What causes banding from one print to another?

[buggyjr12]

What causes banding from one print to another? I print one batch of decals and everything looks great. Print a second copy of the exact same thing, five minutes later, and it has banding lines.

The only thing I did was an enviro-match between prints because I got a scan motor error at the end of the first print and had to shut the machine off. When I powered it back up it did a self-cleaning. Hard to believe an enviro-match and a cleaning cycle would make it print worse.

I'm printing on a Roland SP-540V in standard (painfully slow) mode. I've never had banding in standard mode before.

Ahhhh - one other thing I just remembered is that I changed rolls of vinyl. Same material (IJ35C), just a new roll.

 

[buggyjr12]

Update: I did another enviro-match and it's printing fine again. Who knows....

 

[Solventinkjet]

The print feed calibration can change throughout a roll due to the weight difference between a new roll land almost empty roll. The fact that you got a scan motor error could mean the encoder strip or sensor is dirty as well. Failing dampers would also cause intermittent banding. Sounds like it might have been a fluke in your case though.

 

[buggyjr12]

The print feed calibration can change throughout a roll due to the weight difference between a new roll land almost empty roll. The fact that you got a scan motor error could mean the encoder strip or sensor is dirty as well. Failing dampers would also cause intermittent banding. Sounds like it might have been a fluke in your case though.

I think it was a fluke. The dampers and encoder strip/sensor are all new. I got the scan motor error because I tried to get a 65" print out of 70" of material but the adhesive that holds the vinyl onto the cardboard tube stuck on the back of the machine and caused it to tug.

That's what I get for being in a hurry and thinking, "it should (probably, maybe, hopefully, please please please) be long enough to make it," instead of just unboxing a new roll and loading it on. I had to throw the print away and unbox the new vinyl anyway.

Also, I know I said "scan motor error," but it was probably a "feed motor error." It's been a whirlwind around here lately.