Hi: I am making three exterior signs of different sizes (two of them free hanging) and I am concerned about warping.
The largest one will be about 44"w X 22"h and will be supported by 4"x 4" posts. I think 1/2" MDO should be fine for it because the support the posts will give the sign board.
The others will be smaller: 22"w X 12"h and 36"w x 16"h and they will be hung from sign brackets will no other support. Should I expect warping with 1/2" thick MDO at those sizes and therefore use 3/4" instead?.
I guess I am not real clear on when it is best to use 3/4".
Thanks for any comments.
Pat Sweeney Highline Signs Terre Haute, IN
Posted by John Arnott (Member # 215) on :
If your worried......use 3/4" .....simple. If it does warp.....shouldn't matter. There awful small to worry about.
Posted by Checkers (Member # 63) on :
Hiya Patrick, It would really depend on the MDO and the number of plys or layers. However, I probably would just follow John's advice and use 3/4" unless you keep both or the other in stock.
Havin' fun,
Checkers
Posted by W. R. Pickett (Member # 3842) on :
...For hanging signs, I use the 1/3" (double side) because it weighs less.
Posted by Joey Madden (Member # 1192) on :
I have 1/2 inch MDO outside outside year round hanging signs, some laying on the ground, some painted, some not, some standing against my shop all w/o warp age Posted by Michael Boone (Member # 308) on :
I would use Di Bond or Omega bond
Posted by Bob Rochon (Member # 30) on :
On the hanging signs, you'd be fine with 1/2" MDO, dibond or omega bond in my opinion would be too light for hanging, but an excellent substrate non the less.
[ July 23, 2009, 02:39 PM: Message edited by: Bob Rochon ]
Posted by Michael Boone (Member # 308) on :
If its too light Rochon....paint it darker!!!!
Posted by Ray Rheaume (Member # 3794) on :
My general rule of thumb...
If it's two sided...3/4 MDO. Less chance it warps either hanging or between posts.
Single sided signs hanging, posted or flush on a surface...1/2' is fine if you coat the back with latex paint or water sealant.
my 2 cents... Rapid
Posted by Cam Bortz (Member # 55) on :
The difference in cost between half-inch and 3/4 MDO is too small to sweat over, IMHO. Better to concern yourself with getting GOOD QUALITY MDO, from a reputable supplier. That means not buying the cheap 5-ply crap made for concrete forms. Good 7-ply 3/4" MDO is made by Olympic; don't bother with the pre-primed; you can put a better coat of primer on it yourself.
One good rule of thumb - when buying MDO, look across the faces from an angle in good lighting. If it has ripples or you can see the faint outlines of those football-shaped bungs, don't buy it!
Posted by Patrick Sweeney (Member # 4123) on :
I have ended up learning more than just what I asked about: thanks.
I didn't know to look for different construction and plys. I don't use a lot of it so when I need some I have just been grabbing a piece from Menards. I inspect it for defects of course but I thought everything else was equal.
This site taught me to seal the edges of MDO with Titebond II glue and I have a couple of MDO signs that have been up almost 7 years and are still sealed perfectly.
Titebond and Porter Paints have worked really well for me but all along I may have been dressing up a pig by not watching out for the quality of the board itself.
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