Strain Gage question

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Caito
13
Joined: Tue Jun 16, 2009 4:30 am
Location: Switzerland

Strain Gage question

Post by Caito » Mon Oct 23, 2017 9:40 am

Hi everyone!

I have a question regarding strain gages. For applications not requiring too much precision (10%), do you think it is a problem if you place a strain gage on top of the paint, instead of directly to the metal?

For example, in a coil spring which has been coated with some paint to protect it.


Thanks!!
Caito
Come back 747, we miss you!!

Greg Locock
165
Joined: Fri Jun 29, 2012 11:48 pm

Re: Strain Gage question

Post by Greg Locock » Mon Oct 23, 2017 10:54 am

I reckon the installed, calibrated, cost of a strain gauge is about $100. Is it really worth risking that for the sake of a couple of minutes with emery paper? On the other hand if the paint is properly bonded to the metal then its like glue. And you glue the strain gage.

CAEdevice
36
User avatar
Joined: Thu Jan 09, 2014 2:33 pm
Location: Erba, Italy

Re: Strain Gage question

Post by CAEdevice » Tue Oct 24, 2017 9:53 am

Caito wrote:
Mon Oct 23, 2017 9:40 am
Hi everyone!

I have a question regarding strain gages. For applications not requiring too much precision (10%), do you think it is a problem if you place a strain gage on top of the paint, instead of directly to the metal?

For example, in a coil spring which has been coated with some paint to protect it.


Thanks!!
Caito
You could use a very large (long) strain gage, it will filter the median strain but if you don't need precision it could work.

Tommy Cookers
511
Joined: Fri Feb 17, 2012 3:55 pm

Re: Strain Gage question

Post by Tommy Cookers » Tue Oct 24, 2017 6:50 pm

install it and follow the response through time to a step loading and step unloading of the spring

Caito
13
Joined: Tue Jun 16, 2009 4:30 am
Location: Switzerland

Re: Strain Gage question

Post by Caito » Thu Oct 26, 2017 12:02 pm

Thanks all for your answers!

I'll evaluate and let you know. This is not for a dynamic application, that's why precision is not of importance.

We'll see how it goes :D
Come back 747, we miss you!!