rotarius
@sbank, you don’t need a cart to be rectangular or have parallel sides, all you need is symmetrical sides and a measuring tool like calipers. I do agree, the cantilever needs to be in line with the cart axis. Eyeballing with lines on a mirror is less precise, at least with eyesCalipers? I don’t think that’s a good tool for phono cartridge alignment. @sbank I agree with you - nothing is better than a good mirrored alignment gauge. I like the WallyTractor, but there are others as well. A WallyTractor aligns the cantilever - not the phono cartridge body. So if the cantilever itself is a bit out of alignment - and many are - you’ll still get good results. Using the reflection in the mirror also has the benefit of magnifying the amount of alignment error, simplifying the process. A magnifying loupe can also be used.