capacitive or inductive proximity

halo.

I want to ask which is better capacitive or inductive proximity for use in the auto leveling bed?

I went through them all: IR, modulated IR, ultrasonic, capacitive, inductive, and finally differential modulated IR. Capacitive and inductive can both be made to work quite well if you print on a metal bed, although capacitive tends to be sensitive to temperature and humidity. If you use a glass bed, then many inductive sensors won't work at all unless you have a steel plate under the glass. Capacitive sensors are still usable with a glass bed, subject to temperature and moisture sensitivity. Also if you use interchangeable glass beds as I do, they need to have exactly the same thickness and surface coating if any, otherwise the height will depend on which glass bed you use.

Remember that the low cost proximity sensors you can buy are intended to detect if an object is there or not, not to provide a stable distance reference reprodicible to a few hundredths of a mm.

I settled on differential modulated IR because it provides a height reference from the top surface of the glass and works with most print surfaces, with the caveat that when used with plain glass, it doesn't like a strongly reflecting surface under the glass. I am about to put these sensors into mass production. See [forums.reprap.org] for more.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

may for the time being I would choose to use inductive proximity, because it is not affected by temperature and humidity conditions. it would be better to save costs in making my first 3D printer.

I want to ask again. What if I use the bed only aluminum plate without giving heat-resistant masking tape. if it does nothing when printing?

[www.amazon.com]

i use this one, consistent with heat and moisture (live in FL) and it runs on 5v so no weird stepdown voltage divider sass

hi greggo.

Which sensor is your favorite. capastive proximity, inductive or infrared?

neither, i find using a dial indicator and manually leveling the bed just better.