Wednesday, July 07, 2010

Superwash vs Non-Superwash top

................... Two views of an experiment in correcting a labelling error.

The blue mini-skeins were each spun from what was labelled either Superwash or
Non-Superwash in the BFL Top. The results show clearly that we labelled the bins wrong!

Cannot tell you how I felt to receive two letters over the weekend from customers who swore that they did not get the spinning fiber they ordered. One expected superwash BFL; the other ordered non-superwash BFL. Both told stories with the same bottom line: it either felted, or didn't. And, we all know that superwash is not supposed to felt unless submitted to extreme condition.

That's what I tried to do with the experiment in dyeing first a 2-ply yarn and then a hank of roving. The yarn was dunked into almost boiling water for an initial soak, and lifted out by the choke ties and unceremoniously dipped several times more in the soaking bath. Then, they were tossed into a dyepot which was a little too hot and again subjected to the dipping technique, with a few swats of a long handled plastic spoon added for effect. The skein on the left held up from the first bit of abuse; the plies maintained their identification, and there was no spreading out of fiber as in the right hand side hank. The hank on the left side absorbed more color than the one on the right. Conclusion: Left side is Superwash, though not labelled as such, and right side is non-superwash, though, again, not labelled as such. Shame, shame.

The top reacted in the same way, but fpr one noticeable difference which was in the color of the top when it first hit the soaking bath before being dyed. The one of the left kept the white-white color, and the one of the right immediately darkened. The yellowish cast. which was more prominent on the right hand side raw fiber, is a clue that BFL might be superwash.

After much worse abuse applied to the top including stirring about in the hot dye bath, a series of swift thwacks to the bulk, and general agitation -- which we all know is one of the two necessary environmental requirements to make felt, the other being heat -- the theory formed from the skein experiment was supported by evidence of thick felting in one skein. Again, this fiber had been originally labelled as superwash, but it obviously was not superwash.

So, there we have evidence of the results of passing out one fiber to unsuspecting customers who just want to dye up some nice BFL top and are, instead, subjected to a rude experience.

I'm sorry.

Actually, we did a quick experiment in the shop and immediately saw the true non-superwash begin to cling together when first wet, and the color to deepen to the yellowish tone. This is true of superwash yarns and fibers. The chemical process does darken the fiber itself. The other immediate clue was the superwash fiber absorbed more color. It is darker than the non-superwash, regular fiber, and this is always true of superwash. The superwash process strips away the tiny scales which line each shaft of fiber, exposing the core to the dye. Instead of the dead scales disapating the color, the core of superwash fiber is exposed to the dyes without any shielding from the scales.

OK, all's fixed now. The bins are labelled correctly, and we are making it right with the few customers who purchased this confused lot in the past seven weeks. Again, my apologies for the mix-up!

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