plan to open up all my M's, and check them over.  I still haven't fixed the one that has the num/cap/scroll lights not working that I posted on here about a year ago.   Their time will come.  I'll also photograph them all in their full glory, before and after (because the before will look yucky!).

[Snowdog993]

I still haven't fixed the one that has the num/cap/scroll lights not working that I posted on here about a year ago.

That can be fixed.  You may need to bypass the ribbon cable and use an arduino 4-pin M/M cable.  (Or something similiar.)



I guess nobody really looks at my pictures much.

[SamirD]

I still haven't fixed the one that has the num/cap/scroll lights not working that I posted on here about a year ago.

That can be fixed.  You may need to bypass the ribbon cable and use an arduino 4-pin M/M cable.  (Or something similiar.)

Show Image

I guess nobody really looks at my pictures much.

I remember that pic!  :thumb:

I think you posted it in my original help thread.  :cool:

I just haven't had the time.  I think I've only used that keyboard twice for 10s each in the last 5 months.