We have been direct printing to ACM for 12 years so we have actually been able to see the longevity of many different ways. Which ACM can make a difference too. I didn't read anyone mention
sign direction and sometimes it's not always possible to know but I ask whether or not the
sign is south/west or north/east facing. That can make a huge difference in longevity. With our our first printer, the Gandiinnovations Jeti 3150, anywhere from 4-6 years was average lifespan before it started looking worn out. That being said, if it's under some sort of awning or north/east facing, 2-3 years longer. We then moved to an AGFA Jeti 1224 HDC, and it seems about the same longevity if not slightly less long term durability. My personal opinion was the change from a 50 picoliter dot to a 7 picoliter dot. Much thinner ink usage so not as durable. We've only hard our Titan HS for about 2 years so I'm not sure on real life longevity yet. I do know have a west facing
sign, printed on 10mil coro with primer that still looks perfect after 2 years so I'm hopeful that ink will last well on ACM. We UV liquid coat all of our outdoor prints so that helps add 1-2 years on top of the manufacturer estimated outdoor usage. Now we just feel out our customer. If its a permanent
sign on a building, we print direct and overlam with either 3m 8508 or 8518, depending on which way the
sign will be facing. Especially larger
signs, we tend to error on the side of overlam since I don't want a customer paying for a
sign and having it fail, and 1 either feeling like i should replace it at my cost or 2 make them pay for it. I haven't had a large overlammed
sign come back yet within that "it should have lasted longer than that feeling." I have seen a few at the 9-10 year mark that do look a little worn out but at that point, they need a new one.
So we print direct and liquid laminate for most of our
signs.
Signs we feel need the extra long term durability, we overlam. We don't print with solvent unless it needs to be reflective.