wooden & stainless sign design

[Josh Richard]

My students and I am preparing to make a series of wooden sign. We will be making three sets of 12 signs. Each set will be a fitness trail. Kids will go to a sign and do an activity listed on a stainless steel plate.

The wood will be pressure treated and anchored into the ground. There will be a stainless steel part on a wood plate. The stainless will be cermarked and laser engraved with an activity.

The "roof" part will be cut with a router table into pressure treated lumber.

Here are my questions. Does anyone have experience with cermarked stainless in an outdoor setting, will it last and be readable in a few years?

Will the pressure treated wood accept an 1/8" deep router bit cut design and last as long as the cermarked stainless?

Thanks for the help. High school students have designed and will build these in December for the elementary schools in my district and I want them to be successful!

[Joe Pelonio]

if you cut a hunk of the end of a pressure treated 4x4, you will see that the
chemical only penetrates part way in. That does work fine, keeping moisture from getting to the untreated center. As long as the router doesn't go beyond the point that the chemical reached, that part is OK. Still, depending on the climate it is not likely to last as long as stainless with Cermark as long as the Cermark is done properly. Cermark doesn't work as well on brushed (textured) stainless, and will not work if the stainless has a protective clearcoat, it needs bare metal.

[Scott Shepherd]

Only issue I can foresee is the "roof" piece cupping over time. Other than that possibility, I think you're fine. Cermark should last well.

Just pay close attention to what you engrave in the wood and make sure no clever kid with a pocket knife can change the message to something filthy by making a few cuts. My rule of thumb for outside signs like this is that if it's possible for someone to do something to it, they will, so thinking ahead as if you were a bored kid with a pocket knife now can save you a lot of embarrassment later

Looks good though! Good luck with your project. If you think about it, maybe post some of the finish sign photos when you complete them.

[Gary Hair]

Cermark doesn't work as well on brushed (textured) stainless

I'm curious what problems you have had with brushed stainless? I have lasered a lot of stainless, probably 50/50 grained (brushed) and factory finish, no problem with either.

Gary

[AL Ursich]

For the roof I recommend using Corian and color filling CNC V text or logo with colored Corian Glue then sanding flush.

OR.... Make another Stainless piece for the roof and put something on it....

The Drying out of the deck boards is my concern....

AL

[Josh Richard]

Thanks for all the advice. I do like the idea of the Corian but have never used it. Do you need specialized glues? Also, can the Corian be laser engraved and filled with color?

[AL Ursich]

I am thinking the answer is YES... I have not tried it with a laser... I CNC it... They make color match glue that has been known to be used to color fill V carved text then sanded flush. The contrasting color and flush text is easy to see and the water won't sit in the text and collect dust.

There are a few posts on the Laser Thread about Corian and it's many uses...

AL

[Josh Richard]

New question.

The powers that be do not like the rotary engraved "roof" section. If we burn a design into pressure treated wood with a laser, will the darker area stay visibly dark over the years?

[Mike Null]

It will turn silver gray in short order. I doubt that you can get sufficient depth with the laser to make a lasting mark.

Your original plan of routing was good and durable. If you want contrast use a colorfill on the routed area.

The stainless steel should be fine.