Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie
Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

Strain gauge/spring help

  • 13-01-2016 2:40pm
    #1
    Daniel S
    Registered Users, Registered Users 2 Posts: 3,533 ✭✭✭


    Hi,

    I'm trying to build a rig which measures deflection using cantilevers and strain gauges. The maximum force that can be applied by the end of the beam is 3N and I need 15mm of deflection.

    I can work out the maths, but what I'm asking for help with is the choice of material. I'm afraid making it too light will make it inaccurate.

    Would 0.1mmx5mm (cross section) strips of stainless steel be okay to use with a strain gauge?


Comments

  • #2
    CJhaughey
    Registered Users, Registered Users 2 Posts: 14,907 ✭✭✭✭CJhaughey


    Daniel S wrote: »
    Hi,

    I'm trying to build a rig which measures deflection using cantilevers and strain gauges. The maximum force that can be applied by the end of the beam is 3N and I need 15mm of deflection.

    I can work out the maths, but what I'm asking for help with is the choice of material. I'm afraid making it too light will make it inaccurate.

    Would 0.1mmx5mm (cross section) strips of stainless steel be okay to use with a strain gauge?
    0.1mm is very thin, thinner than paper.
    I would think you would need something like 5mm tube to get reasonable stiffness in a rig.
    Can you provide a sketch of what you want to make?


  • #3
    Daniel S
    Registered Users, Registered Users 2 Posts: 3,533 ✭✭✭Daniel S


    CJhaughey wrote: »
    0.1mm is very thin, thinner than paper.
    I would think you would need something like 5mm tube to get reasonable stiffness in a rig.
    Can you provide a sketch of what you want to make?

    5mm is far too thick. I'm thinking the thickness of the balance spring in a watch. I just don't know if I can use strain gauges on something that light.

    I looked up the thickness of an aluminium can and they seemed to be around 0.1mm. If you could imagine cutting a strip out of the centre of the can, that's what I'm looking for. Could a strain gauge be placed on a material as thin as that?


  • #4
    CJhaughey
    Registered Users, Registered Users 2 Posts: 14,907 ✭✭✭✭CJhaughey


    Daniel S wrote: »
    5mm is far too thick. I'm thinking the thickness of the balance spring in a watch. I just don't know if I can use strain gauges on something that light.

    I looked up the thickness of an aluminium can and they seemed to be around 0.1mm. If you could imagine cutting a strip out of the centre of the can, that's what I'm looking for. Could a strain gauge be placed on a material as thin as that?
    I am having difficulty visualising what you are trying to do.
    Can you draw a sketch in Paint and post it?


  • #5
    Daniel S
    Registered Users, Registered Users 2 Posts: 3,533 ✭✭✭Daniel S


    CJhaughey wrote: »
    I am having difficulty visualising what you are trying to do.
    Can you draw a sketch in Paint and post it?

    I think I have it sorted now. I went and bought a stainless steel feeler/thickness gauge and I now have a range of thicknesses to test, which I feel are worth testing. :) 0.1-0.4mm :D

    Thanks CJ for helping! :)


Advertisement