Dennis some suggestions you can take or leave.
You should look for specifications on your electronic gauges, they will often have a spec on change with temperature, there can be a big difference with different designs and manufactures. Some of the newer electronic stuff is surprisingly stable. I think your idea of using a gauge block to verify is good. You can check if leaving the electronics turned on or turning off each time is better.
As far as measuring creep over time I would suggesting adding more data points, record the deflection at various points in time like in sort of an exponential time scale, like 5 sec, 20 sec, 1 min, 5 min, 20 min, 2 hrs, 10 hrs, 1 day, 5 days, 2 weeks, you get the idea.
Another thing to consider is to record the deflection as the force is increased in several steps then decreased in several steps. Repeat the cycle a couple of times. If the deflection is not linear with force, or different between increasing and decreasing or changes test to test it suggests some measurement or setup errors that will be interesting to get to the bottom of. Sometimes there will be a relatively large deflection at a small force then become more linear. In any case having an idea at what force it starts to deform plastically relative to the creep load you are applying.
If you really want to make a science project it would be interesting to flip the bar over and see how the creep or elastic deflection changes as a result of previous loads in the opposite direction. At least food for thought as you design the setup. It has always seemed to be that plastically loading it in one direction results in a different effect when subsequently loading it in the opposite direction.
A long pointed rod, loosely guided to be vertical above the center might be a straightforward way to add dead weights, of coarse what you really want is is a load cell with all force, deflection and temperature data read into a data acquisition system LOL. I expect much of this is way beyond the scope of what you want to do but you did ask for comments...
You should look for specifications on your electronic gauges, they will often have a spec on change with temperature, there can be a big difference with different designs and manufactures. Some of the newer electronic stuff is surprisingly stable. I think your idea of using a gauge block to verify is good. You can check if leaving the electronics turned on or turning off each time is better.
As far as measuring creep over time I would suggesting adding more data points, record the deflection at various points in time like in sort of an exponential time scale, like 5 sec, 20 sec, 1 min, 5 min, 20 min, 2 hrs, 10 hrs, 1 day, 5 days, 2 weeks, you get the idea.
Another thing to consider is to record the deflection as the force is increased in several steps then decreased in several steps. Repeat the cycle a couple of times. If the deflection is not linear with force, or different between increasing and decreasing or changes test to test it suggests some measurement or setup errors that will be interesting to get to the bottom of. Sometimes there will be a relatively large deflection at a small force then become more linear. In any case having an idea at what force it starts to deform plastically relative to the creep load you are applying.
If you really want to make a science project it would be interesting to flip the bar over and see how the creep or elastic deflection changes as a result of previous loads in the opposite direction. At least food for thought as you design the setup. It has always seemed to be that plastically loading it in one direction results in a different effect when subsequently loading it in the opposite direction.
A long pointed rod, loosely guided to be vertical above the center might be a straightforward way to add dead weights, of coarse what you really want is is a load cell with all force, deflection and temperature data read into a data acquisition system LOL. I expect much of this is way beyond the scope of what you want to do but you did ask for comments...