Looking for Piezo switch

[Packhorse]

I am looking for a Piezo switch to use for various projects. I have not used one before so dont know a lot about them

Who is using what? What are the pros and cons of each?

Obviously needs to be waterproof. Smaller than 25mm. Well priced. Compatible with micro processors.

 

[Codiak]

Pack, you have a lot of choices interns of manufactures. The real question is what features you want.
Solid? Self lit?

The main issue is they are mostly momentary. Two manufactures have prolongated versions that allow for presses but they are expensive and require bulk orders.

Allied electronics has a good selection

 

[Klem]

I've used two types...both M16 (16mm diameter), the smallest diameter the regular manufacturers make.

1. Schurter M16, aluminium body, from either RS Components or Element14 (formerly Farnells). $35-$45AUD each. For momentary action.
http://australia.rs-online.com/web/p/push-button-switches/4561852/

2. Baran, aluminium body, from Everswitch in Oz, $45AUD each.
http://www.barantec.com/products/piezo-switches
I use the SMF16 prolonged momentary action for Taskled's drivers.
http://www.barantec.com/switches-smf

• Everswitch will sell the prolonged's individually but I purchase 3 at a time, to make the postage worth it.
• An M16 fits a Maglite switch hole (17.2mm) perfectly.
• You can get toggle versions but switching current is max 0.5A
• All waterproof.

 

[Packhorse]

I dont need pro longed. Momentary is fine.
Not sure what you mean by solid and self lit.

I had looked at the Schurter M16. Only rated at ip67??

 

[Klem]

Then the standard Schurter in '1' above is what you are looking for.

I think Codiak is referring to the fancy piezo's with inbuilt LEDs to light the switch. Something like this;
http://australia.rs-online.com/web/p/push-button-switches/4178646/

I've always thought that would be a nice touch having the switch glowing underwater, but I worry about the higher cost and waterproofing.

As for IP67, this refers to the back of the switch where the wires/contacts enter. Once sealed in your torch only the front will be exposed to sea water/pressure and this is as waterproof as solid metal can get, down to the depth you will plan to take it.

 

[girdles]

RS Components stock No 708-2927

 

[Klem]

RS Components stock No 708-2927

Definitely the right type of piezo but the price is way out ($72.50)

Type 'piezo switch' into the search engine of RS Components and then sort by price. Anything under $40 is a bargain.

 

[Packhorse]

Thanks. Looks like I have a growing shopping list with RS

 

[josb]

Hello Packhorse,

I don't know if you can find a supplier who sells APEM switches in New Zealand but they also have the piezo switches in their program, see this pdf file: http://www.produktinfo.conrad.com/d...-01-de-PIEZOTASTER_16MM_NATUR_PBAR1AF0000.pdf
a web company where I can buy from here in the Netherlands sells the standard version for € 29,61 (http://www2.conrad.nl/goto.php?artikel=707024), this company is based in Germany and they send worldwide (www.conrad.de).

 

[girdles]

Definitely the right type of piezo but the price is way out ($72.50)

Type 'piezo switch' into the search engine of RS Components and then sort by price. Anything under $40 is a bargain.

£23 uk

 

[Codiak]

Then the standard Schurter in '1' above is what you are looking for.

I think Codiak is referring to the fancy piezo's with inbuilt LEDs to light the switch. Something like this;
http://australia.rs-online.com/web/p/push-button-switches/4178646/

I've always thought that would be a nice touch having the switch glowing underwater, but I worry about the higher cost and waterproofing.

As for IP67, this refers to the back of the switch where the wires/contacts enter. Once sealed in your torch only the front will be exposed to sea water/pressure and this is as waterproof as solid metal can get, down to the depth you will plan to take it.

Thanks Kelm,
That's exactly what I was referring too.
While I've yet to dive with one you can also get the switches with tactile feedback.

I was unaware that everswitch was selling single units, time to find a prolongated with integrated led.

 

[Packhorse]

RS delivered in under 24 hours. Nice little unit as so far so good. I also had the choice of any colour...as long as it was black.

 

[b-bassett]

I also had the choice of any colour...as long as it was black.

odd, i can get the full range of colours from RS uk, though i usually only use black anyway, matches a mag nicely.

not sure if you went for the momentary version, but they do make a latching one aswell (needs a fet for higher current though)

 

[Packhorse]

I went with the momentary.

Anyone just rely on the nut and O ring to seal or does everyone glue them in place?

 

[Codiak]

I went with the momentary.

Anyone just rely on the nut and O ring to seal or does everyone glue them in place?

I JB Weld them into place

 

[b-bassett]

jbweld here aswell,

id have thought the o-ring would be ok, but i prefer overkill.

 

[Klem]

I went with the momentary.

Anyone just rely on the nut and O ring to seal or does everyone glue them in place?

In earlier torches I've used metal 2-part epoxy. The ultra-thin factory O ring and thin switch lip screams-out for something more secure, especially if the spot where it is going is not completely flat. In Maglights I don't use the O ring or even the locking nut simply because I can't get in there to screw it up...just JB Weld and hold it in place while it cures. I use masking tape on the switch surface to keep the JB weld from making it look untidy. They have never leaked.

For these torches below I swapped out the piezo's factory O ring for a thicker one, screwed it in, but then on the inside used polyeurathane just in case. It probably would have been wateproof without the sealant. I made the mistake of machining the first waterproofing area too narrow and then realised I couldn't get a socket in there to screw it up ...back to the lathe for these more recent efforts.

Because the piezo leads get in the way of a socket handle I used pliers on the outside of the socket to cinch it up. Looks a lot more tidy than epoxy around the outside and the well on the inside does not take any more length than the piezo requires anyway.

This one in Delrin uses the same idea of a waterproofing area on the inside. Like I said, with a thicker O ring and the piezo cinched firmly it would probably be enough, but sure is peace-of-mind if you don't plan to re-use the switch...

 

[lucca brassi]

In earlier torches I've used metal 2-part epoxy. The ultra-thin factory O ring and thin switch lip screams-out for something more secure

IMO: epoxy or anything with mixed-in solvent , I think It's not get together very well because it eats out rubber , or rubber become just fragile.