JE Adams Combo Vac silver button high failure rate

[OurTown]

I use E-Switch's red ring LED switches for Nayax external stop. Nayax outputs ~5vdc. I install a 330-350ohm resistor in series to prevent LED burnout.

I checked the illumination voltage output on a Cryptopay swiper and it was right at 2VDC. The red illuminated ring E-Switch buttons are rated at 1.8V so I'm going to let that go without a resistor. Someday I'll check the voltage of the JE Adams board output to see if it is too high for the Bulgin buttons.

 

[cantbreak80]

What would people suggest for soldering the Bulgin buttons? Spec sheet says they’re silver. In searching I can get silver braze rods but that would seem too much heat for the button to bare.

While I don't use it that much anymore, my bench features:
Weller Soldering Station
Kester Solder