Saturday at 10BitWorks - - April 1, 2017

[Don Smeller]

It was a slow day at Lake WoBits-r-gone.  Only 14 people.

Charles, of XCSSA, Exotic Computer Systems of San Antonio, brought in the pump portion of his cat’s fountain.  Say what?  Yeah.  Apparently some domestic cats won’t drink water that sits stagnant in a bowl or a puddle.  They drink zilch and get dehydrated and as a result develop maladies of the kidneys and other organs. Veterinarians prescribe cat fountains.  The movement tricks Fluffy into thinking the water is fresh.  Voila.  She drinks.  But, there’s always a but.  The fountain model that Charles purchased (see image) makes too much splashing noise.  His mission, to quiet it down. Being of a mechanical bent, I suggested stainless steel wool at the point of impingement.  But Charles, being of an electronics bent, and a born hacker,  was into slowing the flow rate by fiddling with the voltage.  If it were a d.c, motor its speed would be fairly linearly proportional to the applied voltage.  But this was an a.c. motor.  It didn't run at all until it got to about 85% of full voltage, and then the flow was practically full flow, and noisy.  Hmmm 

  

Alexander attended Lee High School attracted there by a magnet program that teaches printmaking and other art related crafts.  Now he’s a college student and he’s trying to earn a buck in the art world.  He’s been commissioned to make 26 participation trophies for a garden club.  The goal is to put text, with a prescribed font, around the conical outsides of certain given terra cotta flower pots (see image).  He was thinking of laser cutting a stencil.  But that wasn’t work because the font is not a stencil font (see image). He considered engraving the letters into acrylic to make a mold and then pouring silicone into the mold to make a stamp, backward of course. But that seemed like a long way to Tipperary. Alas, he hit on the idea of making 2 stamps by engraving away the negative space of rubbery bendable linoleum blocks to leave standing letters. Backward of course.  Saturday he made the lower of the two stamps.  Note that the upper line of text has a slight frown that compensates for the smile that results when a straight ribbon is wrapped around a cone.  

 

Don S

[Randy Ohman]

I know just enough to be dangerous...but for a low watt motor like this he might try an incandescent light dimmer switch:

http://www.factsfacts.com/MyHomeRepair/DimmerSwitch.htm

On Sunday, April 2, 2017 at 5:13:34 AM UTC-5, Don Smeller wrote:

It was a slow day at Lake WoBits-r-gone.  Only 14 people.

Charles, of XCSSA, Exotic Computer Systems of San Antonio, brought in the pump portion of his cat’s fountain. The fountain model that Charles purchased (see image) makes too much splashing noise.  His mission, to quiet it down, slowing the flow rate by fiddling with the voltage.  If it were a d.c, motor its speed would be fairly linearly proportional to the applied voltage.  But this was an a.c. motor.  It didn't run at all until it got to about 85% of full voltage, and then the flow was practically full flow, and noisy.  Hmmm 

[Randy Ohman]

Look at the comment section of this page:

http://www.homemade-circuits.com/2012/04/how-to-use-triacs-for-inductive-loads.html