As much as it is possible to buy an adapter to use the piece that comes with the sanding disks on a dremel, do NOT use a dremel to sand polymer clay. Unless you have a supremely steady hand and perfect control, due to the high speed rotation, it will EAT UP your polymer clay. That is the reason the pedicure wand is needed.
To make this whole thing short:
You need a pedicure wand.
Why pedicure wand and not something else, like an electric nail file, or defoliator, etc? Simply because the electric nail files are usually quite flimsy and pretty much made out of plastic and cordless. The ones that aren't... well, are quite pricey.
I looked for one that would have 3 qualities: be made out of metal, be corded and be of a decent price. The fact that the pad is almost 2" also helps.
This is the one I chose:
I bought it from Amazon USA HERE
For people in Europe and other continents, I found it on Aliexpress HERE
I also found it on Amazon UK HERE
Also on Amazon Germany HERE
I also chose a set consisting of a drill pad with a full assortment of sanding discs, that are wet sandpaper.
Again, for people in Europe and other continents who can't buy from USA Amazon, I found these too on Aliexpress, only that the set that has the foam pad has less grits and can be found HERE but you can buy more discs of various grits HERE
For UK people I found it on Amazon UK HERE
Amazon Germany you can find the kit HERE
You can purchase them both from my Amazon Influencer store, in the "sanding" section of the store. Just click HERE.
This set comes with a sponge pad, with velcro on one side, that is supposed to be put on the drill pad.
For people who live in other countries with Amazon: I do not know how the items are called in your language so I couldn't search. Essentially the wand is called "electric callus remover" and the sanding discs kit is "2 inch sanding discs hook and loop with foam pad"
How to use:
Simply
glue that sponge pad on the pedicure wand's pad using Superglue,
Gorilla Glue or Loctite (I used Loctite) and let it harden properly for
24 hours.
And you're good to go.
I
suggest that you use a permanent marker to write the grit on the back
of the sanding discs, as they don't have that, and it will be easier for
you to figure out which is the one you want.
Of course, you can choose another brand, for each of the two things you need, but these are the ones I found the best deal for the price.
Cost of both is $40. Much cheaper, much better quality than Polyfast and also it's CORDED, no more batteries!
NOTE: this will not substantially shorten the time you spend sanding, as you still need to sand thoroughly, but it will definitely not be hard on your hands.