I was taught that to set up your press to output consistently you need 3 parallel planes.
1 carriage rail/floodbar&squeegee travel path
2 screen (screen hangers)
3 platen (substrate)
Action wrote a post that went over this pretty clearly:
http://www.theshirtboard.com/index.php?topic=16560.0; I knew how to get a real nice parallel for all my screen hangers and platens, but the third plane, the carriage rail (the HEAD) wasn't really adjustable in the same way. And this bugged me for the longest time – if your heads were out of true from each other, you wouldn't HAVE three parallel planes.
The thing I was missing was – that the real 3rd plane was the squeegee travel path, NOT the carriage rail(/floodbar). If your carriage rails are anywhere near to close to each other, you're FINE,* because the
squeegee rides on air and has no problems correcting for minor inconsistencies/deficiencies. duh.
It was an ah ha, now I feel dumb moment when I figured it out. Just posting this in case anyone is chasing the same chickens in their head.
*if you want to be pedantic, and, I do – if your carriage rails aren't perfect (and they probably aren't) it WILL effect your floodbar, which will skate a bit front to back on a head that isn't perfectly level (if you set your platens and hangers to level).
If you REALLY want to scratch that itch without adjusting the heads, don't set your platens and hangers to level (F to B) but to parallel the head you print UB white with (if you want/need a floodbar there with ZERO skate to it). That's probably taking the thing too far, but that's what we do.