Sign For Outside Material?

[kmmcrafts]

I knew sooner or later I'd get a request to make a sign for outside use. I actually have had request but kindly turned them away because I know that outside signs don't typically hold their fresh wood look for all that long.

So this brings me to the questions that have been asked before probably many times.. what material is best for a outside use. I've read to use deck seal finish for longevity but does anyone know how it reacts to acrylic paints? I may be painting the carved text for contrast and will want to top coat the whole sign. They don't really want to use a light colored wood and prefer something along the colors of Cherry however I'm not certain Cherry is something that would hold up to the elements. They want to mount this on a tree leading up to their cabin so it's not going to be sheltered much at all, LOL

So, those wood and finishing pros, what wood should be used and what finishing sealers for the most life out of this sign? Also any tips or suggestions that might help. 

[Norm Fengstad]

I cut our welcome sign from a sliced ACQ treated fence board. Backer also out of fence board was painted with a black acryllic then sign coated with Thompson water seal; had no effect on the acryllic paint . Sign gets completely covered over in snow last 3 winters . Unfortunately this year the sign couldn;t withstand pressures of the snowplow so will have to be replaced!

[kmmcrafts]

I also should note that they want the sign to be approximately 24 x 15 inches so I'm likely going to need to do a glue up and or choose a plywood. Assume marine ply if I go that route but I'm not sure how well it would carve on the CNC and since this is a scroll saw site, doubt anyone here knows that either, LOL. I'm thinking I'd rather go with solid wood anyway. One issue will be gluing up a 15" wide board since my planner is only 13" wide so all boards will need to be the same thickness when the gluing happens and any uneven parts if any will need to be hand sanded flat. Or I can run a surfacing bit in the CNC..

[BadBob]

White Oak, they built ships from it.
Three of the most popular lumber choices for outdoor furniture include cypress, western red cedar, and redwood. Hardwoods such as ipe and teak are also rot-resistant and durable. Other options include acacia, black locust, cedar, and cypress.

Ipe is dark in color and used for expensive decks and flooring. Kind of chocolate brown.

The best protection is exterior paint and spar varnish. If you finish the wood, you will need to refinish it occasionally.

[flarud]

I read your post, then went to Youtube after I finished up here in the Village.  The first thing I saw was this.

 

[Millwab]

Kevin, what about using Trex (or similar) decking?  It is practically indestructible as far as weather goes and I believe you can get it in different colors. 

[John M]

Western Red Cedar holds up to the weather very well and is very easy to work with.

[Brokentone]

I have cut some intersecting word name signs from trex, one has been outside since 2015 and looks as good as new. I don’t think it would be good to cut on cnc as it requires a very slow blade speed. If I cut at a fast speed the blade welds to the material plus the cut welds back.

 I have not yet tried to glue up to make a board wider than 5 1/2”. 
 

Bob

[Dave Monk]

9 hours ago, Brokentone said:

I have cut some intersecting word name signs from trex, one has been outside since 2015 and looks as good as new. I don’t think it would be good to cut on cnc as it requires a very slow blade speed. If I cut at a fast speed the blade welds to the material plus the cut welds back.

 I have not yet tried to glue up to make a board wider than 5 1/2”. 
 

Bob

I have also used Trex. Facia boards are available at some Lowe's stores up to 11" wide.  It is sure hard on blades but there is no need for finish. I also painted a piece black and used it for the backer. 

[Millwab]

13 hours ago, Brokentone said:

I don’t think it would be good to cut on cnc as it requires a very slow blade speed. If I cut at a fast speed the blade welds to the material plus the cut welds back.

 I have not yet tried to glue up to make a board wider than 5 1/2”. 
 

Bob

I’m not sure cutting with a scrollsaw and routing would have the same effect.  When cutting you are essentially separating the piece into two parts. With routing you are just carving out a piece. Haven’t done either with this material so I can’t speak from experience.  I have glued up pieces of it to make a wider panel and that worked well. I used gorilla glue (urethane?) and just had to clean up the foam it created as it cured. That was many years ago and there may be better adhesives to use now.

[kmmcrafts]

The customer sure likes the look of Cherry.. not sure how well Cherry will hold up out in the elements? Anyone know or have any experience with Cherry being outside? 

I'm wondering now what the best option for a finish might be to help preserve the wood. Whatever type of final finish I go with will need to be compatible with whatever paint I use for painting the carved out areas. I typically use either acrylic craft paints or sometimes if it's all going to be one color I'll just use whatever spray paints I have on hand. 

I've heard exterior house paint is great on signs and I've done it several years ago on a scrolled sign I had that I used a backer board on for the contrast.. just buy the base paint without any pigment, the paint shops look at you kinda weird when you don't want any mix in it,  so I don't know how the house paint would do with the acrylics... Also thought about just using some automotive K2 clear since I have some left from a paint job I did a while back.. again I'm doubtful the K2 clear will do well on the acrylic paints though, LOL

Anyway, if anyone has suggestion about using Cherry or finishing suggestions I'm all ears, LOL.. I know I can make it look good for short term, just like to give them something more long term. Their intentions are to screw it to a tree out on the front yard / driveway so it'll be out in the sun / shade? / rain/ and snow... I told them I wasn't sure how long it'd last being out there like that. 

[Bill WIlson]

From the Hardwood Database,  Black Cherry | The Wood Database (Hardwood) (wood-database.com)

Rot Resistance: Heartwood is rated as being very durable and resistant to decay, though not typically used in exterior applications.

[kmmcrafts]

Thank you Bill ! That helps ease my mind. I'm always wanting to make the best product possible and meet the customer needs / wants as best I can. 

 

I went to my local lumber supplier this morning and talked with a couple of the employees that run a side hustle making signs with their CNC's.. They told me the best finish / sealer options was either Spar varnish ( which would need sanded and recoated yearly) or they have a epoxy finish that really works and holds up very well and no need re-coat it basically for a very long time.. Not the cheapest stuff but I personally know this customer and know they'd rather pay more up front than to mess with sanding and sealing every year.