How to Tell if a Fiber is Superwash or Not...

or when in doubt get out the power tools!

I have a bit of a story to tell you today with lots of pictures! So a month or so ago I received a big order from a customer for Merino/Tencel Roving in a variety of colors. She makes felted art scarves, so it was very important it was Merino and not Superwash Merino. Well her order cleared out all the undyed fiber I had on hand and I had to order more. Roughly 8oz more for her order, plus more to replenish my stock on hand. 

Well, I got more of what I thought (and my supplier thought) was Merino/Tencel, only it wasn't. I received an email from my customer saying that 8oz was actually superwash and wouldn't work. So I contacted my wonderful supplier and they sent me more, saying they were sure it was Merino/Tencel. This time, to make sure I got out the power tools! Here is a sure fire way to tell if your fiber is superwash or not!

First take a small piece of fiber and dip it into some warm soapy water. Then squeeze it so it isn't too wet.

  

Then get out your electric sander. Make sure it is the vibrating kind, not the belt kind. Also make sure you plug it into a GFCI outlet, just in case. I plugged it into one in my kitchen. There isn't much water involved, but it's better to be safe than sorry! 

Put your bit of fiber onto a cookie sheet. Then turn the sander on and apply it to the sample. For these I moved it back and forth across the fiber for 1 minute on each side. Here are the results:

Merino Wool. I started with this one since I learned this technique in college and I wanted to make sure I was doing it right. Merino felts very easily, so this was a great sample to start with. This is Citrus, which I will dye upon request.

  

Merino / Tencel. From some fiber I had on hand from before. I knew this was Merino/Tencel and sure enough it felted up really nicely, even nicer than the straight merino. This is Owen, which I plan on dyeing more of very soon. Isn't it a gorgeous colorway?!

Superwash Merino / Tencel. Ever wonder what superwash really does when you try to felt it? Well wonder no longer. As you can see the fibers don't stick together and it's one matted lump. I could pull this back apart and spin it if I wanted to. It didn't change one bit from its previous form. This is Berry Pie. 

So, here is my mystery fiber I got from my supplier. I actually did this 2 minutes on each side, just to be extra cautious and give it every chance it could have. Now looking at the samples above to compare it, which one does it look like to you? It looks very much like the Superwash Merino / Tencel to me. So I emailed my supplier and they were hugely apologetic. They got immediately on the phone to the mill and ordered up a brand new batch of Merino/Tencel. 

 

So, when the new shipment arrived this week they sent me a little felted ball, which they tested in house. However, I couldn't resist getting out my sander again for a little test. This was one minute on each side and ta-da it looks just like how it should look. So if you have ever wondered whether the Merino/Tencel Roving I carry is really plain Merino, it most certainly is! Also if you have mystery fiber in your stash which you can't remember whether it is superwash or not, just get out the power tools and test it out!