How to strech custom shapes without distortion?

I need to create a Template with different stencils with shapes that have a some specific features.

I am good with the templates, the stencils and basic shapes.

My issue is how to resize shapes. I need to be able to stretch the size on only a certain part of the shape while keeping the rest of the shape in it's original shape.

I thermometer would be a good example of what I am trying to achieve. I want to be able to make it look longer without being wider. I also do not want the bottom and head of the thermometer getting stretch and getting a odd shape.

I am using Visio 2010 premium.

I have read that custom line pattern could help, but I can't find enough details to figure out how to do it. 

Thank you Kindly.