I have a Prusa i3 and I’m going through a reconstruction phase. I completely changed the design and now fully reconstructed I ran across a problem with the heat bed attached to the z-axis this configuration seem to have damaged the stepper motors. Does anyone know of a stepper motor that will be powerful enough to handle the strain and drive the heat bed and carriage during prints? The weight of the carriage is approximately 3-5lbs. and I was using the NEMA 17 motor that came stock with the Prusa i3. Below is an image of my current setup.
Any help or Ideas would be great. Thanks Makers!
Brien,
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Do you have any information about the steppers used in your printer? Brand, Type, Amps?
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The type stepper I have came stock with my kit. The only information that I can find on it is NEMA 17 Stepper by Kysan
- 42 mm, Gear Ratio: 5.2:1, 20 mm long, 8 mm Shaft with D Cut, Step Angle: 1.8°
- 1830 mm Wire Connector
- Rated Voltage: 2.6V, Rated Current: 1A
- 2 Phase, Inductance per Phase: 3.2mH, Resistance per Phase 2.6 Ohms
- Holding Torque: 9Kg.cm, Class B Insulation
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haha from i3 to that… totally different. curious, any particular reason why you made the change?
Loods more like a Velleman printer. Should have seen that at my first reply. The holding torque is (google 1A stepper) About 1,2500 to 2000g/cm. Upgrading these steppers might help. The 1,7 wantai holds 4000 g/cm and the 2,5 holds 4800. Look at the electronisch, if the can provider 1,7a to two steppers
Do you have a link, Where you bought this printer.
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I’m not really sure why you think that’s funny… And why you offered no useful information to my question. Though this was an open community where we’ve moved past pointless bullying and posturing. I’m sure you are an awesome engineer so please remember there are people on the other side of these screens.
If you must know spite you complete lack of help… I started this project to explore… “Sound familiar.” You probably had the same passion one day you started. I wanted to improve my design, and eliminate variance by take the print area off the y-axis. Let me know if you have any other questions.
Brien,
Here’s the link where I purchased it. Awesome information. Thank you for helping I really appreciate it!
https://www.3dprintersonlinestore.com/replikeo-prusa-i3-rework-kit
You misunderstood me.
My “haha…” to you was actually a compliment that you went a great length of effort to change what you think could be better. I built myself an i3 so I know it’s limitation and it’s quirk and has been making changes here and there but for the most part stay within the i3 overall design. I never thought about changing it to a core xy type like what you did there.
So I suspect in a way you may have solved a lot of problem I was trying to solve and still am.
Stephen
I also think this is a great mod for a Prusa. And it must have been a lot of work. I’ve made a Prusa I3 using LEGO (http://www.instructables.com/id/LEGO-3d-Printer/), I’ve modified this printer to print chocolate, instead of PLA/ABS.
First things first, are you sure it’s the Nema Steppers? It could be the electronics used for driving the steppers. They stop working when they become too hot (overcurrent protection). Your printer has A4988 stepper drivers. They are rated 1A with no cooling. You have two steppers, 1 Amp each! I would start with adding heat sinks and a forced airflow.
It’s alway possible to buy new Nema steppers, but stronger motors (1.7A) require drv8825 stepper drivers, with heatsink and airflow.
Do all motors work with no load? what happens if you modify the wiring for x,y with z1,z2?
Test your motors one by one, with no load. Next step would be checking the stepper drivers.
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Oh sorry about that. It’s was hard to tell when I read it. I apologise for the aggressiveness. Thanks for the nice words, I’m trying to really dive in and learn this technology. I have a new idea from a design I’m going to work on next. I haven’t drafted it yet. I’ll keep you posted.
Brien,
Yes I’m sure that it is the NEMA. All electronics are brand new, and when I tested motors unattached on z-axis one of them did not move, the other did not move consistently. All other motors work in x,y,z1, and z2. Thanks for letting me know about the stepper drivers requirements.
Thanks for the help,
