Friday, January 11, 2013

Finding Stepper Motors in Printers

So, growing up I always heard that if you want to get cheap stepper motors, gut an old printer or scanner.  [Why, what were you told growing up?]

A printer needs a minimum of 2 motors.  One to move the inkhead back and forth and another to advance the paper.  So, theoretically, you can get 2 small stepper motors for the price of a used inkjet (so free, if you're vigilant on trash day).

Anyway, newer printers have moved away from this and are now using DC motors and an encoder.  So, while this is much cheaper for the manufacturer, it's no good for us.

In any case, just look inside the printer at the ink carrier, that's the little shuttle that carries the ink cartridges.  It will have a toothed belt behind it, and be travelling on a smooth, shiny steel rod.
If you see grayish transparent ribbon running parallel to the rod,that's the encoder.  This setup uses plain dc motors.  If the ink carrier uses an encoder, you can be sure the paper feed does too.  Save your money and look some more.

Don't worry, I tossed the carcasses into the recycling bin afterwards.

Tuesday, January 1, 2013

Bluumax hold-down and surface install

Holy crap, look how well that fits.  I swear I don't plan this stuff...

That platform is supposed to be 16" as per bluumax spec.  Each rail is .75" and the wood things are 4.5"-ish. So 4.5x3 + .75x2 = 13.5+1.5=15... Wut?

Late Christmas

Did a bit of shopping, and checked the mail.

Arduino motor control shield and some chips came in!  Gonna install some T-track rails on the mill and got some sacrificial surface boards.  And finally, Exhaust wraps to insulate my rocket stove.  Exciting stuff!

Monday, December 31, 2012

Exam table refurbishing

So, part of "special projects" at the clinic involves general equipment maintenance.  Examination tables are rather expensive for what they are and so all of the tables here have been bought used.

To clean them up a bit, and have them match the decor, we've set about repainting the drawer panels, and making new ones for the damaged pieces.

Those white pieces are proving especally troublesome because they are plastic.  I had to devote a whole paint-dry cycle (2 days) because we had to prime them with a plastic gripper first.  They won't go on til Thursday.

Mobile App

Just installed the blogger mobile app to my phone.  I've always had trouble with the disconnect between doing something then writing about it later.  Hopefully, this will make actually blogging about my projects possible.