Clear Sight: How to Use a Pick Glass

Are you blessed with perfect eyesight? No? Me neither! I’m a proud member of the glasses-wearing club and embrace tools that can help me achieve good cloth without straining my eyeballs. If there is one thing I have learned as I continue my adventure in weaving with fine yarns, it’s that I need help to see how closely I’m beating the weft. And that is where the pick glass comes in handy.

What Is a Pick Glass?

A pick glass, or linen tester, is a small magnification tool that you can use to inspect your fabric surface. You can find them in different shapes and sizes, but typically a pick glass consists of a magnifying lens (often 8x or 10x) and a measuring scale. Some have an adjustable focus, or even an LED light, but the simplest ones I’ve found have a fixed focus lens, cover an area of one square inch, and fold up into a nice and neat little package.

Why do I need a Pick Glass?

When you get up close and personal with the surface of a fabric, you can see the individual threads and how they interlace with each other.

You can count the number of threads along the scale to determine the fabric’s thread count. (This is soooooo much easier to do when you aren’t straining to see the threads!)

A pick glass will work regardless of whether the fabric is on the loom or off the loom, whether you wove the fabric yourself or it is a commercial fabric. The fact is, if you have trouble seeing the individual threads at all, then a pick glass will help you check the fabric for things like:

if your warp and weft threads are evenly spaced and tensioned
if there are any gaps, skips, or floats in your fabric
if your pattern is accurate, and if there are any mistakes or variations in your fabric
if the yarn is spun or filament, single or plied, smooth or textured, S-twist or Z-twist
if the weave structure is plain, twill, satin, basket, etc., then how the warp and weft threads cross over and under each other

How to Use a Pick Glass

To use a pick glass, simply place it over the area of fabric that you want to examine. You can adjust the focus by moving the lens closer or farther from the fabric. My little 5x fixed focus lens pick glass is designed so that when you place the base on the fabric and look through the lens, the measuring scale and fabric surface are always in focus.

To use a pick glass:

Place the pick glass on the fabric and, if necessary, adjust the focus until you see a clear image of the threads.
Align the scale with the weft threads and count how many picks are in one inch or centimetre. This is the pick count of your fabric. Rotate the pick glass and repeat for the warp threads.
Compare the pick count with the desired or expected value for your fabric. If the pick count is too high or too low, you may need to adjust your loom tension or your beat. Or maybe even reconsider your sett!
Move the pick glass around different areas of your fabric to see if there are any variations in pick count, thread thickness, colour, or weave structure. These variations might indicate uneven tension, skipped threads, broken threads, or other weaving errors.

On my loom are upholstery samples with 16/2 Ne cotton set densely in both warp and weft. And that cotton is black. Talk about straining to see the individual threads! If you have a fabric on the loom that is dark or tightly packed, my suggestion is to shine a light on the back of the fabric. Backlit, you can see all the spaces between each thread.

Yep, I Carry a Pick Glass in My Purse

If you are a weaver who wants to take your craft to the next level, you should consider getting a pick glass and using it regularly. A pick glass is easy-to-use and affordable. It can fit in your pocket, that little bag of tools near your loom, or even your purse.

At my loom, it has been a lifesaver with this black warp. But I also take it with me while I’m out-and-about.

I’ve filled my phone with photos I’ve taken where I’ve shot through the lens of the pick glass. Upholstery fabrics in situ, whether on the train or in a café, are a wonderful source of inspiration!

And it has been helpful as I take a closer look at my collection of samples and swatches.

A train trip in Scotland was a wonderful source of inspiration both inside and outside the carriage! A quick photo with the pick glass and I have lots of information to look at later. The black and blue are hard to tell apart without the pick glass.

You can find simple or fancy pick glasses online, where they are just as likely to be marketed to the textile industry as they are to the printing and publishing industries. It’s fun to take a closer look at textiles… but it is even better to do it without strain!