Interpretting Micron Tests Pt. 1

This past month while we were skirting and skirting and skirting we collected samples from all of our finewool fleeces and sent them off to Texas AgriLife Wool and Mohair Research Lab for micron testing. We sell fleeces to handspinners as well as sending them to small mills so we really wanted as much information as possible about the product we are growing.

The testing was super fast and they sent us so much information! Here's the first page of what we received.

As you can see it lists all of the animals we sent samples of and a whole bunch of letters and numbers that don't make a lot of sense at first. I'm going to dig deep into my college stats class memories to break it down and see what it tells us.

The first column is the average micron count, or the average diameter of the individual fibers in each sample. Just for reference a human hair averages 40-80 microns wide. For Benny, one of our natural colored cormo crosses, his fiber has an average micron count of 21.2 putting it at the high end of the fine wool range.

  

The next column is the standard deviation between micron sizes of the many fibers in each sample. This is a measure of how different the micron count of individual fibers are from the average micron count. The smaller the standard deviation, the more uniform the fiber is and the easier it will be to spin. Mr. Ben's SD is 3.9, a small number indicating a fairly uniform micron count throughout his fleece.

Up next is the "CV mic" column which stands for coefficient of variation in microns. This is another measure of variability within the fleece sample but instead of measuring the variation in microns it gives a percentage of deviation between fibers. Benny's CV is 18.5 (that's a percentage remember) and anything under 21% is considered "excellent" standard of uniformity so once again Ben has done a good job.

The next two columns break down just how fine the fibers are a little more with a few percentage. "<15 %" is the percentage of fibers in the fleece under 15 microns while "CF %" is the weirdly named comfort factor percentage or the percentage of fibers under 30 microns. As you can see only 2.2% of the fibers in Benny's fleece sample were under 15 microns, but they are almost all under 30 microns making it a nice, next to skin soft fleece with very very few prickly hairs.

In the very last column is a measure of how the wool will be in a spinning situation in a sort of confusing category called Spinning Fineness. Its calculated using the average micron count and the CV.  It gives an estimation of the quality of the fiber for spinning where the smaller the number the better.

This whole section of the report can also be summed up with a histogram, a sort of graph. A very fine, consistent fleece will have a skinny little curve towards the left of the table. A less consistent fleece may have a big wide hump spanning many microns. Here's Benny's histogram, tall and skinny and nearly completely under 30 microns. Way to go Ben!

There's a whole other section dealing with staple lengths but I think this post is getting long and confusing enough so I'll save that for another day. I hope you all found this as interesting as we did and he's a picture of the famous Benny (actually named Beignet) for your time.