i’m thinking about fitting a delta printer with a few of these geared steppers. if you know anyone that has already done this or you have any objects please raise your hand.
Why? They are reduction gears making your movement speed lower… one of the reasons that you choose a delta…
@Camerin_hahn there’re two types of deltas: with and without a linear rail. For deltas with a linear rail, you’re right. For deltas similar to FirePick (http://static1.squarespace.com/static/53c16638e4b0fb85d41808ab/t/547a83afe4b01e4f6559b396/1417315247789/?format=1500w), a small reduction ratio could improve precision, while still maintaining good speed.
I use a geared stepper for the extruder, great for fine control of extrusion and retraction, but never really seemed like the x y and z needed such fine control. Maybe for very small high quality prints it would be useful? One designed to make jewelry blanks fo later casting?
Linear deltabots (at least conventional designs) will be to slow with that kind of gearing, but an angular deltabot should have that type of gearing. Here’s an example of one using that type of motor: http://blog.aaronbot3000.com/p/pythagoras-drawing-delta-robot.html
I would only use one on the extruder. Nema 17’s on the arms even at 250mm/s are not stressed. I even have my 2.5A ones turned down to 1.6A with no problems
ok thank you everyone for your input, i redid my calculations and realized that the res will be high enough for what i’m doing.
That’s a nice looking motor.
Now it could be nice on a 3mm extruder. It would give you much more torque and a small package.
Metal planetary gear set?
Check out this BondTech Extruder: http://youtu.be/18dc96ZMd2I
I use those. Common in many Bowden systems. Makes for a very simple extruder cold-end. See this cold-end, a single printed piece that mounts to your reduced gear drive : http://birenboim.com/tmp/extruder.png It uses a few mounting screws, and one common bearing for tension.
It generally costs around $16 extra to get the reduction gear, then $9ish for a hobbed drive gear to fit the shaft. There are many printed assembly alternatives, often using cheaper parts like a hobbed bolt shaft. Save a little $$, but quite a bit of extra work and construction complexity. It just depends on weather around $20 extra is worth it to you for a more reliable assembly.
One nice thing about printing your extruder gear reduction is that you get more freedom on the gear ratio, but you may find yourself re-printing plastic gears from time to time.
I would avoid these metal reduction gearheads on most direct extruders since they do tend to weigh more. Then again, if space/volume is an issue, these could make a very compact extruder.
I use that same gearhead on a number of my printers, both delta and Cartesian. @Johann_Rocholl designed a bowden extruder body for it as part of his Kossel Mini design. You can find it on github here https://github.com/jcrocholl/kossel
If you are looking for a gearhead to use on a direct mount (non-bowden) system, take a look at the RepRapDiscount BulldogXL - It’s a bit lighter and more compact than this one.