Sign Material help

[jeff_rowley]

Hi, I'm trying to put together a 3D decorative sign as a Christmas present. It would hopefully end up in my sister's kitchen. It will measure 2'x4' and the relief is currently a total of .75" deep. Part of it will be painted with chalkboard paint so it can be written on, the rest will have kind of a painted 'bistro' look (wine, grapes, etc.)

Here's the question, what should I cut it out of? I've used MDF before and it machines fairly well, but left A LOT of fuzzy cleanup and sanding (my wife the finisher/painter is trying to avoid). She suggested using actual lumber, but I'm concerned that in gluing up a panel, if only .75" thick, that by the time I cut out the relief there won't be much left holding the panel together (maybe .25"). Going thicker would make the thing probably too heavy for a kitchen ornament, and seems like a waste of a lot of wood to be milled away (not to mention painting good lumber).

How does 3D work in plywood end up? Baltic Birch typically machines cleanly, I'm just not sure what happens when you start going through plys with a 3D relief.

Any hints or suggestions would be greatly appreciated.

[beacon14]

what about using 1/4" plywood or MDF for the painted area and as a backer for thicker layers of MDF/wood/foam/PVC/whatever you decide to use for the 3D reliefs?

[gene_marshall]

I would use 1.5" sign foam and leave .75 solid behind the releif.

[jeff_rowley]

Would you coat it then and then paint on the coating? What would be an appropriate coating, and is it something that can usually be obtained locally? Sorry, I don't have any experience working with these materials.

[gene_marshall]

Yes,
We prefer "sign prime" or "Jay Cook's" sign primers.
Then you can top coat with just about anything.

You will find that with sign foam, you will carve it VERY clean.( your wife will be happy). I prefer the #18 density for most work.
Also "one shot" paints are excellent for the finish.

We get these products from either harbor sales or vinle sign supplies.
Both have websites.
Both good sources for sign makers.
Although I have not used chalkboard paint I assume that these primers will be OK underneath.
And If I am wrong... someone will post and tell me so shortly.
BTW, plenty of examples on our site.
Gene

[jeff_rowley]

Gene,
Thanks for the feedback. Holy cow, that sign foam gets expensive fast. The whole point of making our own Christmas presents was the 'myth' of saving some money. I have some $80+ maple wood trucks I am working on for my nephews that are rapidly dispelling that myth.

I was reading some other posts that were talking about using the pink 'Foamular' foam from HD and then coating it with a sealer/primer like 'Zinzer'. I cut a scale model of Mt. St. Helens out of the pink stuff for a daughter's science project, just didn't know how to try and coat it. I'm tempted to give this a try.

Hope everyone had a good Thanksgiving!
Jeff

[jhicks]

I have had good luck with the folks at sign Foam, Everwood, and other foam manufacturers / distributors getting samples. Over time I've received mostly 1 ft sq pieces 1" thick and used them for pilots and samples. If you speak with the folks and explain thet you are evaluating the materials for cutting properties, density, and overall consistency they generally can send a few samples. I wouldn't want to rely on this approach for any critical jobs but where you have some time and need smaller pieces, its a viable option.

[joe]

Jeff,

My two cents,

I'd use Trupan. It comes in 4'X8' sheets, .75 depth. If you need extra depth, you could glue a couple sheets with carpenters glue..

We top coat this material with a couple coats of shellac and route away. Shellac dries quickly and stiffens up the surface. It costs about 25 buck a sheet and carves like butter. It can be fuzzy but precoating it will help. A good scrubbing, with a kitchen scrub brush makes short work of removing any stray particles..

In my opinion there is no need to go to HDU. It's an expensive exterior product. Insulation foam isn't going to give you the detail you need. Odd as it may seem, you don't really have lots of substrate options that are cost affective. If we were to go to wood, it would be mahagony or cherry.

The most important part of this project is the design. The best materials, and techniques are supported by good design.

J.
www.normansignco.com (http://www.normansignco.com)

[bill.young]

Hey Jeff,

I haven't found it in any stores yet but Rustoleum is coming out with a water-based spray paint name Aqua (http://www.rustoleum.com/product.asp?frm_product_id=539&SBL=1) that specifically says it can be used with styrofoam. It includes a grey primer which might let you overcoat with other solvent-based finishes.

Bill

[Mayo]

Krylon H2o Latex spray paint works on insulation foam. Do not confuse this with the regular Krylon spray paint which WILL melt the foam.