Need suggestions for how to build a sign...

[Ernest T. Bass]

I suppose this could go in the General forum, but it's not exactly construction.. I just need a little advice from you pro woodworkers out there. I'm going to be building a largish exterior sign, about 5'x3'. Here's a pic of what it will hopefully look something like:



I'm going to be routing the lettering... I'm trying to figure out the best way to make the sign blank, or big-slab-of-wood. The routing will be fairly deep, up to a half-inch and the sign is double-sided. I had been thinking of sandwiching three layers of 1'' t&g with glue, alternating the grain directions. I also thought I might run threaded rod right through the core of the sign, bolting through the posts on either side.. My biggest concern using solid wood is shrinking/swelling. If t&g paneling is glued together with alternating grain directions, will it eventually bust apart as there is no provision for movement?

What about using a 3/4'' plywood fastened to an inner frame of boards instead? Ideally, I think it would look nicer if the wood grain were exposed (clear coated or light stain). Could birch plywood be urethaned and left exposed to the elements?

Thanks for any advice!
-Andrew

[desimulacra]

Lot of good info on shopbottools.com they have a signmakers thread

[MountainDon]

Moved... you never know what someone may want to build...

[rwanders]

  Would some of the engineered wood products work-----ie; layered LVLs or perhaps use a glulam? They seem to be pretty stable, especially if given some good coats of oil-based polyurethane.

[Ernest T. Bass]

It's an interesting thought... I'm not sure if an LVL would be the prettiest thing, but perhaps paint grade. I would think it'd router okay... Nowadays most carved signs are made of high density urethane, but laminated 4x6 redwood timbers used to be more the standard--perhaps laminating engineered lumber would be a similar process but more stable.

[glenn kangiser]

Engineered lumber is not pretty if it gets moisture.  It swells and doesn't go back.

[Ernest T. Bass]

I keep reading about MDO for signs, but can that stuff get routed? Doesn't seem like you'd want to cut through the veneer.

Any idea if the cris-crossed and glued t&g would have any problems?

[muldoon]

I was hoping there would be more answers to this question as I was hoping to learning something here as well.  If I was to tackle this project, I would follow the basic principles of a panel door.  The outside frame is glued and the inside panels sit inside a rabbit- free to expand as needed do to moisture.  Those inside panels would be 3 to 4 tongue and groove panels freely connected. 

something not unlike the principles outlined here. 
http://www.rockler.com/articles/display_article.cfm?story_id=103&cookietest=1

For exterior signage, I would try to work with cedar, teak or cypress, perhaps ipe if the budget allowed. 

[rwanders]

How about sections of glulam?----I believe it would weather well if polyurethaned and also looks good if clear finished with routed letters enameled in a solid color. Swelling should not be a problem if maintained periodically.

[JRR]

I've never done this task ... but have given it a bit of thought, as I might do a street address placard to put up against brick home.

My thought was to build up a pattern using purchased letters and numerals, mounted to a heavily grained wooden "back surface".  Using modeling clay, or plumbers caulk, to apply some radius to what would otherwise be sharp corners where the characters meet the background.  Put fancy/plain edgeing around the whole thing ... and then pour a thin, but well reinforced with wire, ... concrete/plaster/stucco fill that becomes the final (long-lasting/non-shrinking/etc) sign.  All the sign info would be "in relief" ... just like routing.

A few days cure ... strip from the pattern ... and then paint.

[Ernest T. Bass]

Some interesting ideas guys... Thanks! Muldoon, The sign needs to be at least 2'' thick in order to router both sides. Are you talking about attaching a few layers of 1'' t&g together with the grain running the same way? I'm wondering if I should just do that--or maybe just frame a square and glue the t&g to both sides, but not together (no glue in the grooves). Maybe that way each board would have enough freedom of movement without affecting the sign as a whole. I wouldn't imagine the wood will do too much swelling once it's been marinated in urethane either, but what do I know...

Also, does it really matter what type of wood I use if it's going to be heavily sealed? Seems cedar is always recommended more than spruce or pine, but are the decay-resistant properties of cedar really going to have an effect after it's been coated in plastic?

[Redoverfarm]

Andrew why not use composite decking boards.  No shrinkage, no splitting, slight color fading, will not rot and it can be milled.

[Ernest T. Bass]

Never heard of that before... Those boards can be routered and painted? Perhaps two layers on opposing diagonals... Do they take glue? Perhaps I ought to do a little research on those things...