Dealing with PVC vandalism

[joe]

The city called us, this week, with a complaint of vandalism on one of our park signs. They indicated it would most likely need to be replaced, and they were open to that.

Arriving on the scene it was evident there was a baseball sized hole in the background. I was fortunate to find the remaining piece that fell inside the interior cavity. What good luck.

No secret from here except we use PVC Gorilla glue to put it back together. Difficult to tell there was anything amiss. I did place a large PVC backer plate just in case.

http://www.talkshopbot.com/forum/attachment.php?attachmentid=31580&stc=1

http://www.talkshopbot.com/forum/attachment.php?attachmentid=31581&stc=1

http://www.talkshopbot.com/forum/attachment.php?attachmentid=31582&stc=1

[Tom Bachman]

Nice save!

[pro70z28]

Nice save. Hate it when stuff like that happens. Had a lighted sign for one of the schools here vandalize awhile back. It was a monument sign (2 sided). They ran a post through 1 side and cracked the other. They were 3/16" polycarbonate faces, so that had to take some doing.

[coryatjohn]

People can be so unthinking. I remember riding around in the back of a pickup at 14 blasting signs with a shotgun. Crazy.

[joe]

If this sign been made from Redwood or Cedar it wouldn't have broken but still trying to repair and repaint would have taken longer.
I'm wondering if the PVC will become more brittle with time. If it does there would be cracks or even breaks. All the materials I've other than wood, except PVC. has failed. The biggest failure was Medex followed by Extira. I feel kind of guilty since I posted lots of signs on, this forum, using them. The most expensive failures have been with HDU. I still use it some, when doing 3D carving, but only with 18lb. Then there's the grit. I guess I'll always be a wood fellow.

[pro70z28]

I've used Sentra, expanded PVC, outside in direct sunlight on a brick wall. After a few years it curled and got very brittle and chalky, although it did take a few years. It was only 1/4" thick so that didn't help either. I would guess 3/4" or 1" would do the same thing, but would think it would take much longer to show up on thicker material. Keeping paint on it would slow the UV process even more.
I too was told the tale of Medex by suppliers. I went through truck loads of that stuff before I realized some of the signs went from 1/2" thick to 1" thick in a matter of a few years.
Much the same happened with the vinyl laminated Plywood with vinyl edge cap. Used for vinyl lettering & digital prints, not 3d CNC, but a headache none the less. Marketed as totally weatherproof. That is until the silicone sealer in the edge cap channel failed so the edge cap became a trough to wick water into the plywood edge. Sign would look great for years, but if you touched it, plywood dust would fall out the bottom.

[GeneMpls]

I think that Joe will corroborate that most 1/4" PVC is not rated for outdoors, which the thicker material is.

[zeykr]

Good looking fix - can't tell it happened. One of the local park systems always ask for 2 of any sign they order, one to hang and one for backup.

[pro70z28]

I think that Joe will corroborate that most 1/4" PVC is not rated for outdoors, which the thicker material is.

That's true, but the same UV issues apply, just takes longer as I said. I'm guessing my experiment with Sentra was about 25 years ago. I don't if there's been formula changes since then.

[joe]

For years I've been cutting white letters from .75 PVC and not painting them. The only change has been a very slight buff coloring. No chalking. Like Gene says, .25 isn't rated exterior.
Today, on the first surfaces, that are to be painted, I've been sanding with P100 to insure a tight bond. My oldest exterior PVC panel is six years and holding tight. You know, everything has a life expectancy. Wondering if it will out-last me.

I'm feeling tough so I'll let you know if there are any cracks!

[pro70z28]

This is a little off the subject of this thread, but when I here of old surviving signs I think about the vinyl lettering I did on a 50's style diner on Rt 66 not far from us. They have a 2 to 3 ft. facade around a parking canopy that's made of powder coated aluminum. I lettered the face with black & teal 6 year vinyl. That was 20+ years ago and it's still there. It's got a few weather cracks, but it's not peeling at all. The only thing I can figure is the aluminum is dissipating the heat keeping the vinyl somewhat cooler, even though there's nothing around there to block the sun.

[joe]

Gary,

Thumbs up on giving a plus for vinyl. That material has made significant improvements. The latest are the ones used in wraps my outlast us all. I hope so but vinyl's come in several grades with different suggested life expectancy. In general it's a great product. I use it often.

http://www.talkshopbot.com/forum/attachment.php?attachmentid=31597&stc=1