What material is recommended for indoor 3d sign.

[FixitMike]

I want to carve this 3d image from 1" x 22" x 22" material. MDF seems like it would be a bit messy, I don't have a vacuum head. HDU would probably be best, but it is pretty expensive. Other recommendations (with links to source) would be appreciated. This will be my first try with a large 3D carving. I'm planning on trying a 1/3 size first. Any other recommendations are appreciated.

[Leo]

Mike,

I have tried laminating 2x4's, but they warped and cracked - badly. They were jointed, milled planed and glued - side to side to make a panel 1-1/2 thick.

I will try is again but face to face to make a panel 3-1/2 thick.

HDU - yes expensive but by far the best.

MDF - yes messy but a really good choice. Also, it will require some serious smoothing. If completely painting I would recommend some THICK primer and to put 2-3 coats. Your sanding of the primer coats will yield really nice finishes.

A laminate of Maple, of Cherry --- or Poplar is some OK stuff to use, but distortion should be expected.

Sheets of PVC would be a decent choice - AZEK - I have seen it at Home Depot. Still a bit pricy. Still will need some serious "?sanding?". Yech - sanding PVC.

If I were going to do it, and it was painted, and I wanted to be conservative on money - it would be MDF.
If I didn't need to worry about cost it would be HDU

[redwood]

I have no issues laminating dried redwood 1/1/2" thick. It does help that I have a festool domino, for a little more strength and stability. This sign is 22" in diam.

[martin54]

What about insulating foam ? There have been a few posts about using that instead of HDU, there have been threads on the forum about people buying blue & pink foam from the Big Box Stores & getting good results.

highpockets posted fairly recently about a job he had done using it & the finish looked to be pretty good.

Not something I have tried personally so no practical experience to speak about, one of those things I have read others doing & keep meaning to try

[Oldmanofgf]

Mike
I been having good luck with glued up lodgepole pine panels from Lowes. They sell them in full 1” thickness 24x48 or 24x24
They are wrapped in plastic and carve good. I haven’t had any warping so far but I live in a dryer part of the world than you.
The panels from Home Depot are no good as they come unglued The Lowes panels come from Montana or Canada the cost is not to bad. I wouldn’t use them for outdoors projects. Sometime I have to hunt different Lowes to find 1” panel they have more 3/4” ones Just make sure they are Lodgepole pine not white or yellow it seems to be more stable .
Glenn

[Xxray]

I use corian for alot of stuff like that, would be pretty heavy that size and not 1" thick.
Second to none for holding detail though ,,, Foam can be nice, I tend to shy away because it is so fragile.

[Leo]

I will agree with the insulation foam. I have used it with great success. The caveat is that you NEED SHARP cutters otherwise you will get fuzzies that you will not get rid of easily.

[mikeacg]

The foam is messy to work with but cuts fast! Any fuzzies are easily sanded or rubbed away. It also holds very good detail. Here's a sign I just did for a friend's family hunting camp (roughly 18" x 36" x 2"). I usually put a piece of doublestick carpet tape in the middle to keep it from bowing in the middle as you cut.

Primed with a good white exterior paint.