I second strain gauges. There are many grades of cyanoacrylate that could cope with those conditions - although the humidity might prevent the glue from lasting forever. I've seen strain gauges used frequently for strain measurement on steam turbine housings, where ambient temperature can be in the 600-700 celcius range. On 10/11/06, Denny Esterline wrote: > > I'm working on a project where I will need to measure the weight of wooden > > blocks up to 4 kg's max. The hard part is they will be in a drying kiln so > > the conditions will be up to 100C and 100% relative humidity, or steam. I > > have looked into some load cells but they can be somewhat expensive. Before > > spending the cash to get one I wanted to see if anyone had any suggestions. > > > > Regards, > > Andy > > What level of precision will you need? > > 100 C and 100% humidity isn't realy that bad, you just have to think lateraly. > > My first instinct would be some sort of linkage to a more traditional scale outside the hostile enviroment, that might even include some type of hydraulic system (common automotive coolant, properly mixed, is good well beyond 100C) > > A mechanical spring ballance should be fine too, though it might need recalibrated at that temperature depending on your needed level of precision and the material used for the spring. > > Strain gauges are little more than a metal foil resistor, there's no reason why they couldn't be used in such an enviroment. You'll likely run into issues with bonding them, but that's solveable. And thermal compensation becomes much more important, but there are ways of dealing with that too. > > -Denny > > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist