Monroe, I don't think you will need an adapter. Featherweights are short shank machines and many other machines are too. Try the feet you have. Likely as not, they will fit and work just fine. Likewise, the feet and attachments for a featherweight will probably fit other machines. I use my buttonholer that came with my Featherweight on my Janome 6500 machine and it works beautifully (the built in buttonholer on my Janome won't handle large or thick buttons).