I've repaired those series Vikings and they're not the machine for you. They tend to need at least $150-$200 worth of parts and labor as they have issues that need addressing. The "self-lubrication" of these machines has turned to wax, typically making some of the knobs and buttons stuck. Forcing them means broken gears that are no longer available. If the cam doesn't work, that means it's cracked(they all crack due to age) and the part alone is $50. I have a couple vintage Vikings that I use rarely...they're just not great piecing machines. Get the Brother 1500 instead. You'd be much happier.