Extruder Tolerance - Preventing Blocking the Extruder - Working withCheaper materials

I have been experimenting with the tolerance of the input filament diameter. Which becomes and issue when working with filaments which have variable diameters along their length, usually cheaper materials. My  printer uses a input filament diameter of 1.75 mm and I have found that above a tolerance of 0.01 mm causes the printer head to block up, due to too much material being forced through the printer nozzle (A printer head block up is a slow and laborious task to clean out, and if it occurs during print the model is ruined). 

I have found that cheaper materials, bought online, usually have sufficiently good material properties, but have a less accurate diameter, which often varies through the material.

To overcome this issue, I recommend taking a series of precise measurements using a micrometer along the length of filament you expect to use in a particular print. Find the average diameter and then input this value into the G code generating software so that the rate of material input can by modified. 

In Cura software change this value:
(In the basic settings)

In Sli3r software you have to go into the filament settings and change it:

This is an additional process which is required only with lower quality filaments, but means a lot of money can be saved especially when printing large volumes. Lower cost filaments bought directly from China can be up to five times cheaper then branded materials from large companies such as Makerbot and Cubify.