Tactile switch NC ?

[exxos]

Been looking everywhere for a "all metal" switch like this, but normally closed.. such thing doesn't seem to exist ?!

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[DoG]

SMD?

[exxos]

SMD?

At this point I don't really care its like half sites don't put which they even are.

[DoG]

Is it the small height you are after? May I ask why you need it all in metal? I can find some tactile switches that is NO.

[exxos]

Is it the small height you are after? May I ask why you need it all in metal? I can find some tactile switches that is NO.

The size of the switch doesn't matter too much.. I want to use it as a Z-probe sensor.. But with a NO type, the nozzle will have to hit the switch and press it enough to contact.. which, if the contacts are iffy, it will just destroy the nozzle. But if it's a NC type, then iffy contacts are not so bad, I can detect that in software and warn etc, then as soon as the nozzle hits it, it will "break" the contact. Which is more reliable method IMO.

[dalek]

Could you go with the NO SMD microswitch for your Z-Stop controlled by software, but add in a hardware NC microswitch that cuts your z -axis power as a failsafe?

[exxos]

Could you go with the NO SMD microswitch for your Z-Stop controlled by software, but add in a hardware NC microswitch that cuts your z -axis power as a failsafe?

I am not sure that will be so easy, as the nozzle heights can vary a fair bit, so there would be nowhere to really put such a switch as it would always trigger or not trigger, in the wrong place.

The idea of the switch is to let the software know what the nozzle height actually is..

CNC machines (and voltera in fact) just use a contact pad.. which is pretty bad I think, as if it doesn't make contact (dust or whatever) the head will keep moving down until it's told not to.. in this instance, crushed nozzle again... Its basically a "open contact switch". I just don't want to risk that, I would rather have something enclosed.

[dalek]

...I am not sure that will be so easy, as the nozzle heights can vary a fair bit, so there would be nowhere to really put such a switch as it would always trigger or not trigger, in the wrong place.

The idea of the switch is to let the software know what the nozzle height actually is..
...

In that case I've been looking at this for my 3D printer: https://www.antclabs.com/bltouch I have one on order but it's been out of stock for a while

[exxos]

In that case I've been looking at this for my 3D printer: https://www.antclabs.com/bltouch I have one on order but it's been out of stock for a while

I saw that yesterday .. Plus loads of other odd things.. There's inductive ones and all sorts..

Have been wondering about an opto switch.. Problem mostly is keeping it clean.. I could move the nozzle back and forth and just keep lowering it until it breaks the beam . it would be good as its contactless , bit of a faff to go though all the steps but I guess it wouldn't take all that long and only has to be done once..

I guess software can "dust check" as the opto would be off when it's not supposed to be..

I think considering the nozzles are so fragile, bashing them on any switch isn't a great idea.. I think the voltera has a metal pad on a spring , as when the nozzle hits it, it goes downwards ...but I think over time it could may well damage the nozzle.. So I'll see what opto solutions there are I think...

[exxos]

Have been looking at sensors of all kinds... I have found these dust sensors which look interesting..

https://uk.rs-online.com/web/p/fibre-op ... s/6989110/

While these would be rather a overkill, I cannot really find anything else which is similar.. There are various optocouplers, but it is difficult to tell if something which is potentially 0.1mm in dia would actually break the beam or reduce the voltage enough to monitor the nozzle..

So I will see what optocoupler boards there are to play around with, but the dust sensor might be the way to go, as the nozzle can pretend to be a very large piece of dust!