View Full Version : [Question(s)] Force Sensing Resistors

06-30-2008, 01:52 PM
I would like to cut the FSR .5 inches and .2 inches. Is this possible? If so I would like to take the pins that are coming out of the base of the sensor and place them right by sensor itself. Could you please tell me what the name of the pins are and the size as well to? I would also like to know what tool to use to unclamp the pins. Thanks

06-30-2008, 01:59 PM
In theory you could cut some length off the leads but NOT off the pad. It will change the resistance slightly.

Mine are 0.10" on center pins. You could solder any pin on there you like. Leave enough space to GENTLY scrape the plastic away from the trace and solder with as low a heat as you can possibly get away with, and make it quick!

06-30-2008, 02:01 PM
Unless you either have a budget high enough that you don't mind quite a few failed attempts or have done this before, you don't want to mess around with moving and re-clamping the pins. We've had more customers than you can imagine try to re-clamp those pins and they were all failed attempts.

It's not a matter of trimming the tails down. That part is easy. It's trying to get those dang pins to attach (and work) correctly after re-clamping them.

06-30-2008, 02:03 PM
Soldering tabs on there should work with no problem though:) It won't look as clean looking as the clamps (except if you're Master Guru Adrenalynn soldering kind of good, haha), but it won't be near as difficult either.

06-30-2008, 02:19 PM
I don't know if I'm "all that" but you are proper to note that it's not for the faint of heart. Clean them to within an inch of their lives (probably denatured alcohol wipes or gold wipes in this case), and tin the heck out of them. I would use multi-core solder, but then I always recommend multicore solder... I might also be tempted for someone not all that comfortable with a soldering iron to recommend "conductive tape" or "conductive adhesive" and then roughing-up the back side and JB-Welding all the way around it or something similar to stress-relieve it...

There are instructions out there for creating your own conductive adhesive, although I haven't tried 'em - I pride myself on being able to solder anything. . . ;) No - seriously though, I've used it for attaching grounding pads for RF. Just be aware that conductive adhesives will change your resistance, sometimes radically.

This does seem like a good time and place for it though.

Edit to note: If you're going to use them in a socket or in a breadboard (why else keep the pins? ;)), make certain you measure carefully to a standard spacing, like 0.10". I usually use a micrometer and draw lines on a piece of paper, then use that underneath as a template. Keeps 'em straight and aligned.