Nema 17 no encoders?


#1

Can I use Nema 17 only, or do I need encoders too?

Thanks a lot


#2

You can use just motors, though you will not have stall detection without them. If you forego encoders, you should look at adding endstops so you can at least do calibration.


#3

Is there any specification about which end stops should be mounted.


#4

I used magnetic proximity sensors which are widely used in industry for this type of function; the sensor is https://www.digikey.com/products/en?keywords=59145-010 and the matching magnet is https://www.digikey.com/products/en/sensors-transducers/magnets-sensor-matched/566?k=57145-000.
You’ll need to work out how to mount them, here’s a picture of one of mine:


Encoder scaling factor
End-stops vs Encoders
#5

You could stick the magnet on with double sided tape, Id also include a hard stop


#6

May I use mechanical end stop? Do I have to change the firmware?

Thanks


#7

Yes, I am also using mechanical endstops and it works fine. You don’t need to change anything in the firmware or anything. Simply mount them, connect them and enable them on the website under hardware settings.


#8

@chrisb Thanks for the info about this magnetic endstop :slight_smile:
I’ve just found (i think) the same ones in my country :stuck_out_tongue:


Last question, how did you connect them to the RAMPS controller?

I’ve found a picture on the forum, but there is no “official” info how to connect endstops to RAMPS/RPi…


End-stops vs Encoders
#9

In general there is no official information how to connect because those endstops are not necessarily needed. Maybe it would fit into the “Mods/Add-Ons” section.

So I edited this picture to show how the connection is working (at least for me). I’m only using those endstops for X and Y axis.


#10

@Loveny I’m trying to enable my magnetic endstops, just the same way you did yours.
I’m having trouble though, when I enable the endstops FB does nothing and stops moving across the selected axis.
Did you made any customization in your build or was it just pling-n-play?


#11

No modifications, just plug them in. Pretty sure they need to be wired so that they switch the ‘signal’ to 5V. They work fine for homeing, but I found them a bit hit and miss in normal operation. Obviously, they need to be enabled on your farmbot.io page too.


#12

Hi, do you have a schematc or detail picture there shows the phisical connection of the magnetic proximity sensors with the farmduino board?


#13

Hi, do you have a schematic or detail picture there shows the physical connection of the magnetic proximity sensors with the farmduino board?