What Have You Been Hacking/Making [2018-01-22 edition]

[remmin...@2xlnetworks.net]

This is a message from reMMinderbot.

Makers! It's time to share... what have you been hacking on or making?

Reply to this email with a brief run-down of whatever projects have
been keeping you busy, either at the space or elsewhere. And, include
a photo if you can!


reMMinderbot thanks you!

[the_digital_dentist]

I've been sitting with my feet up for two weeks now and working on my Fusion360-fu.  It's starting to sink in.

The other thing I've been doing is some print cooling fan tests for 3D printers.

About 2 years ago I wanted to make a toy for my cats.  The plan was to levitate a ping pong ball on a column of air, and then shine a laser on the ball from within the air duct.  The brightly lit ball would bounce around in the air and look pretty neat, I think, and would have certainly entertained the cat.  So I printed a conical duct for a 5" axial fan, clamped the duct onto the fan, put a ping pong ball on the exit of the duct and powered it up.  Absolutely nothing happened.  The ball just lifted about a hair (literally) and spun slowly.  When I removed the ball, I could barely feel any air moving.  That got me thinking about all those ducted axial fans for print cooling that litter thingiverse and youmagine.  

Soon after that, looking to continue that project, I picked up a CPAP blower from American Science and Surplus, hooked up an ESC and a servo tester and levitated a ping pong ball.  The problem is it sounded like a leaf blower.  

https://vimeo.com/134684728

Ugh!  I shelved that project for a while, but then thought I could maybe apply the CPAP blower as a print cooling fan on a 3D printer.  They move lots of air through long tubes and do it quietly (when you're not trying to levitate a ping pong ball).  I also made an attempt to use it as a print cooling fan for the chocolate printer (remember that?).

Anyway, I was sitting around without nothing in particular to do, so I thought I'd try to recreate the initial experiment with the axial fan.  I printed a duct and shot a video:

https://vimeo.com/252601428

I posted that on reddit suggesting that people think about it when they are getting ready to design or print a duct for a print cooling fan- no air means no cooling.  I immediately got accused of fakery, so I shot another video:

https://vimeo.com/252609601

I don't know how to explain it.  But it is pretty unexpected behavior.

[Pete Prodoehl]

Mark,

I've been contacted by one person who was sad to see you leave reddit
over this. He said he really valued your posts and wants to see you back!


Pete

> --

[the_digital_dentist]

Too big a waste of time.  Point them at my blog.