HI Nada, thank you for the links to the other templates! I had seen on your site the ones with more open heels and wondered if they were a variety of your own design. It seems like the fit/length wouldn't be as important if the heel is more open or even flat.
I received the rubberized microfiber fabric in the mail. Pics of it are on my Flickr page: www.flickr.com/photos/23720908@N02/ I'm not sure I like it, but am withholding judgement for now. It looks like a microfiber piece of fabric that has been fused on one side with thin textured rubber. Also the color doesn't really go well with the blue yarn of the slippers. The leather soles haven't arrived yet. I guess I'll have to decide 1-how slippery the leather feels and how it might wear, and 2- whether being kind of ugly and non-slip for at least the short term (before potentially turning soft and gluey) would be better than my mom sliding and falling on the floor. I suspect the latter will win out.
I do want to try to felt ones from a template, though, and maybe they will turn out better. Also will be adding some decoration, probably stitched on in a light colored yarn, to the blue ones I already made. They look too plain and a little sad.
I shouldn't be so critical of the rubberized fiber. It might be just what you're looking for, Carole, and might be what I will use, too! Here's the link to where I bought it on Etsy. www.etsy.com/transaction/1364702439
Everything with the seller was fine, professional, and with fast delivery; and the product is almost exactly as described (the color of brown is not quite as warm-toned as in the pic--I probably should've gotten the beige/cream or the black one). The size of the sheet is big enough to make at least three sets of soles.
I've not added grip to slippers, but I have to felt mats/trivets. I've used silicone and rubber shelf/draw/mat underlay stuff. The rubber mat was great, but I used it on a felt mat I made my brew on, so after a few washes, that shrank-and the rubber mat didn't. Probably less of a problem for slippers?
The silicone is great, I use Wilko's bathroom/Kitchen clear silicone, and spread it with my finger.
I wonder if, in general, it might be better to spray/spread etc the grippy stuff to some other (less fibrey) fabric and then attach to the slipper the way other attachable soles are?