IBM Model M right shift key sticks

[systemparadox]

Hi. I've been using my trusty Model M for many years now.

Recently the right shift key has started sticking - as in, it physically stays stuck down, or is just sluggish to spring back up.

I have fairly small hands so I'm usually pressing on the left 1/4 of the key, and I tend to slide my finger to the left as I press it, which causes the key to tilt slightly.

My suspicion is that it's an issue with the circular support post, but cleaning it hasn't helped at all. I've even tried lubricating it, which has helped a bit, but it's still sticking.

I'm wondering if anyone has experienced a similar issue? Any tips what the problem actually is, and how I might solve it?

Thanks.

[pixelpusher]

Did you try blowing air down into the barrel? Or fiddling with the spring?  Maybe the flapper isn’t set correctly.  I haven’t done a lot of model m repair but when my switches have issues those two things often help.

[systemparadox]

I already tried blowing air in but that didn't help at all. I'm not sure what you mean by "flapper"?

The oil I added was a bit thin so I decided to try some vaseline. I also added some to the normal clip post. It's much better now, although still not perfect. I guess I will have to open it up and have a look at the spring.

[pixelpusher]

Vaseline is a petroleum product and will degrade the plastic over time.  You should clean it out and use dielectric grease instead.   Superlube is a good solution for Vaseline like texture that is safe for plastic. 

Someone had a similar issue in another post recently and another member suggested that it could be broken rivets.

As you may know, the model M has the plate and pcb riveted together with plastic pieces.  If enough of them have broken (which happens with age), it could be causing the problem.  You should be able to tell by taking the cover of the case apart and looking at the plastic rivets on the back.  It’s faitly easy to fix if that is the issue

Look for model M rivet repair.  You’ll have to drill through the remains of the original plastic rivet and insert a screw.

Just something to check for. 

[daskeybo]

Hi. I've been using my trusty Model M for many years now.

Recently the right shift key has started sticking - as in, it physically stays stuck down, or is just sluggish to spring back up.

I have fairly small hands so I'm usually pressing on the left 1/4 of the key, and I tend to slide my finger to the left as I press it, which causes the key to tilt slightly.

My suspicion is that it's an issue with the circular support post, but cleaning it hasn't helped at all. I've even tried lubricating it, which has helped a bit, but it's still sticking.

I'm wondering if anyone has experienced a similar issue? Any tips what the problem actually is, and how I might solve it?

Thanks.

Some support posts are off Center.  Try filing the hole.

[ander]

The oil I added was a bit thin so I decided to try some vaseline. I also added some to the normal clip post...

Yikes, dude! That stuff reacts with plastic. Wipe it off immediately.

I use this Inox MX3 lubricant. It's non-reactive, non-corrosive, works great. I just spray a bit in the cap, then use a Q-Tip to wipe some around the key stem and the inside of the spring barrel. And because it's so pure (it can even be used around food production), it's good for all kinds of other things around the house, too.

[rich1051414]

Also, you said right shift? That key is stabilized right? Does it have the barrel inserts? You may want to fiddle with it a bit. Here is another thread on this: https://geekhack.org/index.php?topic=68042.0

[rowdy]

For reference: barrel inserts

I had one that was sticking like this, and I remove the key, inserted a screwdriver and wiggled the insert around a bit.  After replacing the key it was no longer sticking.