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• Final Version done!

  Crypto [Neo] • 01/13/2017 at 16:13 • 0 comments

  So I finished up the design, it's a bit bigger than 1.5" if you include the housing :P but I'll give myself that one for making something that honestly is pretty darn awesome if I may say so! I haven't really had time to try to fix my drill charger or go get a new one, but eventually, i'll upload a video of this thing in action. In either case to make the video for this version I'm still going to have to wait for that GM23 motor to get to my house.

  I did do some calculations to determine if this thing will work with the gear box. The drive gear from the motor is 10 teeth, and the drive gear for the pump is 43 teeth, that gives us a 4.3:1 gearing ratio. Under ideal conditions this motor can output 0.48Kgf/Cm which gives us an ideal torque on the pump drive gear of ~2Kgf/Cm. I can run the pump using just my fingers on the drive gear (albeit slowly), so I think that should be enough. If it isn't, the design is easy to upgrade to use the GM2, which outputs an insane 3.5Kgf/Cm giving us an ideal torque of 14Kgf/Cm! That will be overkill but I know it will work.

  I uploaded all the files to Thingiverse as well, check it out and like my project on there :) http://www.thingiverse.com/thing:2012218. Also follow me on twitter! @Neoaikon :D

• WIP Files Uploaded

  Crypto [Neo] • 01/10/2017 at 17:19 • 0 comments

  We've uploaded the two successful versions of the pump for you to download and try out. These don't have any housing or motor mounts so you'll have to add that yourself until I upload the version WITH the housing in the next 48 hours or so. If you have a power drill, you can easily try out the pump, we are going to post a video once we get a new charger for ours because for some reason it just HAD to stop charging my battery for this project XD

• Success! On to testing!

  Crypto [Neo] • 01/08/2017 at 22:07 • 0 comments

  So the print came out really really well, nice tight meshing and the gears want to stay in!

  I'm now printing the same thing again because I had forgotten to add a hole to attach my power drill to the drive gear. This will let me properly test the pumping capabilities before moving onward. I'm about to head out and get some Tygon tubing that I can use to properly test. The PVC lengths I have are only 12" and I can't really reach liquids with it and easily run the pump. So close now! It's almost finished!

  One thing we're probably going to do is as well is add a small hole in the planetary gears for some 2mm steel rods, one thing we can see happening is the gears breaking after prolonged use along the layer lines, the rods will help to distribute the force along the entire length of the gear. Time for some eye candy!

  Dat meshing yo...we just love this image and it really shows the work we put into making these very printable. The angles along the herringbone gears are less than 44 degrees so overhangs won't be an issue. When it reaches the center roller we chamfered up from the gaps so that there will be minimal bridging, as well as at the top where we chamfer the transition back to the top herringbone gear. This results in an print that requires NO supports, a requirement because our goal was to make this something anybody could print with minimal tweaking.

• Successful Prototype

  Crypto [Neo] • 01/08/2017 at 02:42 • 0 comments

  The prototype came out WONDERFUL, we tested it with some of the generic PVC tubing I had lying around, and it was able to actually draw fluid! Although twisting it with your fingers is not easy...; The double herringbone design works extremely well, I tested two different versions, one with a 22.5 degree herringbone and one (pictured above) with a 45 degree herringbone. The 22.5 degree herringbone is easier to print but doesn't provide the same degree of "tightness" that you get with the 45 degree, it's very easy to push the gears out of the 22.5 degree one, whereas the 45 degree one it's nearly impossible. But the 45 degree one has a lot of curling on the top of the gears, and I can't accept that.

  I'll probably do one last iteration of the design before adding in the housing and gears and try 33.75, my idea is that this will give a nice balance between the two. Speaking of the housing and gears, lets take a look at that.

  The housing basically consists of a mounting plate for the GM23 motor, and a couple of gears to drive the pump. The outer gear on the pump will get attached directly to the plate. The large gear is screwed into the pumps drive gear, and then turned by the GM23 motor. This design should be 3D printable on any printer, without supports!

  Once I've verified the design works, the final step will be just adding a small housing on the other side to cover the motor and pump internals, then it'll look nice and snazzy!

• Small Scale Slippage

  Crypto [Neo] • 01/07/2017 at 04:20 • 0 comments

  So one of the problems I've been facing has been the planetary gears slipping out of alignment and popping out of place.

  At this scale there's just not enough contact area between those two places to hold everything in place. It would probably work if it was machined out of metal, but with the inaccuracies inherent with 3D printing it's really no surprise my FDM machine couldn't do this.

  So while this would probably work, I've decided to scale it from 1" up to 1 1/2", additionally we've adopted a "double herringbone" design that should increase the contact area and keep the planetary gears securely in place.

  Once it finishes printing I'll be able to assess how well it works, I actually have forgotten to chamfer the overhang shown in the top set of gearing, but it seems to have came out well regardless! It's fixed in the files but I'm not stopping a 2 2/3 hour print to fix a chamfer that seems to have not been necessary :).

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