Stirrer for water testing

[lmm1967]

Embarking on a DIY stirrer to make water testing easier and more accurate.

Most parts will be 3d printed. I'll be using the following purchased parts:

Small fan to spin the magnet - https://amzn.to/2QPg8TZ
DC Motor speed controller - https://amzn.to/2QMu0yd
These magnets - https://amzn.to/2RIpdz3
9v battery holder - https://amzn.to/2A6qb1i

I'll be printing the case in a few pieces so it's easier to put together and change out stuff that breaks or doesn't work. I'll be happy to share the stl files for anyone that's interested.

I'll update here with videos as I get the parts printed as well.

So far I have the portion of the case that will house the fan (in red below) and the piece that will hold the vial (in orange below).

I'll link to time-lapse videos of the prints as I get them processed.

 

[caesar]

following

 

[lmm1967]

Printer being used is a Creality CR-10. I use PETG filament, print on a glass bed, bed temp 80c and hot end temp 230c. Glass cleaned between prints with rubbing alcohol. Printer is in an enclosure to keep ambient air temps steady with no breezes or drafts. Ambient temp inside the enclosure averages about 95f.

I use TinkerCad to do designs, Simplify 3D as my slicer and I'm running OctoPrint on a RaspberryPi 3b to run the printer.

Time-lapse videos are taken using an ArduCam Camera (https://amzn.to/2pOsIXR) attached to the print bed with a camera case I designed and printed. The case files can be found here https://www.thingiverse.com/thing:3137311

 

[lmm1967]

Time-lapse of vial holder print.

 

[lmm1967]

Time lapse of Fan Holder portion of stir plate setup.

 

[lmm1967]

Here is the fan cover plus vial holder and fan.
Top picture is with fan inserted as it will be on the completed project

bottom picture is with fan sitting outside.




These pieces sit inside the square hole on the piece below. I can't print it out yet since I have to make holes for the on/off/reverse switch and speed dial that are part of the speed controller, which I won't have in my hands until sometime Sunday.

The part as shown below is upside down since that is how it needs to be oriented in order to print.

 

[picoreefguy]

cool project leo. interested to see how this turns out.

 

[urbanknight]

Sweet! Yes sir....I'd like the stl files please!

 

[lmm1967]

I'll put them up on thingverse and provide a link as soon as I have a functional prototype.

 

[urbanknight]

Cool...Thanks Leo!

 

[lmm1967]

Update: - I haven't forgotten about this - just had some distractions.

So I redesigned the base so it will fit all the parts needed into one piece. Did a partial test print (in other words - I need to fix some stuff) so I could test fit all the parts.

Need to make some minor adjustments - and actually clean the print bed so the print doesn't start lifting.

Overall - the parts should fit together nicely. The motor drive does turn then fan using a 9v battery - not sure if I'll stick with the battery or use a power supply. I'd really like to not have to plug this to keep it as portable as possible.

I am going to need to source a stronger magnet to glue to the top of the fan - I'm probably going to tear apart a spare hard drive I have here and use the magnet from that.

 

[lmm1967]

So - a faulty multi-meter = 2 burned up fans plus 1 toasted motor speed controller.

Also = one very annoyed person creating this who then stumbled upon this.....

https://www.amazon.com/gp/product/B072K24X5P/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

which I bought and have been using. All the pieces and parts were going to work - I just needed to get a strong enough magnet to fit & glue on the fan.

But when I saw that stir plate for $30 while staring at 2 fans and controller in my trash can - I decided to purchase it, drink a few beers and move on.

I have been using the stir plate for about 2 weeks, testing 3 tanks twice a week and I have to say this is a VERY worthy investment. I'll post a quick video and very brief review sometime in the next couple of days.