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Topic: Reverse mounting tactile switches (Read 17640 times) previous topic - next topic

majenko

I suppose I could just scrap the whole reverse mounting idea for buttons if the buttons are tidy enough.  I have just found something which might do admirably.  It's surface mount, not through hole, but most of the contact is underneath the body with only a small tab to each side.  And they are available in red, green, grey and white:

The Omron B3AL1000P, about 6mm², the price is reasonable, and the reflow profile is within my abilities to conform to.  I could compromise for those buttons I guess.

graynomad

#16
Nov 18, 2013, 02:24 am Last Edit: Nov 18, 2013, 02:29 am by Graynomad Reason: 1
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(two are every large)

Quote
until you realise the tabs are only 0.5mm x 1.4mm

Yes it's all relative, it's a tiny switch :)

What about things like the NKK JL series (http://www.nikkaiswitches.com/default.asp), they are PTH with no visible legs. I can't find them on their useless web site but if you look around you may stumble across them (no bloody search facility, WTF?)

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

graynomad

Found them

http://www.nikkaiswitches.com/metricpdf/jl.pdf

Can't link to the product page because it's a stupid Flash or something site, but look in the "illuminated Tactile" section.

There's bound to be others as well.

_____
Rob
Rob Gray aka the GRAYnomad www.robgray.com

majenko

Nice, but actually a bit too big now ;)

The panel size I am looking at is (iirc) 48mm x 32mm (or something close to that), so it needs to be small, but not too small ;)

TomGeorge

#19
Nov 18, 2013, 12:46 pm Last Edit: Nov 18, 2013, 12:48 pm by TomGeorge Reason: 1
Hi, looking at the diag with reply #2.
I see that you need a tactile switch that will mount in the hole and solder up under the PCB.
Although you can get ones with tabs that allow this way of mounting them, the problem is the strength of the switch because it has no backing, most tactiles are designed to have back support.
So is there a problem with you backing  up the PCB with another blank PCB with some thin, ie 1mm,  cushioning material to make up for the irregularities in the back of the switch.
This way you have the switch mounted low in the front PCB with a rear PCB to provide the support the switch was designed for?

I have had to do this with some temperature controllers that had to be refurbished and the slim profile tactiles have not been available.

Tom.... :)
Everything runs on smoke, let the smoke out, it stops running....

majenko


Hi, looking at the diag with reply #2.
I see that you need a tactile switch that will mount in the hole and solder up under the PCB, the problem being strength of the switch because it has no backing, most tactiles are designed to have back support.
So is there a problem with you backing  up the PCB with another blank PCB with some thin, ie 1mm,  cushioning material to make up for the irregularities in the back of the switch.
This way you have the switch mounted low in the front PCB with a rear PCB to provide the support the switch was designed for?

I have had to do this with some temperature controllers that had to be refurbished and the slim profile tactiles have not been available.

Tom.... :)

I had thought about that, actually - making a small module for each switch, so it sits on its own small PCB, and then that PCB is mounted on the rear of the board providing a much larger solder area for strength.  It has a rather large impact on the overall cost of the build though, so I'd rather avoid it if I can.

It looks like I'm going to have to go with front mount, and look for the tidiest, most hidden solder joint, buttons I can find.

Riva

http://uk.mouser.com/ProductDetail/Marquardt-Switches/30030452/?qs=sGAEpiMZZMsgGjVA3toVBCBkrrIph%252bvFiOiFAE4O4UY%3d

http://uk.mouser.com/ProductDetail/CK-Components/D6F90-F1-LFS/?qs=sGAEpiMZZMsgGjVA3toVBBpDTNTTW0j3aWEvuHK92Mc%3d

http://uk.mouser.com/ProductDetail/CK-Components/KS12R22CQD/?qs=sGAEpiMZZMsgGjVA3toVBMGoe4EMCjcf8SHRlndBMc0%3d

http://uk.mouser.com/ProductDetail/E-Switch/32001E11BLK/?qs=sGAEpiMZZMsgGjVA3toVBE0x9sLV9vZBBbRW4B6dddU%3d
Don't PM me for help as I will ignore it.

NANDBlog

1. Buy a panel mount switch
2. Make a hole on the PCB big enough
3. Fix the switch like any other one
4. Solder the wires on the PCB
5. Profit

graynomad

Did you ever come up with a good solution for this Matt, I find myself in the same situation now and although I do have other options a small reverse-mounted switch is my preference.

_____
Rob
Rob Gray aka the GRAYnomad www.robgray.com

Shpaget

Dave from EEVblog came up with, what I consider, a neat solution.
http://www.youtube.com/watch?v=NCeSgpPWnsc

graynomad

Yeah that's the idea, but it needs two PCBs, I can only have one that has to do the lot, unless I can think of something to make that work.

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

majenko

Best I have come up with is a discrete thorough hole - nothing that is both reverse mount and rugged :(

graynomad

OK, I've given up on this for the time being. Luckily in my case the front panel PCB connects at right angles to the main PCB, so I can use RA switches on the main PCB that have the actuators poking through the front panel.

It's less flexible because the switches have to be in line with the main PCB, but it will work OK.

______
Rob
Rob Gray aka the GRAYnomad www.robgray.com

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