Optical homing and limit switches

Has anyone used these PiBot Optical Endstop Rev1.6 (High Precision Limit Switch)

The price on that website is $2.29 per switch +$1.50 for the cable

This looks like the perfect optical switch at a very low price. I am sure there must be some reason why it won’t work.

I ordered a set of them (the site forces you to pay with PayPal) and they should arrive in about 10 to 15 days so I will post back if they seem reasonable.

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Sounds very interesting, but this part in the item description really peaked my interest:
Used to find the datum point( such as x y z (0,0,0)) or keep movement in intended range.”

Optical sensors are not recommended on CNC due to the contamination issue with the sensor. Chances of debris interfering with the sensor are very high. If you look at their site, they have mechanical switches for their CNC offering.
Look at this thread on Prox Sensors for an alternative to mechanical switches Alternatives to Limit Switches

I have been using them as HOMING sensors with no issues.
When I implemented my machine, I had several optical limit switches available to me (free!).
With that said, I would gladly switch to Hall Effect sensors in the future if I have issues.
They use the same theory and wiring.
So advice to anyone thinking about upgrading (or even starting with) from mechanical:
Route at least 3 wires to your sensors / switches; power, signal, ground.
Then you can pick either technology with little growing pain.

I have 3 Inductive proximity sensor NPN type, trying to figure out how to wire them to xcarve for a while now.

send me the data sheet and I can figure out how to wire them.

The issue i would see with optical switches is dust and debris… This could cause them to stop working, work sporadically, or create false triggers…

you do not want to use optical switches as they will have issues. I have seen 3d printers with these and the dev guy that designed the one I have said that they fail too often.
Inductive would work well if the sensitive is stable. You can use hall effect transistors as well. Just have to set it up correctly. Also be aware if you do go with the hall effect transistors that there are 3 different types. let me know if you do and I an help you get the right ones.

SN04-P2

ftp://ftp.unicauca.edu.co/Facultades/FIET/DEIC/Materias/Instrumentacion%20Industrial/Instrument_Engineers__Handbook_-_Process_Measurement_and_Analysis/Instrument%20Engineers'%20Handbook%20-%20Process%20Measurement%20and%20Analysis/1083ch7_14.pdf

enjoy!