If the print is stretchy, lots of time you'll see the line where the transfer tape was if you put a strip on to start the application. It works, but if the print is giving you stretch problems already, then you'll have 6" unstretched vinyl and then the same current problems on the rest of the
sign.
We rarely (I'm trying to think of when we have) laminate corrugated
signs and most of our prints are full coverage. What Orajet material are you using? I'd highly recommend switching over to 3165RA first of all for coro. The air release can become your best friend.
How long are you letting the prints set before you try to apply them? You really need to let them sit at least a few hours - if not overnight - before you try to apply. The vinyl will be much less pliable.
How are you hinging the print to apply? From a side? The top? Center hinge? If you are applying from a side, are you slowly rolling back the backing
paper as you apply - keeping it as low as possible to the coro? It helps to keep as little room as possible between the substrate and the print.
How are you on the laminator? Is it feasible for you to run them through there? (Although you will still get some of the stretch problem if you try to do it too soon after printing).
just some thoughts...