When I had my featherweight in for service, I mentioned how it had started running very slowly lately. My repairman suggested swapping out the motor. It's pricey, which is why I haven't done it yet. I didn't get more than a 1/2 hour or so on it yesterday and it was very sluggish, so I decided to put it aside and get my Viking Sapphire out.
Each machine has a 1/4 foot, but they do not sew the same size seam. The one for the featherweight actually sews more of a scant 1/4 and the one for the Viking is a tad over. I knew that when I changed machines, my seam allowance would change. Just on chance, I decided to take the foot off the FW and put it on the Viking. I had to take the ankle off and screw the foot directly to the Viking (the ankle allows snap on feet). The Viking does have a 1/4" setting, but I do much better with the metal guide than just lining up with the edge of the foot.
I don't know why I never thought to try that before...DUH! LOL