#Piezo sensor software
#Piezo sensor plus

To use rods/pins between the upper part and clamp to reduce lateral movement in the assembly which also causes “wobbly nozzle”, which is detrimental to high quality printing.To cut a hole in the center of the piezo disc through which the filament within a PTFE guide tube (or Bowden tube) passes.The upper part has a recess to center the piezo disc. Between the clamp which has a narrow flange on the top and the upper part (which can be integrated into an effector or carriage) is a piezo transducer, element or disc designed to be a buzzer, these are very low cost $0.50 approximately.

#Piezo sensor plus

The printed parts required for this version and links to several other versions, plus practical assembly instructions are available here: īasic schematic of Piezo Hotend Z-probeA hot end clamp securely holds the hotend.

Practically this works the same as the hotend probe but requires greater complexity in mounting the bed so that it is stable and the piezo discs are sensitive to the heat of a heated bed. In this system 3 piezo discs are used with specially designed mounts below 3 fixing points on which the printbed is suspended. This system is the forerunner of the piezo hotend probe. Whilst this eliminates the issues with mounting the bed, getting a firm nozzle and still having enough compliance to trigger the sensor is the challenge. FSR's in the hotend, a system exists to place FSR's above the hotend.The FSR's are sensitive to high temperatures which necessitates insulation to be used which introduces further compliance. This introduces compliance in the bed, and sometimes even, a loose print bed. Whilst this system works and is comparable in many ways to the piezo hotend sensor, it suffers from the need to suspend the bed on mounts containing the FSR's. Force Sensitive Resistors – placed under the bed.Other z-probe modalities using pressure sensing have been used: Physical touch by the nozzle is thickness independent, and surface material independent (unless theoretically the surface is extremely soft, however the system works on painters tape and hard surfaces equally well). Being able to quickly remove and attach various beds/surfaces is desirable without having to undergo complex or time consuming re-calibration. Surfaces in use in 3D printing vary widely, making some probing technologies less effective, thick glass prevents inductive sensors from detecting the metal beneath, IR reflectivity variation results in error using IR sensors, spray coatings are especially problematic due to uneveness.Z offset can be 0 but practically a small offset of around 0.1mm takes into account the upward movement of the nozzle (and hotend) which is required to trigger the probe. With the piezo hotend probe x and y offset is always 0.

#Piezo sensor software

This can be compensated for in software, and can be minimised by good mechanical build and optimal mounting of hotend and probe, but it does cause problems and compensation in software manually requires time. On a delta, effector-tilt an inevitable consequence of mechanical imperfection, means that an offset probe is either fractionally closer to the bed relative to the nozzle or further away depending on the x,y coordinate. At certain nozzle coordinates the probe is out of the bed due to its x/y offset and cannot probe unless the frame/axes are much larger than the printbed, which is unusual. On a cartesian/corexy machine there is a often a limit to the bed area that can be reached by the probe for the purposes of bed levelling/compensation. Other common probes such as an IR probe, inductive probe, capacitive probe and deployable/servo probes are physically not using the nozzle as the probe, and therefore have offsets in x,y and z.

Having no probe offset from the nozzle.

Being able to determine by probing directly where the bed and this point intersect is theoretically the most accurate method of calibrating/levelling/z-homing, although few modalities so far have achieved this in practice.

The nozzle in a 3D printer is the tool, and the nozzle tip is the point in space that the coordinate system describes.

Most of these aims are self-explanatory but the advantage of using the nozzle as a probe should be explained:

Is permanently mounted for convenience and improved reproducibility.

Uses the nozzle as a probe and therefore has no x/y offsets and minimal z offset.

Accurate to 0.01mm or better and reproducible.

The aim was to devise a z-probe which was: Some are more accurate, convenient and useful than others. There are many z-probe technologies in use in 3D printing, ] however each has its advantages and disadvantages.