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The Crummy Rubber Feet
on Some HP Calculators

by Joe Horn

Take a good look at the rubber foot on the left side of the bottom of the HP 50g photo above. Unlike nice, new, clean rubber feet, this foot is surrounded by a gross layer of thick goo. The problem is that the feet are glued in place, using a cheap glue that degrades over time due to the warmth of the hand, and skin oils that are rubbed off the palm by the rubber feet. The first thing that happens is that the glue oozes out and around the foot. Then the foot slides out of place, then falls off entirely (see the missing foot on the right side of the photo above).

Even though I personally seem to have industrial-strength skin oil, this problem of crummy HP calculator feet is well known in the HP calculator community. Another HP 50g’s feet are shown above. See the goo? It not only collects dust and dirt and lint and hair and bacteria etc., but it also rubs off onto clothes. Yuck!

Shown above: A close-up of a massively grody HP 50g foot not long before it fell off.

Shown above: Another foot. Is that gangrene or leprosy? This is SO GROSS!!!

It’s not a new problem, but HP never seems to learn. The feet on HP-41’s were notorious for falling off. After my 41’s feet fell off, I replaced them with “rubber bumpers” from the local hardware store. The result can be seen above. These puppies haven’t budged in over 20 years! And they hold the calculator steady on a desk, better than the original feet did.

As you can see above, I performed the same foot-replacement surgery on my HP 50g. I used thinner "rubber bumpers" this time, and the result is excellent.

I must be fair to HP and mention that they had PERFECT feet on their HP 48 line of calculators. Those feet were not held in place by any glue whatsoever. They were almost cubical in shape, and were wedged into a large hole in the calculator case. Friction held the feet in place. They never came out unless purposely pried out with a fingernail, and even if they were removed, they could be pushed back into place easily and securely. A great design, which subsequently was abandoned by HP in favor of gross gooey glue. Go figure.

Disclaimer: I do not work for HP or anybody else.

“Truth is just truth; you can’t have opinions about truth.” -- Peter Schikele

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