Chair Today Gone Tomorrow

When I reconfigured my music room -slash- office a couple years I built a desk in place, in front of the windows, so I have a nice view of the front yard as I work. I put the desk surface on top of two file cabinets, so it's a bit higher (29-1/2") than a normal work surface but I thought I wanted that.  I'm a bit taller than average and always raised my worksurfaces at work to higher than normal.

The past 2-3 years I have had what I diagnosed as a rotator cuff injury in my right shoulder; it hurt to raise my arm above my head.  This made certain sleeping positions uncomfortable, and made swimming painful.

Well, the swim season just started again (June 1) and my shoulder was hurting, so I started mousing left-handed again as I had done at work for the past few years, when carpal tunnel began to affect my right forearm.

After just a few days of left mousing, I noticed that same shoulder pain -- beneath the scapula, in the articular cartilage -- in my LEFT shoulder.  

And it hurt when I used the mouse to scroll (my Magic Mouse doesn't have a wheel, but allows you to use the whole topside as a trackball).

Wow, I thought -- I wonder if my whole problem is ergonomics, and the "rotator cuff" is actually a shoulder-version of carpal tunnel.  My arm position at the desk is just slightly raised from horizontal-to-the-elbow.  I think it's supposed to be justly-slightly-lowered. Since retirement, I've been spending a lot of time on my computer including some pretty repetitive digital soundfile editing (with a lot of scrolling through files).

There's no way to lower the desk, because of the file cabinets.  I didn't think it would be safe to put my chair on a raised platform.  And the chair was already at its maximum height extension.

So... today I started looking into ways raising the chair itself.  The post it sits on is not really editable.  But the casters...

I went looking for casters with longer shanks.  No such luck.  But I found some taller casters that have a threaded rod on top instead of a post.  The rod is 3/8" 16 tpi and smaller than the shank, so I couldn't just screw it into the chairbase (my first thought).  But, I found some 3/8" threaded rod connectors.  Drilled out the base caster holes to 9/16", used a triangle file to notch six notches in the hole, hammered in the hex rod connectors, and screwed the casters into that.  In the first one I did I accidentally drilled through the top of the chair leg, so  thought, okay, that'll add strength, so I inserted a 1-1/2" piece of threaded rod from the top, to secure the rod connector from the top as well, using a fender washer and a locking nut.

It took a couple hours of fiddlin' and fussin' but by dang if it doesn't do exactly what I hoped.  Neato!

The other thing I'm going to do is once again start using my "computer glasses" that I used at work, which focus at about 26", instead of my reading glasses which focus at 18". I noticed I'm leaning in to the screen.

So keep us posted on whether the shoulder pain improves.

My left shoulder started hurting a couple of weeks ago for no apparent reason. Actually, it's sort of in my back, sort of near the shoulder blade (hard to localise). I haven't done anything to it, maybe I slept on it funny. But it's been driving me crazy. I've been downing Advil like they were M&Ms. So earlier this week I thought I'd get a massage, might loosen things up. Bloody Chinese woman. Got fingers like steel claws. I think she made it worse. Oh well.

LOL, well the first problem arose rather quickly -- five pieces of 3/8" threaded rod aren't enough to hold my weight. All five caster shanks began bending within a few minutes.

After pondering this all night this morning I had the solution (I think) -- I straightened out the rod, chased the threads, and threaded on yet another rod connector. This leaves about 3/4" of rod to thread into the chair, which *should* be enough? The 2" that was exposed before is now encased in steel.

We shall see.

LOL again.

Bought a new chair last night, one of the fancy Aeron chairs. My repair job on the old chair is still holding up -- mostly* -- but the replacement casters have an unanticipated side effect. The old original casters were dual plastic casters, while the new ones are single rubber wheels. Because the casters touch the floormat with half the surface area -- one caster instead of two -- they make divots in the floormat and it makes the chair very difficult to slide. It "digs in" to the mat and I cannot scootch it in.



* - besides which, the casters do not point straight down. They're mounted to the chair legs, which come down at an angle from the chair base, so the casters aim inwards just a little. This is why the threaded shanks started to bend. My new improved "steelclad" design isn't bending anymore, but I've heard some ominous cracking noises from the chair base. I think failure is on the horizon!

richard09 wrote:

So keep us posted on whether the shoulder pain improves.

Not yet

NoCoPilot wrote:

Bought a new chair last night, one of the fancy Aeron chairs.

That's what I've been using for several years (since the old chair refused to stay elevated). Great chairs.

I've lusted after one for years -- had one at work and loved it -- but never felt rich enough before to buy one for home.  But my first SS check came Friday, so I'm sittin' pretty

New chair rises up higher than the old one, without having to raise the casters.

And the armrests raise up to just above the desk surface too, giving me a nice downward slope on my arm position. I think this is the solution, finally.