Stan made some comments about the paper and which way it faces affecting Curl.... These are pretty right on... Since we produced software the formats stuff for LJ, we have quite a variety of experience..... PROPER paper composition (chemicals, etc) do make a difference. And so does the side sometimes. The LJ IIIsi, can be more sensitive than say the LJ 4. LJ 4 usually can handle paper put thru a second time. The LJ IIISi is more sensitive. Also, if you are compressed and duplex, then you aggrivate the situation.... That is all I know..... Marty Indreboe