Saturday, February 16, 2013

Fun With Metal

You have probably noticed that I have been posting relatively little here of late.  There are several reasons:

1. I have been trying to get my wrist problems to go away. That means minimal typing. I do enough of it at work, and the programs that I use at work are really not suited to using voice recognition software like Dragon Naturally Speaking. I cannot claim to be terribly surprised by this; Dragon has a lot of support for many common business applications, but debugging tools and database management development products are not high runners in frequency of use.

2. What little time I spend on the computer, I tend to spend doing things that can be done with Dragon, such as writing articles for PJMedia, or writing a science fiction novel.  There is not a lot of time left for blogging.

3. I have been getting a small number of orders to ScopeRoller, and I have been filling those as quick as I can. Astonishingly enough, work in the shop does not seem to cause me any wrist problems, probably because I'm not sitting in front of a keyboard.

One customer has a type of mount called a DiscMount.  This is apparently a very popular new design, and he wanted castors for it. This was interesting design problem, because the legs are wood, rectangular, and apparently a rather nice piece of finished wood at that. Ordinarily I would solve this problem by looking for a rectangular aluminum tube just a little larger than the leg, but the legs are actually a slightly oddball size (at least, relative to the standard sizes of rectangular aluminum tube out there).

I came up with a pretty clever solution I think, and I am getting ready to ship it to the customer this week.


The problem was that the standard sizes of rectangular aluminum tubing were either too narrow or too tall, so I put spacers on the inside to being too wide, and then used a sheet of aluminum to correct for being too tall. The sheet of aluminum is clamped down to the leg by bolts, thus distributing the load over 6 in.². As long as the customer uses reasonable force in tightening down the bolts, it will not mar the legs. At the same time, the level of force required is really not all that much: these are primarily held onto the legs by gravity, and clamping force is only if the user lifts this off the ground.

These are made almost entirely of aluminum, with steel for the screws, and a piece of acetal into which the casters are threaded. I'm very tempted to switch from acetal to aluminum, even though it is more work to cut and machine, because aluminum is much less expensive, and all the scrap can be recycled.

For some reason, when I took the picture above, I found myself thinking of some sort of mechanized alien life form. For those of you who saw the film Short Circuit, my wife immediately thought that these must be the children of Number Five.

1 comment:

Larry Sheldon said...

Two quick suggestions--I won't look for discussion.

I was diagnosed with Carpal Tunnel Syndrome back when CTS was the malady de die,

There were things about the specifics of my discomforts that didn't fit, I thought, so I declined the surgery.

I did get sent to a Physical Therapist that taught me some posture hygiene that help immensely (which I think the machine shop does not hurt you--different postures and stresses). (I am convinced that the keyboard is largely innocent--it is the mouse and related small motor movements and tensions that are the killers.)

This is a good point to point out that I am not licensed to give advice in any field.

As time went on the pain expanded to include all of the yoke that extends from one set of finger tips to the other.

Long story short, lots of things to try to get relief for debilitating pain that had centered in my shoulders.

Members of my family prevailed upon me to try a Chiropractor, and against my better judgement, I did.

He forecast a period when things would get worst and they did, but after a week or so, they got better.

I am careful to ignore the posters, TVs, and much of what he says.

But what he does is make me for a couple of months now, as pain-free as I have been in thirty years.