2018-07-30

Solving Problems with a 3D Printer

Solving Problems with a 3D Printer

A couple of years ago I purchased a 3D printer (Lulzbot Mini) to allow me to develop and produce a violin shoulder rest. Here is the second generation - I think it's great. See www.vsr.ravitz.us for more information. In addition to its primary usage, the printer has helped me solve some of the world's biggest problems. Here are four of the most important solutions.


Of course you need a 3D printer to implement these solutions - they can be purchased for a few hundred dollars or, I'm told, libraries have them. And you've got be able to design useful parts - I use a free program call OpenSCAD but you have to design the parts via programming language rather than visually.


Button Magnet

I like to use a magnet to hold my name tag button to my shirt at dances - easy to move, no holes in my shirt. I don't like using a single magnet that has a widely dispersed magnetic field and is difficult to remove (I keep short fingernails to make playing the fiddle easier). So I obtained 3/8 diameter by 1/8 height magnets and 1 inch steel washers (I could not find magnetic stainless steel washers). The magnets sit on the washer, separated slightly, with one oriented north up and the other south up. The shape makes it easy to remove. The button, washer, and magnet orientation encloses the magnetic field for a very strong bond and greatly reduced stray field. This works very well, but -

The early versions required glue to keep the magnets in place and the washers rusted. When I got the 3D printer, I designed a snap together case that holds the magnets in place without glue and prevents washer corrosion. Problems solved.




Heel Wedges

The white heel wedge in the photo is a four degree lateral wedge that helps rotate your ankles slightly, improving your step. I like this - I don't know how many others it would help.

But the wedge won't stay in place. I found a flexible, but not spongy, filament (the plastic that the printer prints with) and designed a wedge with a rim that holds it where it belongs.




Automobile Phone Holder

A good phone holder for your automobile is really useful, especially with navigator apps. But finding a good phone holder for my car was not easy. There is the questionable attachment to the car. Suction cups inevitably fall off and mounting on the windshield blocks vision. Vent vane attachments block ventilation and heat the phone when the heater is running. Cup holder mounts use up a cup holder. And there is the questionable attachment to the phone as the holders need to work with many different phone sizes.

I bought one of the cup holder devices - my car has four front cup holders so it seemed reasonable. The cup holder attachment worked well. But the phone holder was hopeless.

I designed a simple drop-in box and added leather padding (I had sticky back leather from experiments with dance shoe soles. It's handy for other things too.) It's easy to drop the phone in and take it out, with or without the charging plug. It holds the phone securely as long as the car doesn't roll over. I can press the on/off, volume, and fingerprint controls easily (only the bottom third of the phone is inside the box). Of course it only works for a small range of phone sizes, but I can print a new one if I get a new phone.




Pocket Watch

I don't like having a watch on my wrist. And pocket watches are inexplicably large. But it's easy enough to take the band off of a wristwatch and keep it in your pocket. Except that digital watches have buttons that are easily accidentally pressed by stresses in pockets. I used a nice model of watch with recessed buttons for many years. But it is no longer available.

I found a nice digital watch and designed a holder for it that protects the buttons from accidental presses. It makes the watch larger than it should be, but it works well.



2018-07-08

Miscellaneous Thoughts

Miscellaneous Thoughts

Galaxy S9 vs. Pixel 2: Which Android phone should you buy?

This is about a published comparison of two phones -

"Galaxy S9 vs. Pixel 2: Which Android phone should you buy?
...
the Pixel 2 doesn't look sleek.
...
Its (Pixel 2) thick bezels and the matte finish on the (aluminum) back feel dated and cheap, especially in contrast to the Galaxy S9's edge-to-edge curved screen and glossy (albeit fingerprint-collecting) glass casing."

The matte finish aluminum (Pixel 2) is easy to hold, does not show fingerprints, and does not crack when dropped (although the paint is readily scratched down to the aluminum). The glass back (S9) is slick and easy to drop, shows a mess of greasy fingerprints after a little usage, and cracks easily when dropped (despite its being made of Gorilla Glass). And the reviewer prefers the glass.

And of course Google wanted to add some class to the Pixel so they added an easily cracked glass area to the back, encompassing the top two corners to break the fall when dropped.

What's wrong with plastic?

Why does the reviewer prefer sleek to sturdy? Is there some need for good aerodynamics in a phone?


Ad Nauseum

Q*** electric toothbrushes has one ad on the radio. Not too offensive the first five times that you hear it. It repeats about four times per hour, whenever I am listening. If they can't afford to make another ad, how about just running it through a frequency shifter to make different versions. How about just having different people read the script? Of course the script is meant to be read by the inventor, but that doesn't stop KFC from having multiple people play Colonel Sanders in their ads.

I finally resorted to turning off the radio when the ad starts.


More Mind Numbing Radio Ads - Distilled

For all of the following ads - "Alexa pause" (I listen to the radio on an Alexa device because I don't get good radio reception at home).

"I'm an idiot and I can adopt kids" (to paraphrase).

Why doesn't my baby smile? (Autism if you haven't heard.)

"I haven't been sick since I've been on Texas Superfoods." Well how long is that - one week?

"My dog looked and smelled like he had been dead for six months, but these vitamins fixed him right up" (to paraphrase).

Stifel stock market reports - death by numbing the brain.


Verizon Wireless

I purchased Google wireless earbuds at Verizon a while ago. They were useless. Verizon traded them for Apple Airpods (no additional cost). One of the earpieces wouldn't charge. I couldn't tell if it was the case or earpiece. Verizon replaced everything. The new hardware works great. Thank you Verizon.