Wood Suggestion - Large(ish) Exterior Laser-Etched Sign

[Mikah Barnett]

Have a client that wants a sign roughly 3' square for the exterior of their East-coast beach house. They do not want cedar (which we can't seem to find in that size anyway). Not having worked with much in the way of flat panel wood, what do you folks suggest for good lasering properties and good exterior durability?

[Ross Moshinsky]

http://www.sustland.umn.edu/implement/selecting_wood.html

Most likely you're going to have to make your own panel unless you want to pay a real premium for a solid slab. A local wood worker, mill or cabinet shop can help you with that. Without seeing the design concept, my gut says this is a job for a CNC router rather than a laser engraver.

[Mike Null]

I don't think I'd be using laser engraved wood. A better choice would be Corian.

[Joe Pelonio]

I do sandblasted wood signs, many bigger than that, and used Redwood until it became so expensive, then switched to clear cedar which is local. I always have to buy 2x6 stock, rip off the rounded edges, glue up, then cut to size and sand. I suspect that you will have to use whatever is available in your area in clear wood and glue it up too. For laser, in order to get the depth you want for visibility in that size, I would go with something softer like pine, hemlock or spruce. If you go with a router you could use any clear hardwood but that's hard to find in the thickness you need to hold up in that size without warping/cracking.

[Keith Outten]

Dupont Corian is an excellent choice for exterior signs. If you decide to laser engrave Corian for a beach sign make sure you engrave it at least 1/32" deep so you can refurbish the sign when it is damaged by the weather. A rattle can of paint, some tape and an ROS sander is all you need to paint the sign again and again over the years.

For beach properties King Color Core is the best choice but it has to be CNC routed. The reason I prefer Color Core in areas where storms are likely to sandblast a sign with beach sand is because the colors are permanent, there is no paint involved. Color Core is also near impervious to vandalism as paint and permanent makers won't stick to this material. Color Core is also an excellent material for boat signs and instrument panels because the salt water will not degrade the plastic.

[Matt McCoy]

Have a client that wants a sign roughly 3' square for the exterior of their East-coast beach house. They do not want cedar (which we can't seem to find in that size anyway). Not having worked with much in the way of flat panel wood, what do you folks suggest for good lasering properties and good exterior durability?

You might look into cypress which has a nice cathedral grain and is suitable for outdoor applications. It's a hardwood that laser engraves well and has a nice dark contrast. You will have to glue stock together to attain the size you need.

[Mikah Barnett]

Thanks for the thoughts, guys. Corian looks nice but is a no-go as client wants wood. Cypress is probably a good option - will do some more research into getting our hands on some of that.

[Paul Phillips]

If you have to use wood how will you finish it? if your'e painting it then something like cypress might work ok but for exterior use cedar would be best as it stands up to the elements better, similar to redwood it has natural resins that keep it from rotting, there are a few places that sell custom sized blanks.
http://www.allwoodsignblanks.com/index.html

[John Bion]

I hope I am not hijacking the thread......what would generally be recommended for treating outdoor wood signs when left unpainted?
Thanks and regards, John

[Joe Pelonio]

I hope I am not hijacking the thread......what would generally be recommended for treating outdoor wood signs when left unpainted?
Thanks and regards, John
I like to use Tung Oil.

[Mike Null]

I would use spar varnish.

[Mikah Barnett]

I would use spar varnish.

Spar Varnish is what we have here and what we're planning to use.

Client specifically does not want cedar - that was our original suggestion. I do not think at this point we're going to paint the sign, but we don't have a definitive answer there yet either. Also contacted a local cabinet-maker to see if he could make us up a tongue-and-groove Cypress blank, still waiting on pricing for that.

[David Somers]

Mikah,

A shame about their not wanting Cedar. I have some Cedar outdoor chairs I made 20 years ago that are still going strong. No finish or coating on them whatsoever. And l outdoors all the time, including 12 years in Hawaii, the rest in the Pacific Northwest.

Have you thought of Teak? Expensive, but another wood that holds up well to weather. If you want to apply a hard shell coat to it like a varnish you will likely need to remove the surface layer of oil and silica's with something like Oxalic Acid (the main ingredient in Teak Cleaners) and then allow it to dry thoroughly. i would use Oxalic by itself. Teak cleaners add other conditioners to the mix that are probably best not put on the wood before something other than an oil is applied. Might interfere with a varnish or other shell finish.

In terms of finish, consider the sign's surface. If you use a shell like finish like Spar Varnish when the varnish needs to be removed and reapplied is that going to be very difficult to do because of high relief in the sign? (lots of nooks and crannies in other words) Spar varnish can last for ages if it has many coats applied, and each year a coat or two is abraded away and more coats applied over it. That is how it is made to last on a boat without constantly stripping it. Boats will often have 9 to 11 coats of a Spar Varnish applied. And each year a coat or two will be abraded away (sanding) and more coats applied. Once you have cracks in it that go down to the wood you are forced to start removing the finish entirely. It is an excellent finish though. Don't get me wrong. I use it in a marine environment here in Seattle. But it does take upkeep to prevent excessive maintenance work on it, and most are not willing to do that.

Oil finishes are easily reapplied by the owner with little fuss. If that will provide the look on the sign they want of course.

And woods like Teak and Cedar will go silver if allowed to age without a finish. They hold up extremely well like that. Again, those chairs I made 20 years ago have silvered and have lasted 20 years without problem. They have no finish on them at all.

In terms of varnishes, the two part varnishes tend to last longer than 1 part varnishes by a wide margin. Nautithane and Bristol Finish are two examples that do well in southern marine environments. Lasting a number of years before you have to do any sort of maintenance coats.

Hope this helps a little.

Dave

[Joe Pelonio]

If you use teak, it will take a lot more time to engrave, it's a hard wood. I also avoid varnish because it weathers and peels off, oil can be re-applied when needed with no additional work.

[Mikah Barnett]

Thanks for all the help, guys. Does anyone have a picture of a cedar laser engraving that has aged and silvered? Does the engraving contrast stay consistent as the color fades? The maintenance requirements of non-cedar seem to have them considering cedar as an option and we're still pushing that hard as it makes life simpler by far. We have plenty of pictures of "fresh" cedar engraving, but I can't seem to find one of something that's been laser engraved then weathered outside.

[Joe Pelonio]

Mine were mostly sandblasted but it's about the same exce3pt for the depth and grainy background. The weathered look is gray, so if the customer doesn't want it finished I use a lettering color that will show up after time has weathered it. Probably the most popular is forest green, second white, which also shows up well in the dark by headlights for home address or name signs. Third is gold, the metallic gold one-shot, or in some cases gold leaf.

[David Somers]

Mika,

I don't have any engravings. But I do have the cedar chairs that have silvered. Happy to take a snapshot of those if it will help. As I said, they are 20 years old and have never been treated or sanded or even cleaned with oxalic acid. Simply stayed out in the weather either in the open or under a porch roof. Probably 25% of the time under roof. The rest in the open. All seasons.

Let me know. I am home Sunday and can take a shot and post it if you like.

dave

[Mikah Barnett]

Thanks guys! I've got some pictures of weathered cedar, but I can't seem to find a good picture of a weathered, laser-engraved cedar. We could add paint if we have to, but maintenance will be easier if we can just count on a good, dark, deep etch to keep its contrast as the cedar ages. I will keep looking!